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Very nice Bike. Is this a Medium+ ?

What I’d like to do: Murmur (or possibly Twist…) frame, 2 different sets of suspension and wheels for enduro/ XC. The minimal time it would take me to swap that out seems well worth it!

I remember when 100mm was your long travel bike... those were the days.

Could you run a 130mm fork on that?

Chain movement is taken up derailleur and free-wheeling hub.

Pedal kickback is not an issue during “normal” riding - it’s like coasting downhill and then trying to pedal in a low gear, the freehub mechanism will not “catch up’ with the wheel rotational speed!

That looks rapids, looks like it can take a beating too

I had the privilege of riding this very bike in the Starling 0:53 parking lot. It accelerates like a rocket. It’s so amazing that one frame can be build up is so many exciting ways.

"Not an enduro bike". Brother it's steel, I would be throwing myself off cliffs on this thing 🤪. I used to ride enduro trails on a 100mm 'XC' bike. Anyway looks like a blast.

Just say the weight!

I'll pinch that water bottle line, if you don't mind, xx

Each time Joe talks about wheel weight, I remember the articles of Bicycle Quarterly and Jan Heine, saying that wheel weight doesn't matter that much because bikes don't accelerate (or brake) as fast as a car or a motorcyle ... but from my personnal experience they make a bike much more faster than the same weight saved on the other parts of the bike ... I don't know wich one is true :D

I really like this bike, I've been drooling over a murmur for awhile. I'd really like to try it with a 52.5 stroke shock and a 140mm fork.

Absolute dream machine!!!

Chain slap or kickback its a drive train induced feel that many people do notice, and more on some suspension designs than others. It is likely more noticeable on a full sus vs a hard tail since due to the suspension absorbing all the noise the HT gets.

So whats referred to as "chatter" on a GP/other race bike- it goes away when the grip level drops. Someone interested could experiment with grippy tyres then immediately swap to a slick and see if it reduces..

Depends on the hub engagement and the kinematics of the rear suspension. Also it's less noticable, when going faster. As you can see, the PB video shows bikes going pretty fast with a lot of kinetic energy. It's easy for the chain to start rattling. Now imagine going down a steep technical turn, with a "root or rock drop". You're going slow and draging the brakes. Finally, the rear wheel drops off and hits the ground, the rear suspension almost bottoms out, then you feel the cranks being pulled back and your knee yanked violently towards your chest, maybe even hurting your ankle. I have had instances, when My right foot gets thrown off because of that. My Iron Horse Sunday had a slight tendency for pedal kick back and when I got My 2017 Mondraker Summum, that's when I noticed it the most. OchainR helps alot, but when I case a big jump, I can still feel My knee being yanked and it can cause My right foot to come off. Downhill bike will make it more noticable, because of more travel. My YT Capra has 170mm of rear travel, but doesn't cause so much problems. Maybe the different susp. design matters. I still notice it on My Capra aswell, but only slightly. If most of you ride 140mm trail bikes, chaces are, you won't notice it, especially at speed. Once you experience it, you will acknoledge it as a nuisance.

The issue is transmitting wheel forces into the chain to start with. The chain growing in the wheel path is what initiates the wave. The cause is incorrect wheel path and degradation in the drivetrain's orientation to the crank as the suspension compresses.

I absolutely love this shock on my enduro. Im 207lbs was bottoming out 2 different rockshox coil shocks too easy on 600lb 650lbs linear springs mrp 600lbs progressive springs i was so sad lol went back to air. Bought this shock put a 550lb progressive spring plus 25psi perfect now magic carpet and no more easy bottom outs!!!

Its not bullshit, but its blown out of proportions. People make such a huge deal out of it. Like if you dont compete in fkn redbull Hardline you dont need to care about that, spending huge money on hig pivot and sht.

This is true, even on my on-road bikes, that I've put massive cassettes on, do it after acceleration in high gears 🤓

I agree with your comments about wheels and stability. I have several Emtbs but my favourite setup is my old 2018 carbon levo now with 170mm Fox 38's, 29 x3.0 front and yes 27.5 x 3.25 rear tyre both with Tannis armour + tubes . Effectively 30 inch rolling heavy wheels with fantastic suspension effect within the big tyres at 16psi.Also I only run 25% sag front and 20% rear. At 62kg (nearly back to my birth weight) it all works well for me being extremely easy on my body punching though long 30min rock garden decents. Emtbs are a totally different experience to steam bikes where bike weight is your friend especially for lightweight riders. Silence is also golden. I also run a Rohloff hub for less vulnerability to sticks destroying the annoying fiddly derailleur . The early Brose aluminium case motor is really the Quietest, smoothest most natural feeling motor ever built and having 2 x 500wh batteries are better than one 700wh on the latest bikes. The forks and big tyres lift the bike make it more stable and with short 150mm cranks nearly eliminate pedal strikes. Thats why E=Mtb² for me and how and where I ride. The magic of Emtbs is that they turn us into gleeful kids again and broaden our ability to explore terrain multiplying the joy of one of mans greatest gravity cheating inventions the bicycle. They are a Time Machine. E=Mtb²

Its obvious to me that you think you have the perfect geometry of all time and it should never be permitted to change. There is a old saying... If carbon was any good they would make aluminium from it and if aluminium was any good they would make steel from it but unobtainium is the ducks guts." Do you agree. and is E=Mtb²???

Yes pedal kickback is a old school issue. It can't happen on a Emtb because of the sprag bearing. E=Mtb². A easy way to eliminate chain slap is to run the upper chain thru a floating length of 16mm garden irrigation pipe anchored loosely with a zip tie. As for all this high extra sprocket rhubarb... "hopefully they have Patented it to stop everyone else making the same mistake." E=Mtb²

Good analysis, I have a mullet bike and after riding a few months your pretty spot on. It's great for open, flowy trails and speed. But it is just a tad harder to control on jumps and techy rock or curvy trails, smaller tires are just easier to control. I like the speed/control combo of the mullet.

There’s an old saying… probably I read it in “Dirt Bike” or “Motocross Action”: “If, one week, Roger DeCoster showed up at the starting line with a turd taped to his helmet, next week everyone would have a turd taped to his helmet.”

I have personal felt it on a high pivot and it actually felt really bad ..

Pedal kickback doesn’t happen because the wheel can rotate away the chain growth. This is why you feel it the most under heavy braking. I would assume the pedal kickback would be much worse in huck to flat with the brakes locked up.

I did notice one thing from the pink bike video, Do kids not bend their knees anymore? When I raced MTBs in the 80's you used your legs to soak up the bumps. A little bit of "kick back" was the least of your worries. If you're worried about kick back, ride a Full rigid Reynolds bike for a season 😂 Kids today... ( Oh crap, I've become THAT guy)

Exactly. It's clutch tension and the chain flapping back and forth. Any time the chain is moving like that, it's mass moving in a direction and it carries momentum, if that is moving opposite to the direction you want the suspension to move, it's going to have a big effect. These are why the bike feels so much difference without a chain.

I felt pedal kickback in bumps while pedaling on a low gear when i changed from a 2006 specialized enduro to a 2006 Cannondale gemini. I felt it cause I wasn't expecting it (therefore i wasn't bias), it just felt strange, but I've never felt it while descending in a high gear.

You know, if you watch very closely, you can see in those "huck to flat" videos, at the moment they land, the chain is tight. They are descending very vertically, after that instance, they increase forward movement. Only some of the videos illustrate the pedals changing angles, but because the rider makes effort to brave for landing, he gets propelled forward.

Of course pedal kick back is an issue. The companies trying to sell you things to combat it say so.

Well also the back wheel can just turn a bit if the span between the crank and the cassette gets longer as described. But maybe some people can still feel something.

The only times I've noticed it (not saying it doesn't happen in other scenarios) is on a climb. I had just cleared an obstacle, so the argument that what I was feeling was just the obstacle making it harder to pedal is not true here. Right upon clearing this 4-6" tall log or rock, the rear wheel came down off that and my full weight compressed the rear suspension as I pedaled forward. Since I was moving at a snails pace, the effect was quite pronounced of the pedals rotating backwards.

Great video!

Good stuff, Joe. Thank you for these videos.

Well, ride any VPP bike especially one with links that rotate in opposite direction. Santa Cruz is famous for their pedal kit back it’s science, but most people can’t understand math and science so

I've personally never noticed kickback. The only stuff I feel is the chatter and vibrations of the trail.

unpopular opinion, pedal kickback is good, it keeps your feet parallel with the ground or the angle your body is weighting the bike through your feet constant as the rear of the bike and bottom bracket drops during the rear travel's wheel path.

0:56 now do the test with the wheel spinning, as it happens when you ride your bike. Surprise, no pedal kickback. Because the chain growth is not big enough to rotate the cassette so much that it engages the hub, at most riding speeds. Static analysis are so misleading... For a proper dynamic analysis watch: "What is PEDAL KICKBACK?...Should you care?" from Trail POV. O-chain is mainly an expensive placebo, improving a non existing problem.

"There is no mechanism for transmitting forces to your feet". I don't see enough arguments brought up in this video to back up this statement, there is no explanation really. If you had instant engagement in your freewheel and could not turn the cranks, you would block the whole rear suspension movement. That's the mechanism. Now you could argue how fast the coasting speed would need to be in relation to the tangential speed for the rear axle and gear ratio in order to catch up, but this is not mentioned in this video. Regarding chain movement I aggree, Steve from Vosprung Suspension did a great video on that. But also, besides inertia, pedal kickback could potentially contribute to the oscillations. I have a have used stfu (these are basically rubber rings that are mounted on your chain stay that limit the motion of the chain) and haven't really noticed any improvement except noise reduction. So the problem of blowing feet from pedals (flat pedals) when hitting exposed roots hard at moderate speeds still persists. I can imagine there are types of terrain you would never have the problem.

Wouldn’t a high engagement hub be a close runner-up for feedback through the pedals? After a hit/huck to flat/etc…pretty much anything besides freewheeling backwards will result in drive engagement feedback which will “kick” the pedals, however little that may be.

I have noticed kick back while heavy braking into corners, if you accidentally lock up the rear wheel and hit a bump your forward foot will lift up. You can’t push it back down again until you’ve let off the brakes a bit. I noticed this immediately after changing to hope brakes, much more powerful than what I was used to.

hahaha ok. who would've thought you'd feel feedback through your pedals when you're riding a rough trail? however the marketing department is loving this kick back to say their suspension is better so you'll but their bike. meanwhile, riders are eating that crap up and believing it. riding a bike through rough trail at speed should feel smooth!

Wicked topic. Good to see some people aren't getting caught up in the marketing 👍

Are there bike designs with shrinking Chain stays?

If it’s flapping chains, then it should be possible to feel it on a hardtail too. Can people feel it on hardtails?

So you would rather recomand a stfu than a o-chain?

Great points. One thing you miss is there is not chain tension in real world riding be the CASSETTE MOVES AS WELL. It's not a fixed point. pedal kick back is completely overblown