After making the mistake of purchasing and then suffering with the Powerbeats product, I found a deal on the 4iiii left side crank (Ultegra) and I couldn't be happier. Like Wahoo, they seem to make a product that simply works! For most riders of my ability (real and imagined) the minor differences between perfection (or your standard) is of little value but reliability and consistency rules the day. As always, thank you for producing both entertaining and informative videos.
Iv had a 4iiii for almost a year. The non drive side. Been great, I recommend it and it's all u need. It has a scale factor you can program to compensate for left right leg strength imbalance.
I bought one recently for about £220 to put me on until my iQ2 dual side arrives (if ever). Absolute bargain. Very happy with it and reads very close to my Wahoo Kickr.
I've just picked up the 4iiii ultegra for £285 delivered. Works a treat and pairs perfectly to my garmin. It's great having all the data while out on the road.
just bought a refurbished 105 and i'm very happy with it. the 3 second power does take some time to get used to, because the numbers aren't given immediately
Been using this one for a while, more than happy with it. It's not ridiculously over generous with the power readings, and certainly doesn't steal as much power as Strava!
Just bought the 4iiii Precision 3 Power Meter when they had a 15% off which is the regular price on the Precision 2 , really good price and all I needed for my bike computer to work with, thanks for the review, hopefully you can do the precision 3 review soon
Shane, This is a very timely video. I owned an identical left leg 4iiii power meter which was amazingly accurate and tracked my NEO perfectly... Until it just stopped measuring torque. Cadence? no problem at all, but just Zero watts always. It could not be fixed and was out of 12 month warranty :( Problem is, my friends 4iiii also just stopped measuring torque too. Cadence was fine again. Both of our 4iiii's failed between 18-24 months of use. Do a search on the web and you will see our story repeated many, many, many times. I am convinced there is something inherently wrong with the 4iiii strain gauge or bonding cement. While initially ok, consistently fails within 2 years. I don't want to throw shade on what is an extremely accurate PM product but I warn potential buyers to research the long term ownership information that is out there.
@@davidmoreno790 Most likely buyers just have to buy a new one. I don't know of any companies which will simply send buyers a new one after the warranty expired. Nothing lasts forever, and they have "planned obsolescence" in mind when they manufactured, priced and determined the warranty period.
My 4i Ultegra crank power meter over reads by 20 per cent, looks good but not true. Shane did you say that there is a correction factor in the App?Thanks Chris
Great review and thanks for the great data, I just bought a 105 left PM and I love it it has change the way that I train and pretty reliable, ill be checking out the spikes that you mention when I do my first FTP test, good review and awesome work please do keep up!
I have 105 groupset. Thinking whether to buy the ultegra power meter (in case of future upgrade) or the 105 power meter which is cheaper. Wondering if others used the 105 power meter on ultegra because it is cheaper
Got a 4iiii on my indoor bike. Power data is very close to my Assioma Duo pedals. As mentioned by others the 4iiii company gives great service. Recommended by me if you want a low cost accurate power meter.
Over here in the EU the 105 and Ultegra models are often found for 300 euros or under at various webshops, making this a great option imo. (I have the 105 version for a year now, no issues whatsoever)
Had this for a while and really liked it. I had an issue with the battery cap breaking the tab on the actual PM part, but 4iii repaired it free of charge. Had to get rid of it recently, as I changed my steed to a Gravel bike with a Praxis Alba crankset :( Trying to work out the best way to get power on that bike now.
Hi Shane, is there such thing as a 1.0? Is there a way to tell that the one I am buying is the 2.0 if they don't mention it? Is there a difference between the red battery cover and the white one? Worried about old stock. Thanks.
I would be really interested to know the answer to this question too... seems a little confusing what the differences are between the red and white covers and which version is which? Any ideas Shane?
Bought one of these early summer, and the readings are so super spiky, it actually makes it quite difficult to use, even with 3 second smoothing. I certainly never use it indoors. Kinda wish I'd gone for Stages now...
I was going to buy Stages but then found Emily Fowler TH-cam video of bike mechanic saying they were encountering issue with the pod delaminating from the Stages crank creating inaccurate wattage readings so I bought 4iiii instead
OK I guess I’m not the only one who thought this. My first time riding with this, I tried doing a 20 minute power test but ended up having to constantly accelerate and decelerate. I couldn’t tell whether this was due to my L/R imbalance changing a lot or if it was because of poor reading.
Hi Shane... I have this 4iiii PM on my Ultegra Carbon bike... and the Garmin 530.. and I used it all summer but, I am embarrassed to say I have no clue how to properly benefit from a power meter... Can you maybe do a session on Power Meters for beginners? Including what parameters to set up on the Garmin... for example, I used the instant power reading at first, then I switched to the 3s reading... I have no idea what I'm doing... what all this means. Can you also point me to some good reading material if possible? I'm just 60 year old amateur rider... not a strong rider.... I do ride 80-120km hilly rides 2-3 times a week in the summer, but my average speed ends up around 19-22 km/h.... Had some extra money to blow so I bought myself a power meter... LOL.
I am not a pro; but I like the idea of riding with a power meter like I do in my trainer. This power meter is relatively inexpensive here in the US compared to other pedal ones I’ve seen. Looking at the graph, yeah it is not perfect. In my case though, I think that is good enough. So I may just go for it. Thanks for the review
Great video! I have a 4iiii and I want to check it’s accuracy. The only thing I can compare it with is wahoo trainer. How did you import these data to one chart to compare?
Another great and helpful review Shane! Could I trouble you for a unrelated question. On zwift why can't I see average wattage for segments like I can out in the real world? I am using a bike without a power meter and a wahoo kickr.
@@gplama I have to say I was Very dissapointed when I did the alpe and after the ride (after the descent) I checked the segment to see what my average wattage was going up and I couldn't see it! I felt like I did a good power (for me), it was a sad moment.
Missed the protocol the power figures were being recorded over - ANT+ power rises/drops on a standard channel period, shifted by +/- 1 second are going to be difficult to separate in any meaningful way. If a PM is ahead or behind in those cases ? Meh, probably more indicative of sampling than sensor placement.
@@thisandthatandotherthings Good question. 99% of what I do is over ANT+ indoors and out. If it was any different with Bluetooth I'd be pretty pissed (and have less time in the day as it'd require x2 the testing)
@@gplama I'd doubt there's any significant difference in the values over ANT+ and BTLE. There are places where things do differ though, e.g. sampling rate and timing and processing in the head-unit. Bottleneck is invariably in the head-unit, and without firmware updates to those we'd not be able to get hold of the finer grained data that's actually available from the 'device' (trainer, PM etc) over either protocol. One thing that *might * be interesting is to capture power from over both BTLE (via FTMS or CPP) and ANT+ (FE-C or Bike Power Profile) and combine them - you might get effectively a higher sample rate to look at sprints and such, pain in the arse for general work though.
Hi Shane, considering the ongoing issues with the P3, should I go after a discounted P2, a stages or an assioma Uno? I currently ride with MTB shoes, so the Uno would involve getting new shoes as well, which is why I was tending towards the crank-based ones. Is the Uno so much better it is worth the higher investment? Congrats on the amazing work, really useful for us!
Thank you for the video, I’m trying to decide between this and the stages now that the price of the stages has just been dropped, I’ll be getting the Ultegra 8000 one, just wondered if you had a preference for one product over the other?
Great review, thanks Shane. Have you had a look at the dual-sided version? I assume it suffers from the classic Shimano crank right-side disease. Or have 4iiii applied some witchcraft to it?
The 4iiii is horribly off on my bike. It was ok initially, but now it shows about 30w too little when I compare it to my kickr @200w in erg mode. My other Powermeters (quarq and SRM) are within +/- 1% with the kickr and show no leg imbalance.
Hey Shane. I’m in the market for a smart trainer... Leaning towards the Wahoo Snap... does it matter if it has a power meter or not if I already have the 4iiii on my bike?
4iiii, Stages, Pioneer, InPeak, XCadey... all single sided left meters do the same... assuming they're accurate. My personal preference is the InPeak after they resolved the firmware issues and came up with some really good numbers.
Hi S.Miller, great review as usual. Quick question, which would you recommend between this and the stages gen 3 left only. I started riding in April to lose weight and have done 5,580km and dropped 27kg so far. I now want to improve on my training and maybe gain better average and power so new bike and power meter. What’s your recommendation? Stages or 4iiii. Thanks
First up - That's awesome progress on the weight-loss mate. I've no doubt that has been a ton of sacrifice and even more hard work. Well done. As for the technology - There's really not much between these two. Most companies who make a single side Shimano power crank have it nailed after many years of production. Either will do both ANT+ and Bluetooth too.
Is this still an issue to date or has this now been rectified by 4iiii looking for a dual sided power meter ready to do a charity bike ride from lands end to John o Groats over a 12 day period or should a just get the single sided. Any advice would be appreciated :)
Hey Shane, since the last windows 10 update that was pushed my bluetooth connection went from 100% rock solid to a 3-5 second drop out every 30 minutes or so. I remember Zwift sending an email about it, but haven't heard anything since. Is there any word on changes?
Nothing seen in the update list they publish. It’s something I’d hope they’d get on top of rather than sending ‘don’t upgrade your OS’ emails.... which from a security standpoint isn’t ideal.
Hi Shane, i have recently bought a gen3(single sided), which I am using with a garmin 530. There seems to be an issue with the scaling factor not being applied consistently. One moment it would need to be 0.5, stopping for lunch and restarting it would need a 1 scale. Have you heard of similar issues?
@shane - you said in a reply in this thread roughly a year ago that you didn't really have an opinion either way between the 4iiii and the stages single sided (from my P1 pedals I know I'm not wonky). Is that still the case? 4iiii is sounding like the way to go currently.
One question: I have this 4iiii power meter and the Magene Gravet 2 smart trainer. Which one should I use as a power data source? 4iiii should be a bit more accurate but it's only one side power reading. Thanks.
I have the 4iiii and Elite Drivo using Trainer Road but in my experience their accuracy was about on point with maybe a 2-4 watt difference. If you're talking about controlling erg mode though the smart trainer is gonna give you a much better results. I tried using my 4iiii with power matching turned on and it kept hunting up and down during erg sessions so my final power would be about right but I'd be going up and down by 20+ watts.
@@VirgilOvid yeah it's about trainerroad. I've been using the 4iiii power meter as the power source and set the powermatch to auto to control the erg mode. The result is that the power reading fluctuates a lot in the range of +/-20w. I go on the Strava and see others have fairly smooth power reading on trainerroad and mines is very volatile.
I'm using a Wahoo Bolt to control a Tacx Flux. If I use the 4iiii the power will fluctuate +/-20W for me too. I don't feel any change in my legs, and when riding outside the 4iiii is reporting much smoother numbers. I'm ok with using power from the Flux, but I'm currious about how this work.
I use vector2s with trainer road on a Kickr17....I think ideally you would want to use the 4iii as the source of power as it will be the same source of power on the road as well. That being said I was also experiencing so wild power swings early on with power match in trainer road which made it difficult to use and very frustrating. It turned out in my case that I also had power matching turned on in the wahoo utility app and basically had the kickr and the pedals fighting over control. I am not sure if the magene has the same sort of app or not but perhaps support on trainer road can help sort you out.
I'm looking at getting either a Stages or 4iiii Ultegra left only crank for my TCR Advanced Pro 1 (2019) but the frame clearance looks awfully tight for the 4iiii. I have a Wahoo cadence sensor at the minute that just (& I mean just) fits. The pod looks a lot bigger on the 4iiii than the Stages. Did you have any frame clearance problems with this Shane?
How accurate is the cadence sensor and under what circumstances do you have to apply the zero offset and how long does that take? Any idea if the smoothed out the spikes?
Cadence is pretty much a solved problem across the board.....on averages. Zero before every ride is advisable. No idea on any updates on this. 4iiii haven't been in touch since posting my detailed report on the L/R units mid last year.
Has anyone tried this on a bike with a BBRight bottom bracket (Cervelo R2 in my case)? I’m thinking of getting one but I’m not sure if it will clear the chain stay. The sizing guides on 4iiii website seems to say it will, but just barely
Shane iam so frustrated with my Assiomas....they were so promising but after moving from Virginia to California...they no longer wake up the app just never wakes them up and they never seem to be charging before they would charge from blinking orange to green blinking ....bot anymore...considering ditching for 4iii...plus it takes the folks at Favero to respond...what is the matter with them👿
@@gplama Your our Savior, I threw your name there and told them I found it easier to get help from an influencer than them Favero🤣...they been pretty responsive and apologetic...so GP...apparently one suggestion was to swap the USB charging cable, yep can't make that up and walla it started charging again! Insane but just know that's one of the basic trouble shoots...otherwise freaking taking videos while cranking wheel with them trying to log in deep state style to reset felt like a Nightmare to me🤣
Hi Shane, Thanks for the review. Do you know if the FCR7000 crankarm is compatible with my old FCR563/565. As my trainer is a vortex and wanted a more reliable power reading. Cheers
I do not have a proper headunit for now (planning on getting a wahoo elemnt). I am going with the strava app right now. Can i show the power directly in strava while recording the activity?
Hi Shane, thanks for another great video. In the market for my first power meter and it’s between the Assioma UNO pedals and this 4iiii Ultegra. Which would you recommend? Thanks
Hi Shane I have the stages gen 3 and I see that the numbers are lower than my tacx fortex by 20-30w is there a way like the 4iii to do this adjustment manually through the app? Thanks in advance
@@gplama just to point out this is for the left crank stages only I don't have the duel sided PM is it still the same case where my vortex could be wrong?
I have a 4iiii ultegra and a power2max and the numbers aren’t the same. The 4iiii seems to always be under reading with about 10-15w. Which one could be reading faulty?
Is imperative to adjust the scale factor? I do test the 4iii single sided powermeter in a turbo trainer from tacx and if the tacx give me 200w the 4iii alwais shows 20 or 30w less... and is completely new 🤔
I've been stumped, but for me I cant figure out why left handed power meters dont report accurately for me. I've tried 4 stages and assioma left handed power pedals and against my tacx neo and quarqs left handed always reads low, 40w at 300w range.
@@gplama my tacx neo and 3 quarqs on 3 bikes all match nicely, but I can never get left sided only power to match. It seems like there is something to my pedal dynamic and my l/r balance is typically 47/53 so so at 300w that would mean +18w error vs left only. But 40w is the hard to account part.
Exactly the same thing with me. 4iiii reads higher in z1-2 then z3-4 it reads lower. VO2 max, 320 watts on Neo might read 300 on 4iiii. I've put it down to my right leg being more dominant when the going gets tough!
@@lebowskii98_9 Me too... I bought mine in 2018 (version 1.0?) and up until recently thought that it was fine, but then compared to a Wahoo Kickr, have found it reads high for low power (10-15%) and low for high power (7% out). Right leg more dominant - possibly. Can you get R/L split power analysis on a dual sided to confirm? I reckon I should do this too. Was going to send back, you have me thinking.
If you must pick a single sided pedal power meter would you go for Assioma Uno or Garmin V3s? The price is almost the same for both... I am looking for stability accuracy but mainly consistency and maybe next year want to buy the second pedal but today I do not have budget for dual ..
may i know if this power meter is compatible with all bike computer head units which measures power? especially to LEZYNE MINI. i am planning to buy bought of these units together. And also, will this power meter also be used in ZWIFT for my indoor rides? thanks
Can I use the 4iiii Ultegra FC-R8000 Left Arm Powermeter with a Chainset: Shimano Ultegra FC-6800 Hollowtech II, 50x34T w/BB(BSA), Crank Length: 170mm-47/54cm?
I just bought one and after 1 hour or so of riding it start to read low values. Like 50 watts lower. I compared it with a smart trainer and another power meter just to be sure. Does anyone have see this problem?
@@gplama I bought mine in 2018 (version 1.0?) and up until recently thought that it was fine, but then compared to a Wahoo Kickr, have found it reads high for low power Z1 (10-15%) and low for high power Z4 (7% out). But this may be an imbalance in my legs?
@@AndrewRoberts42 There's a lot to dig into there.... single sided meters vs total power means there's always questions about balance. That's only resolved by having a true L/R meter... and having one of those means you don't need a single sided meter :)
Yesterday I tested 4iiii utegra left crank against the tacx trainer and is giving me less 25-30W than the trainer... The crank is new... I'm very disappointed.
@@gplama thanks for the response. I do the workout at the same time with 4iiii left crank and tacx flux. In the past I do the same using the same trainer but with quarq crankset and the values are the same on both devices. Between 4iiii and the tacx flux is more than 6% less power in the 4iiii... 🙄
@@brunocosta3877 I bought mine in 2018 (version 1.0?) and up until recently thought that it was fine, but then compared to a Wahoo Kickr, have found it reads high for low power Z1 (10-15%) and low for high power Z4 (7% out). But this may be an imbalance in my legs?
i have one on my gravel bike and so does my partner. after 4 months i had to send mine back because i was unable to calibrate it. now my partners is doing the same. :(
@@gplama returned it to the bike shop. we put the OEM crank on while they sent the PM back to 4iiii . about 5 weeks later i got it back all working no problem since.
My 4iiii left side read about 6,4% over my neo 2T installation torque is 👌 and my balance right left power is 49/51 and 51/49 depending of the ride or race i dont have a lot of diff. Its normal or not thanks
You're comparing two different things. Left x2 vs total power. It's impossible to tell what's right or wrong without more data (dual sided cranks also measuring total power) or a set of power pedals with true L/R measurement to compare.
Shane Miller - GPLama Sorry, I misspoke. Last year I had the Garmin Vector 3 and I never had more than 51/49 49/51 between my two legs. This year I have 4iiii dual side powermeter, except that the right side is badly calibrated (shimano crankset) I think it's better just to take the left side but I have about 6.5% compared to the Neo 2T. Am I more accurate with the left side only or do I adjust the right side with scale factor? Thanks
@@jean-philippevenne4369 If the issue could be resolved with a scaling up of one side, that's how they'd be sold and there would be no issues. Entirely your call how to obtain more accurate numbers though.
Hey Shane, what was the worst instance of L/R imbalance you’ve ever encountered? I feel like my L/R imbalance changes depending on how much torque I’m putting down. So at the same power, if I try to spin up, (I think) my left leg drags and the power reading dips. I found it extraordinarily difficult to maintain a steady power up a slightly inconsistent grade during my 20 minute power test. I was around +/-35% from target, I would say. I’m wondering if this is due to my imbalance, the power meter or just my crappy pacing. Thanks!
There's no answer I can give that'll help here. Everyone is different. The solution is not to use a left only power meter (spider based, crank L/R, dual sided power pedals, etc).
Shane, As always your reviews are very informative and entertaining. You are the go to source for me for sure for cycling gear and technology. Maybe this is a dumb question but I believe I have as options, the Praxus + 4iiii for my Roubaix Sport but it appears that the Assioma Duo is not that much more expensive plus you have the advantages of two sided data and being more portable. I believe the duos are rechargeable where the battery for the 4iiii is only rated for 100 or so hours That equates to about 7 weeks of riding for me. If I am not so worried about the slight upcharge, shouldn't i just go with the duo? Thanks in advance if you get to respond. Of course I would be anxious to hear what anyone else with knowledge might want to share or offer.
Yeah, I'm across that. See my report here: gplama.com/2019/06/29/shimano-crankset-power-meters/ This, and Keith's video is about the RIGHT side issues.
After making the mistake of purchasing and then suffering with the Powerbeats product, I found a deal on the 4iiii left side crank (Ultegra) and I couldn't be happier. Like Wahoo, they seem to make a product that simply works! For most riders of my ability (real and imagined) the minor differences between perfection (or your standard) is of little value but reliability and consistency rules the day. As always, thank you for producing both entertaining and informative videos.
I'm 3 years into using one and it has been flawless. :)
Is there any difference between the 105 and Ultegra? Just a different sticker?
@@nicolasmoreau3434 They are interchangeable, but the Ulterga is lighter in weight.
@@adcuz 7
I've got the 4iiii PM on one of my bikes and love it. Great customer service too if you have questions
Iv had a 4iiii for almost a year. The non drive side. Been great, I recommend it and it's all u need. It has a scale factor you can program to compensate for left right leg strength imbalance.
how to check if i have right strength imbalance?
How can you find this value 🤓?
For an absolute amateur such as me, it seems pretty ok. Nice, as I was lucky and got a very good deal on it and has been using it this summer.
Rune Kleven where did you find a deal on it?
I bought one recently for about £220 to put me on until my iQ2 dual side arrives (if ever). Absolute bargain. Very happy with it and reads very close to my Wahoo Kickr.
I've just picked up the 4iiii ultegra for £285 delivered. Works a treat and pairs perfectly to my garmin. It's great having all the data while out on the road.
Mine is coming this week had a 4iiii 105 but my newTCR is Ultegra , my 105 was great 👍🏼
thanks!!! hopefully the piggybank is full in march, ready to hit the roads again with a 4iiiiiiiiiiiii powermeter on the bike
Niiiice!
just bought a refurbished 105 and i'm very happy with it. the 3 second power does take some time to get used to, because the numbers aren't given immediately
Been using this one for a while, more than happy with it. It's not ridiculously over generous with the power readings, and certainly doesn't steal as much power as Strava!
The best bang for bucks. Cheap enough for my commute and work on zwift too
Just bought the 4iiii Precision 3 Power Meter when they had a 15% off which is the regular price on the Precision 2 , really good price and all I needed for my bike computer to work with, thanks for the review, hopefully you can do the precision 3 review soon
Ball is with 4iiii on this one. I'm waiting on a new/updated firmware for the unit they sent over.
Shane, This is a very timely video. I owned an identical left leg 4iiii power meter which was amazingly accurate and tracked my NEO perfectly... Until it just stopped measuring torque. Cadence? no problem at all, but just Zero watts always. It could not be fixed and was out of 12 month warranty :(
Problem is, my friends 4iiii also just stopped measuring torque too. Cadence was fine again. Both of our 4iiii's failed between 18-24 months of use. Do a search on the web and you will see our story repeated many, many, many times. I am convinced there is something inherently wrong with the 4iiii strain gauge or bonding cement. While initially ok, consistently fails within 2 years.
I don't want to throw shade on what is an extremely accurate PM product but I warn potential buyers to research the long term ownership information that is out there.
Cheers for the comment. Always good to get real world user experience as feedback (especially for the companies)
And did the company say something about it? Or were you just abandoned by them after the warranty period?
@@davidmoreno790 Most likely buyers just have to buy a new one. I don't know of any companies which will simply send buyers a new one after the warranty expired. Nothing lasts forever, and they have "planned obsolescence" in mind when they manufactured, priced and determined the warranty period.
My 4i Ultegra crank power meter over reads by 20 per cent, looks good but not true. Shane did you say that there is a correction factor in the App?Thanks Chris
Great review and thanks for the great data, I just bought a 105 left PM and I love it it has change the way that I train and pretty reliable, ill be checking out the spikes that you mention when I do my first FTP test, good review and awesome work please do keep up!
Did you pair it with 105 groupset as well?
@@rommelreyes2209 yes indeed the whole group is 105.
I have 105 groupset. Thinking whether to buy the ultegra power meter (in case of future upgrade) or the 105 power meter which is cheaper. Wondering if others used the 105 power meter on ultegra because it is cheaper
Got the recent duel 4iiii and it’s great.
Got a 4iiii on my indoor bike. Power data is very close to my Assioma Duo pedals. As mentioned by others the 4iiii company gives great service. Recommended by me if you want a low cost accurate power meter.
Over here in the EU the 105 and Ultegra models are often found for 300 euros or under at various webshops, making this a great option imo. (I have the 105 version for a year now, no issues whatsoever)
Thanks for the review. I just bought one. Cant wait to try it out.
Had this for a while and really liked it. I had an issue with the battery cap breaking the tab on the actual PM part, but 4iii repaired it free of charge. Had to get rid of it recently, as I changed my steed to a Gravel bike with a Praxis Alba crankset :(
Trying to work out the best way to get power on that bike now.
i have a Praxis crank and have one of these power meters. just not sure on the particulars of the Praxis i have.
Hi Shane, is there such thing as a 1.0? Is there a way to tell that the one I am buying is the 2.0 if they don't mention it? Is there a difference between the red battery cover and the white one? Worried about old stock. Thanks.
I would be really interested to know the answer to this question too... seems a little confusing what the differences are between the red and white covers and which version is which? Any ideas Shane?
This is working great on my commuter w cap painted stealthy black
Do an Avio power meter review
Bought one of these early summer, and the readings are so super spiky, it actually makes it quite difficult to use, even with 3 second smoothing. I certainly never use it indoors. Kinda wish I'd gone for Stages now...
I was going to buy Stages but then found Emily Fowler TH-cam video of bike mechanic saying they were encountering issue with the pod delaminating from the Stages crank creating inaccurate wattage readings so I bought 4iiii instead
OK I guess I’m not the only one who thought this. My first time riding with this, I tried doing a 20 minute power test but ended up having to constantly accelerate and decelerate. I couldn’t tell whether this was due to my L/R imbalance changing a lot or if it was because of poor reading.
Hi Shane... I have this 4iiii PM on my Ultegra Carbon bike... and the Garmin 530.. and I used it all summer but, I am embarrassed to say I have no clue how to properly benefit from a power meter... Can you maybe do a session on Power Meters for beginners? Including what parameters to set up on the Garmin... for example, I used the instant power reading at first, then I switched to the 3s reading... I have no idea what I'm doing... what all this means. Can you also point me to some good reading material if possible? I'm just 60 year old amateur rider... not a strong rider.... I do ride 80-120km hilly rides 2-3 times a week in the summer, but my average speed ends up around 19-22 km/h.... Had some extra money to blow so I bought myself a power meter... LOL.
That's a great idea. I'll note it down. Thanks!
Can be use with pinion gearbox
Ty🙏
I am not a pro; but I like the idea of riding with a power meter like I do in my trainer. This power meter is relatively inexpensive here in the US compared to other pedal ones I’ve seen. Looking at the graph, yeah it is not perfect. In my case though, I think that is good enough. So I may just go for it. Thanks for the review
Is there any other difference between the 105 and the ultegra than the branding on the crankarm?
Great video! I have a 4iiii and I want to check it’s accuracy. The only thing I can compare it with is wahoo trainer.
How did you import these data to one chart to compare?
Thanks for explaining that 10 code 👍
Another great and helpful review Shane! Could I trouble you for a unrelated question. On zwift why can't I see average wattage for segments like I can out in the real world? I am using a bike without a power meter and a wahoo kickr.
One for Zwift Support. They've kept things very basic since their inception in regard to power metrics (no left/right, no averages, etc)
@@gplama I have to say I was Very dissapointed when I did the alpe and after the ride (after the descent) I checked the segment to see what my average wattage was going up and I couldn't see it! I felt like I did a good power (for me), it was a sad moment.
Missed the protocol the power figures were being recorded over - ANT+ power rises/drops on a standard channel period, shifted by +/- 1 second are going to be difficult to separate in any meaningful way. If a PM is ahead or behind in those cases ? Meh, probably more indicative of sampling than sensor placement.
ANT+
@@gplama I was wondering that as well which begs the question if retested on Bluetooth are the results the same?
@@thisandthatandotherthings Good question. 99% of what I do is over ANT+ indoors and out. If it was any different with Bluetooth I'd be pretty pissed (and have less time in the day as it'd require x2 the testing)
@@gplama I'd doubt there's any significant difference in the values over ANT+ and BTLE. There are places where things do differ though, e.g. sampling rate and timing and processing in the head-unit.
Bottleneck is invariably in the head-unit, and without firmware updates to those we'd not be able to get hold of the finer grained data that's actually available from the 'device' (trainer, PM etc) over either protocol.
One thing that *might * be interesting is to capture power from over both BTLE (via FTMS or CPP) and ANT+ (FE-C or Bike Power Profile) and combine them - you might get effectively a higher sample rate to look at sprints and such, pain in the arse for general work though.
Hi Shane, considering the ongoing issues with the P3, should I go after a discounted P2, a stages or an assioma Uno? I currently ride with MTB shoes, so the Uno would involve getting new shoes as well, which is why I was tending towards the crank-based ones. Is the Uno so much better it is worth the higher investment?
Congrats on the amazing work, really useful for us!
He still didnt message you back???
Thank you for the video, I’m trying to decide between this and the stages now that the price of the stages has just been dropped, I’ll be getting the Ultegra 8000 one, just wondered if you had a preference for one product over the other?
Not really. Single sided Shimano based power meters are all similar.
Great review, thanks Shane. Have you had a look at the dual-sided version? I assume it suffers from the classic Shimano crank right-side disease. Or have 4iiii applied some witchcraft to it?
I have. It’s included in my report on Shimano based L/R units.
@@gplama great, thanks, will check it out.
The 4iiii is horribly off on my bike. It was ok initially, but now it shows about 30w too little when I compare it to my kickr @200w in erg mode. My other Powermeters (quarq and SRM) are within +/- 1% with the kickr and show no leg imbalance.
Change the battery. If the battery 20-25% is below, tends to show lower watts.
Hey Shane. I’m in the market for a smart trainer... Leaning towards the Wahoo Snap... does it matter if it has a power meter or not if I already have the 4iiii on my bike?
does this thing measure the flex in the crank arm or something?
I believe they have what they call a tri-axial gauge.... so I'll roll with yes.
Unfortunately my brand new precision 2.0 by 4iiii is reading about 30% high. Disappointed, but I'm unlucky when buying stuff online.
The Karoo Hamerhead just added support for Varia and DI2. Can you review this?
I'm using one at the moment. Review soon..
Happy Days!
Hi Shane. Left between 4iiii , xcadey etc ... would you say their is a huge difference in performance
4iiii, Stages, Pioneer, InPeak, XCadey... all single sided left meters do the same... assuming they're accurate. My personal preference is the InPeak after they resolved the firmware issues and came up with some really good numbers.
@@gplama thank you champ Shane for your educated view as always ...
Hi S.Miller, great review as usual. Quick question, which would you recommend between this and the stages gen 3 left only. I started riding in April to lose weight and have done 5,580km and dropped 27kg so far. I now want to improve on my training and maybe gain better average and power so new bike and power meter. What’s your recommendation? Stages or 4iiii.
Thanks
First up - That's awesome progress on the weight-loss mate. I've no doubt that has been a ton of sacrifice and even more hard work. Well done. As for the technology - There's really not much between these two. Most companies who make a single side Shimano power crank have it nailed after many years of production. Either will do both ANT+ and Bluetooth too.
Is this still an issue to date or has this now been rectified by 4iiii looking for a dual sided power meter ready to do a charity bike ride from lands end to John o Groats over a 12 day period or should a just get the single sided. Any advice would be appreciated :)
Hey Shane, since the last windows 10 update that was pushed my bluetooth connection went from 100% rock solid to a 3-5 second drop out every 30 minutes or so. I remember Zwift sending an email about it, but haven't heard anything since. Is there any word on changes?
Nothing seen in the update list they publish. It’s something I’d hope they’d get on top of rather than sending ‘don’t upgrade your OS’ emails.... which from a security standpoint isn’t ideal.
Hi Shane, i have recently bought a gen3(single sided), which I am using with a garmin 530. There seems to be an issue with the scaling factor not being applied consistently. One moment it would need to be 0.5, stopping for lunch and restarting it would need a 1 scale. Have you heard of similar issues?
The Gen III unit has many issues I'm still waiting to be resolved. This isn't one of them I've encountered. Take this straight to 4iiii support.
@shane - you said in a reply in this thread roughly a year ago that you didn't really have an opinion either way between the 4iiii and the stages single sided (from my P1 pedals I know I'm not wonky). Is that still the case? 4iiii is sounding like the way to go currently.
No change there. I don’t recall either company doing anything new with their meters for a long while now.
Can you use this with 7900 Dura Ace chain set?
Hello no test planned for the Power Cranks - Shimano Ultegra Upgrade Kit from Specialized?
If I can get a hold of them, sure, I can test them.
One question: I have this 4iiii power meter and the Magene Gravet 2 smart trainer. Which one should I use as a power data source? 4iiii should be a bit more accurate but it's only one side power reading. Thanks.
I have the 4iiii and Elite Drivo using Trainer Road but in my experience their accuracy was about on point with maybe a 2-4 watt difference. If you're talking about controlling erg mode though the smart trainer is gonna give you a much better results. I tried using my 4iiii with power matching turned on and it kept hunting up and down during erg sessions so my final power would be about right but I'd be going up and down by 20+ watts.
@@VirgilOvid yeah it's about trainerroad. I've been using the 4iiii power meter as the power source and set the powermatch to auto to control the erg mode. The result is that the power reading fluctuates a lot in the range of +/-20w. I go on the Strava and see others have fairly smooth power reading on trainerroad and mines is very volatile.
I'm using a Wahoo Bolt to control a Tacx Flux. If I use the 4iiii the power will fluctuate +/-20W for me too. I don't feel any change in my legs, and when riding outside the 4iiii is reporting much smoother numbers. I'm ok with using power from the Flux, but I'm currious about how this work.
I use vector2s with trainer road on a Kickr17....I think ideally you would want to use the 4iii as the source of power as it will be the same source of power on the road as well. That being said I was also experiencing so wild power swings early on with power match in trainer road which made it difficult to use and very frustrating. It turned out in my case that I also had power matching turned on in the wahoo utility app and basically had the kickr and the pedals fighting over control. I am not sure if the magene has the same sort of app or not but perhaps support on trainer road can help sort you out.
I'm looking at getting either a Stages or 4iiii Ultegra left only crank for my TCR Advanced Pro 1 (2019) but the frame clearance looks awfully tight for the 4iiii. I have a Wahoo cadence sensor at the minute that just (& I mean just) fits. The pod looks a lot bigger on the 4iiii than the Stages. Did you have any frame clearance problems with this Shane?
No clearance problems in the TCR(s) I have. See my recent GRX power video for a comparison between a few different left only power meter pod sizes.
@@gplama Thanks for the reply Shane, will check that out.
How accurate is the cadence sensor and under what circumstances do you have to apply the zero offset and how long does that take? Any idea if the smoothed out the spikes?
Cadence is pretty much a solved problem across the board.....on averages. Zero before every ride is advisable. No idea on any updates on this. 4iiii haven't been in touch since posting my detailed report on the L/R units mid last year.
Great review, question: Which would you choose, 4iiii precision left side Shimano or Favero Assioma Uno? Thanks!
Either. Depends what suits your crankset or pedal preference.
@@gplama thank you, I really appreciate your help and your videos, good job!
Has anyone tried this on a bike with a BBRight bottom bracket (Cervelo R2 in my case)? I’m thinking of getting one but I’m not sure if it will clear the chain stay. The sizing guides on 4iiii website seems to say it will, but just barely
Shane iam so frustrated with my Assiomas....they were so promising but after moving from Virginia to California...they no longer wake up the app just never wakes them up and they never seem to be charging before they would charge from blinking orange to green blinking ....bot anymore...considering ditching for 4iii...plus it takes the folks at Favero to respond...what is the matter with them👿
If they're within warranty Favero should replace them.
@@gplama Your our Savior, I threw your name there and told them I found it easier to get help from an influencer than them Favero🤣...they been pretty responsive and apologetic...so GP...apparently one suggestion was to swap the USB charging cable, yep can't make that up and walla it started charging again! Insane but just know that's one of the basic trouble shoots...otherwise freaking taking videos while cranking wheel with them trying to log in deep state style to reset felt like a Nightmare to me🤣
Hi Shane, Thanks for the review. Do you know if the FCR7000 crankarm is compatible with my old FCR563/565. As my trainer is a vortex and wanted a more reliable power reading. Cheers
I have no idea sorry. One for 4iiii support who should be across this in a flash.
I do not have a proper headunit for now (planning on getting a wahoo elemnt). I am going with the strava app right now. Can i show the power directly in strava while recording the activity?
There’s no support for power meters within the Strava app at this point. This may change now they’ve added HR monitors back a few weeks ago.
Can you have an Easton Crank on the right and the Shimano Left power meter crank on the left, or must it be the same brand name?
Shimano cranks are compatible with Shimano cranks only, as I'm aware.
Is there a big difference in readings between Gen 3 Stages Left and 4iiii Left? Not talking about reliability, just accuracy.
Not that I've noted. Most left only Shimano based power cranks are within spec.
@@gplama Thanks Shane - I have two Stages Gen 3 left units and am generally 5050 or 4951. So I suppose no need to also get a 4iiii left side unit!
Hi Shane, thanks for another great video. In the market for my first power meter and it’s between the Assioma UNO pedals and this 4iiii Ultegra. Which would you recommend? Thanks
Entirely your call. Both single sided units test well.
Nice
which option did you go with Max? I am in the same exact dilemma! I signed up for the alert on the assioma UNO (seems to be 50 days before restock).
Khanh Van Ton I went for the Assioma’s and they’re great! Easy to set up, reliable and easily transferable between bikes 👍🏼
I'm after a single sided power meter, what's everyone thoughts? Stages or 4iiii?
What's the difference between this and the Specialized Power Cranks (Left only upgrade kit) which is also based on 4iiii Precision?
Off the top of my head, no idea. One for the Goolging.
what the differenec i saw some 4iiii and Cat eyes ,,, they are the same ?
Cateye are a light brand, iirc.
Hi Shane, how could I measure left right compensation? I have non drive power meter 4iiii dura ace. Thanks in advance
You’ll need a dual sided meter to accurately measure L/R balance.
Hi Shane I have the stages gen 3 and I see that the numbers are lower than my tacx fortex by 20-30w is there a way like the 4iii to do this adjustment manually through the app? Thanks in advance
I'd lean towards the Tacx being incorrect and needing adjustment.
@@gplama just to point out this is for the left crank stages only I don't have the duel sided PM is it still the same case where my vortex could be wrong?
I have a 4iiii ultegra and a power2max and the numbers aren’t the same. The 4iiii seems to always be under reading with about 10-15w. Which one could be reading faulty?
Dual sided 4iiii?
Shane Miller - GPLama no just left sided but my p2m says my L/R balance is usually almost the same maybe it might vary by 1% weaker for the left.
Is imperative to adjust the scale factor? I do test the 4iii single sided powermeter in a turbo trainer from tacx and if the tacx give me 200w the 4iii alwais shows 20 or 30w less... and is completely new 🤔
Which Tacx trainer model?
Tacx Flux
@@brunocosta3877 Then it depends how much you trust a trainer that isn't known for the most accurate numbers vs a single sided power meter.
@@gplama thanks for your reply.
My only doubt is if I should change the Scale Factor or not. I think I will keep it like it came from manufacturers.
I've been stumped, but for me I cant figure out why left handed power meters dont report accurately for me. I've tried 4 stages and assioma left handed power pedals and against my tacx neo and quarqs left handed always reads low, 40w at 300w range.
Could your Neo be incorrect?
@@gplama my tacx neo and 3 quarqs on 3 bikes all match nicely, but I can never get left sided only power to match. It seems like there is something to my pedal dynamic and my l/r balance is typically 47/53 so so at 300w that would mean +18w error vs left only. But 40w is the hard to account part.
Exactly the same thing with me. 4iiii reads higher in z1-2 then z3-4 it reads lower. VO2 max, 320 watts on Neo might read 300 on 4iiii. I've put it down to my right leg being more dominant when the going gets tough!
@@lebowskii98_9 Me too... I bought mine in 2018 (version 1.0?) and up until recently thought that it was fine, but then compared to a Wahoo Kickr, have found it reads high for low power (10-15%) and low for high power (7% out). Right leg more dominant - possibly. Can you get R/L split power analysis on a dual sided to confirm? I reckon I should do this too. Was going to send back, you have me thinking.
If you must pick a single sided pedal power meter would you go for Assioma Uno or Garmin V3s? The price is almost the same for both... I am looking for stability accuracy but mainly consistency and maybe next year want to buy the second pedal but today I do not have budget for dual ..
Your call. The Assioma pedals have been on my bike a lot more than the Vectors.
thank you.. This is all I need to know :)
Do you think it is okay to use ultegra 4iii meter on my bike that is using 105 groupset? Would there be difference in weight between cranks?
That works fine. Small weight difference but nothing of note.
@@gplama thanks. that should also be better if upgrade to a new bike with ultegra parts.
HI. Would you recommend the left side or dual side with this product? I
Never the dual for any Shimano based crankset with power meters installed after production.
@@gplama Thank you. Big fan of your videos
I’ve got mine for 8 months and the second time to change the battery, it dies 🤦🏻♂️🤦🏻♂️
So good luck to you guys
kin long lau I changed about 5 battery over 20000km and jet wash it no problem
Well if that did actually happen it would have been within warranty and be fixed or repaired for free, so what's the issue?
minnsminns I bought from probikekit and they can exchange the new one for me or full pay me back which takes me 6 months 🤦🏻♂️
So, if limited to choose between Stages and 4iiii? Coin flip?
Yep, for single sided Left only. Gen III Stages though. The InPeak impresses me a lot post their recent updates.
Shane Miller - GPLama thanks Shane, as always you are too kind to take the time to reply to all of our questions 😉🙏🏻🤜🏼
may i know if this power meter is compatible with all bike computer head units which measures power? especially to LEZYNE MINI. i am planning to buy bought of these units together. And also, will this power meter also be used in ZWIFT for my indoor rides? thanks
Yes. I'm not sure about the Lezyne Mini. If it supports power meters, it'll support this.
Shane Miller - GPLama so how about if this can be use in ZWIFT to register my wattage during my ride? Thanks for your prompt reply...
Yes, this works with Zwift.
Shane Miller - GPLama nice one. Just a beginner here in zwift. I’ve been watching all ur videos. Very informative. Keep up...
Would this fit a Schwinn IC8?
I have no idea sorry.
Is it compatible with oval chainring? If so, how accurate is it?
No. It’ll work... but it won’t be accurate.
You recommend and good power meter for oval chainring?
Favero Assioma support them. Power2Max also claim to support oval rings too.
Can I use the 4iiii Ultegra FC-R8000 Left Arm Powermeter with a Chainset: Shimano Ultegra FC-6800 Hollowtech II, 50x34T w/BB(BSA), Crank Length: 170mm-47/54cm?
I believe so.
does anyone know if it works with the canyon ultimates?
Markus Akne Vieider yes it does
I just bought one and after 1 hour or so of riding it start to read low values. Like 50 watts lower. I compared it with a smart trainer and another power meter just to be sure. Does anyone have see this problem?
One for 4iiii support.
@@gplama I bought mine in 2018 (version 1.0?) and up until recently thought that it was fine, but then compared to a Wahoo Kickr, have found it reads high for low power Z1 (10-15%) and low for high power Z4 (7% out). But this may be an imbalance in my legs?
@@AndrewRoberts42 There's a lot to dig into there.... single sided meters vs total power means there's always questions about balance. That's only resolved by having a true L/R meter... and having one of those means you don't need a single sided meter :)
If I know I'm about 52% power in my left, what do I change my scale factor to?
Lower.... maybe. Rarely are people always x% different. It changes based on power zones, cadence, terrain, fatigue, etc.
Yesterday I tested 4iiii utegra left crank against the tacx trainer and is giving me less 25-30W than the trainer... The crank is new... I'm very disappointed.
You’re measuring two different things. Left x2 vs total power. Which Tacx trainer out of interest?
@@gplama thanks for the response. I do the workout at the same time with 4iiii left crank and tacx flux. In the past I do the same using the same trainer but with quarq crankset and the values are the same on both devices.
Between 4iiii and the tacx flux is more than 6% less power in the 4iiii... 🙄
@@brunocosta3877 I bought mine in 2018 (version 1.0?) and up until recently thought that it was fine, but then compared to a Wahoo Kickr, have found it reads high for low power Z1 (10-15%) and low for high power Z4 (7% out). But this may be an imbalance in my legs?
@@AndrewRoberts42 In my case I think it reads only low for higher power... but for now I will give it a chance.
Should i purchase dual sided or single sided?
I'd go single sided with any Shimano crankset power meter. (until they change the design)
@@gplama in terms of pedals should i still purchase single? Or would it be better if its dual?
i have one on my gravel bike and so does my partner. after 4 months i had to send mine back because i was unable to calibrate it. now my partners is doing the same. :(
Hmmm. Not optimal. Did you have to return it to 4iiii or where you purchased?
@@gplama returned it to the bike shop. we put the OEM crank on while they sent the PM back to 4iiii . about 5 weeks later i got it back all working no problem since.
My 4iiii left side read about 6,4% over my neo 2T
installation torque is 👌 and my balance right left power is 49/51 and 51/49 depending of the ride or race i dont have a lot of diff. Its normal
or not thanks
You're comparing two different things. Left x2 vs total power. It's impossible to tell what's right or wrong without more data (dual sided cranks also measuring total power) or a set of power pedals with true L/R measurement to compare.
Shane Miller - GPLama Sorry, I misspoke. Last year I had the Garmin Vector 3 and I never had more than 51/49 49/51 between my two legs. This year I have 4iiii dual side powermeter, except that the right side is badly calibrated (shimano crankset) I think it's better just to take the left side but I have about 6.5% compared to the Neo 2T. Am I more accurate with the left side only or do I adjust the right side with scale factor? Thanks
@@jean-philippevenne4369 If the issue could be resolved with a scaling up of one side, that's how they'd be sold and there would be no issues. Entirely your call how to obtain more accurate numbers though.
Hey Shane, what was the worst instance of L/R imbalance you’ve ever encountered? I feel like my L/R imbalance changes depending on how much torque I’m putting down. So at the same power, if I try to spin up, (I think) my left leg drags and the power reading dips. I found it extraordinarily difficult to maintain a steady power up a slightly inconsistent grade during my 20 minute power test. I was around +/-35% from target, I would say. I’m wondering if this is due to my imbalance, the power meter or just my crappy pacing. Thanks!
There's no answer I can give that'll help here. Everyone is different. The solution is not to use a left only power meter (spider based, crank L/R, dual sided power pedals, etc).
Shane,
As always your reviews are very informative and entertaining. You are the go to source for me for sure for cycling gear and technology.
Maybe this is a dumb question but I believe I have as options, the Praxus + 4iiii for my Roubaix Sport but it appears that the Assioma Duo is not that much more expensive plus you have the advantages of two sided data and being more portable. I believe the duos are rechargeable where the battery for the 4iiii is only rated for 100 or so hours That equates to about 7 weeks of riding for me. If I am not so worried about the slight upcharge, shouldn't i just go with the duo?
Thanks in advance if you get to respond. Of course I would be anxious to hear what anyone else with knowledge might want to share or offer.
Cheers Jim. It's entirely your call which meter to go with. Dual (or total power) vs single sided will give more accurate results.
Wich one i get? 4iiii or stages gen3 both left crankarm
Either
Keith Wakeham ftw (remember to check out his YT-channel)
Yeah, I'm across that. See my report here: gplama.com/2019/06/29/shimano-crankset-power-meters/ This, and Keith's video is about the RIGHT side issues.
Would you like to know the power needed for climbing? Check out this video. Cheers
th-cam.com/video/OA7V3bq2VNE/w-d-xo.html
Spikier four eyed fish. Competing with Stages I'm guessing. Similar product and price so I think you would be better off with Stages
The InPeak2 still impresses me (post their fixes).
550 $ wow for what!
Pretty cheap for a power meter.
Hugo Young cheaper uno favero and pedals for free