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@blackw0rx I weigh about 80kg. The wheel is 40kg and I'm using the S22 dnm rcp2s 240mm with 750lb spring. I tried with the standard 550lb spring but it was too soft and it bottomed out on big jumps.

@@eyeinthesky3013 Thanks. I weigh 65 kg, so maybe a 650 lb rate would be the way to go. However, coils over 600 lb are hard to come by, so perhaps a lower linkage ratio would be an option to go with the standard 550 lb or 600 lb coil, but will need some linkage prototyping.. I've studied your design, my observations are, that the pedals are 21 mm higher (23mm by cutting the stanchion minus 2 mm by swapping the O-ring for rubber). The clearance to the ground at the pillars should be 37 mm less compared to original (77mm added travel to original 70mm , -2mm rubber, -23 gain by cutting stanchions without clearance loss, -15 mm cutting pedal hanger, which means the pedals are 37mm closer to the ground when fully compressed (batteries have just 20mm lower clearance), which I find a good compromise proved by your videos riding it 🤩

@@blackw0rx wow that's a detailed analysis. I haven't even looked at it in that much detail. I when i ran the standard 550lb spring it was actually ok (very smooth on rocky technical stuff) it was only a problem on really hard landings. To stop it bottoming out i adjusted the compression damping to one click from fully closed. I did a few runs on my usual jump track and it was great. Really took the sting out of the hard landings but on the third run something broke inside the shock and the compression damping system locked fully open and the rebound fully closed. This was very bad and i immediately bottomed out really hard on the next landing and crashed. Shoulder still isn't right but since installing a new shock with 750lb spring the compression damping can be set further open and all is well. I would prefer slightly softer spring. I feel 650lb would be perfect but can't find one anywhere. You might even find the 550lb was ok depending whether you are doing big drops/jumps. One thing I have done since making this video is make a new set of links that has another hole for one end of the shock to optionally drop the whole wheel by 50mm to make it more stable for on road riding.

@@eyeinthesky3013 You can get one 650 lb coil within EU here on ekolka cz pruzina-tlumice-dnm-650-lbs--cerna--pro-kingsong-s22 I'm sorry to hear about the crash. I started jumping on Kuba linkage on my V2 master, currently I'm building V4 master with Julians +35mm travel and once done, I will be upgrading my current V2 master to +70mm travel inspired by your build.. I'm going to weld the battery holder to the 30x3 pipe to avoid relying on just one bolt. Although it's not the bolt holding the pedal hanger, it's actually the clamping with the plug inside the tube that supports the weight.

In theory there is around 40mm clearance on full compression which is a bit close for comfort. I had a couple of contacts when landing really hard using the shock with the 550lb spring but not enough to come off. Since changing the spring to 750lb it's been fine.

Unfortunately it's not just a matter of suppling parts. Quite a few of the existing parts need to be modified as well (Stanchions and pedal hangers). As I have a day job I just wouldn't have enough time to modify/supply the parts. The best way to get the mods done if you don't have to tools to do it yourself would be if you can find a machine shop that you can share the CAD designs with so that they could perform the necessary modifications and fabrication of parts. Sorry, that's probably not what you wanted to hear. It's an enough easy modification if you're experienced with CAD and metalwork and have the appropriate tools though.

No but I'll have a look to see if I made a circuit diagram. If I can find it I'll post a short video on the mod

Thank you. Means a lot coming from a fellow 'Master' expert. Yes the COG is very high now. It's horribly unstable going fast on tarmac. I don't go over 60km/h otherwise wobbles can come suddenly and are very difficult to control. It's great for the mtb trails that I go though and probably help manoeuvrability if anything.

@@eyeinthesky3013 I suspected the stability would be bad. I'm currently working on a low COG battery arrangement. I also really like the way you dropped the inside of the pedal hangers, that mount to the poles on the inside. to allow for tyre tolerances. I've done the same. Came to the same conclusion it's not required.

@@eyeinthesky3013 looks like there is no way to somehow lower the COG on a high travel suspension and so reduce the wobbling. But what if we put a small GYRO connected to the euc motherboard. So the motherboard detects wobbling (at the entry level) using it's xyz accelerometer and controlling the GYRO to eliminate wobbling. That way we can have a hight suspension travel and completelly forget about wobbling but even more we can eliminate the trolley handle as wheel now can stay up right in all directions and even follow you? :D

I like your thinking, but i think the best/simplest option would be a larger diameter wheel for greater rotational inertial stability. Lowering the battery height will help too but is unlikely to provide as much stability as with a larger diameter wheel. The trick would be to do this without losing avaliable tractive force* as is the problem with the Monster Pro. *Commonly miss named "torque" in euc chat. I.e. a bigger wheel diameter with the same motor will have the same torque but less tractive force available at the tire contact patch due to larger radius.

@@eyeinthesky3013 do you think the 22 inch wheel (like on Begode Master Pro) whould be a good choice for your begode master with 150mm suspension travel? in case if you'll have the same or even bigger tractive force as your master

Thank you. I'm a Mechanical Engineer so have been working with Solidworks for a long time. It's quite easy to learn but takes time to learn to be quick. I believe Fusion360 is a good option as it's free for hobbyists and is very capable.

All designs can be downloaded from the link in the description for free. Hope you can make use of them.

100% agree. Lighter wheels please! This is the next big challenge. Nobody needs crazy voltage wheels with 180km/h free spin speeds. >80km/h is really a very bad idea unless you're on a race track. What we need is lighter wheels with bigger diameter and more suspension travel.

@@eyeinthesky3013 It should be possible to shave off a lot of weight in the motor, since they have 8 spokes that are very solid. 4 should be enough. The motor on my Abrams is 27 kg alone! Lighter motor means less unsprung weight and more agile wheel.

​@JonahOnEUC I think most of the weight is in the steel stator and copper windings. The Master motor (C38), rim and tire (CST-186) weigh 14kg. I'm not sure that much weight can be saved without reducing the size of the stator and so loosing torque. Only way I can see that the rim tyre assemby can be much lighter is by using a belt/chain drive and a separate higher speed motor. I have designed and made one but it has issues. I need to improve it further but will release details once I get it working better.

@@eyeinthesky3013 We need an old broken motor we can split into pieces and see how the weight is distributed and where we can save. I think the very first EUC ever used chain drive.

@@JonahOnEUC I believe that some weight can be saved. I think Veteran put some effort into weight reduction for the Lynx but I'm guessing it's only a marginal saving. My belt driven wheel has a 4kg rim with 2kg tire. It has 130mm suspension but the motor is attached to the main chassis so only 6kg unsprung mass. It is a very nimble wheel and it is very easy to hop it up big kerbs. On paper it has similar torque to the Master but it has a strange problem with the controller that means it cuts out sometimes when you hit a bump. 😂 I'll get it working soon hopefully

I feel for you dude. 😪

Will do. Just need to find some time to bring it all together. I'll also release the Solidworks design once I'm done.

😂 yeah I like to have a near miss each time I hit the trails to keep them in check.

Great video nice jumps and more modifications😳

Gonna keep modding it until it breaks 😂

Yeah, that is typical Begode. It's like every wheel they make is a first off prototype. But that is to be expected in this market. EUC is still very niche and a very competitive market that relies on small numbers of sales to enthusiasts who just want the next best thing rather than the most reliable thing. This is not even unique to the EUC industry. If we wanted reliable cars we would all be driving Kia's with a 7 year warranty. Having said that, I love Begode wheels and have made peace that they aren't ever going to be perfect out of the box. It gives me the perfect excuse to upgrade the sh*t out of them. I've just finished an upgrade to this Master to give it 150mm of suspension travel. Will upload a video of that soon.

Yeah I would have preferred to use a smaller ratio but I already had the 190x51 shock so I designed it around that. Going to drop in a 750lb spring shock to see if that makes any difference as I'm sick of pumping the shock until veins are sticking out. Just had a look at the linkage generator. Really handy tool. One thing that would be really interesting would be if you could automatically plot the ratio throughout the travel so you could get an idea of how progressive the geometry is. The fundamental problem with the Begode linkage is that it is regressive so the shock/suspension travel ratio reduces as the suspension compresses. What we need for jumping/off road is exactly the opposite. The style of linkage that we are using is progressive, but not as progressive as the S22 linkage (which is why it seems to be preferred by most hardcore EUC jumpers). What are you making your linkages out of? I found aluminium was a bit weak around the pivots and had to strengthen them quite a bit as the first set I made deformed after a couple of hard landings.

@@eyeinthesky3013 yeah I can plot the full ratio... And have done it. You have a chat app if you up to share some finer details. As for 750lbs I think you will need 1000lbs. Ratio over 1.8 you need 900lbs + I'm running 1.7 ratio and 650lbs is a bit too plush for me at 75kg

I used stainless ones. 30mm OD 26mm ID is perfect. The only problem might be that the OD is actually slightly over 30mm. (mine were ~30.15mm) so I had to replace the original copper sliding bushings with polymer ones. Good luck with your modifications. 🙂

It's a Kenda Carlesbad tire. I bought it for my S18 originally so it would fit the master but it's awful on tarmac at low speed. It has far too much space between the knobs which are too flexible so steering at low speed is horrible. I tried it on the street outside my house and hated it so much that I immediately removed it. It might be OK off road but I tried the cst 186 after that and it was waaaay better so stuck with that.

@@eyeinthesky3013 I had something similar on my 16x few years back, 12-inch rim, you can get used to it actually though my initial impressions were the same. It's magical in deep mud and this is why I'm looking for a similar tire for begode master.

The high speed "cut out" is common to all EUC and is due to a fundamental limitation of electric motors. It's not really a cut out as such but is due to the motor reaching its maximum "free spin" speed and no longer being able to keep the rider balanced. Basically, as the motor spins faster it produces a reverse voltage that counteracts the battery voltage. When the motor speed approaches the "free spin" speed the reverse voltage is equal to the battery voltage there is no longer any spare voltage available to push current through the motor coils, no coil current means no torque from the motor. Unfortunately the EUC relies on having some spare torque available to keep balanced, so balance is lost and the euc rider has a bad day. It's a really horrible feeling when the pedals go soft and you start falling forwards, when it happened to me at 60km/h I was lucky to only break my wrist as I wasn't wearing any safety gear. The beeping from the EUC is it's way of warning you that it's about to happen, ignore the beeps at your peril!!

@@eyeinthesky3013 Great response very informative. Thanks

It's in Co. Wicklow in Ireland. Ballinastoe MTB trails. I'm so lucky to have them close to where I live.

I'm not sure I could do it cheaply enough for people to be interested. Plus it's not really a plug and play mod as there are mods to do to the Master chassis for it to fit. It requires a basic hobbyist level of experience with metal working and mechanical design to get it installed and working nicely. I'd be worried that people might render their wheel unusable if someone attempted it without the required level of experience.

I use a Skydio2 for this kind of stuff, it has full 360 obstacle avoidance and can follow you autonomously. You keep a small beacon in your pocket that transmits your gps coordinates to the drone to allow it to follow you even if it can't see you. It came out a few years ago but sadly is now discontinued. It's significantly better than any DJI drone for obstacle avoidance and it's ability to follow through tight spaces.

@@eyeinthesky3013 Thank you. It should have occurred to me that only the Skydio can make such rapid movements while tracking 😊

Thank you. I've benefited greatly from so many youtube video on how to solve various problems I thought it was time I gave something back.

I think we will start to see more upgrades and diy euc soon. The OneWheel community is starting to adopt the VESC opensource controller to bypass the restrictions on modding the stock OW from Future Motion. Its actually relatively easy to replace the controller on an euc. Many of the VESC controllers come with and IMU and the firmware includes the balancing code. I replaced the controller of my old mSuper V3 and it works better than the stock controller with a higher top speed (vis field weakening) and the ability to customise the responsiveness. If I owned an S22 I would consider replacing the controller with this one alienrides.com/products/3shul-vesc-motor-controller-cl350-v4-preorder. From my understanding the weak point of the S22 is the controller.

I agree that trail riding is not about speed but I think the maneuverability of the T4 is more about the reduced rotational inertia of the C30 motor rather than the slightly smaller diameter wheel (though this will help). The C30 motor in the T4 will have a significantly lower rotational inertia/gyroscopic force/torque and so be much easier to whip around than the C38 in the master. The compromise made with the T4 is to achieve acceptable 'tractive force' from a lower torque motor at the cost of (unneeded) top end speed by reducing the effective lever arm length (wheel radius). I think the ultimate trail EUC would have a significantly larger, but much lighter, diameter rim to achieve a low rotational inertia. There is a reason MTB wheels are 27 or 29 inch and not 18 inch, and MTB are much more maneuverable at speed >20km/h than any EUC. I have an S18 (exact same rim diameter and CST-186 tire as on the Master) and it is incredibly nimble (likely due to <30mm stator/magnets) and small/light batteries. I'm fine with the top speed of the S18 too but the lack of torque is unforgivable, hence my "upgrade" to the Master. We are still at the "Klunker" stage of EUC as was MTB in the 1980''s. Exciting times, I can't wait to see what's next!😁

@@eyeinthesky3013 I dunno if your arguments proposed hold water so I'm not gonna debate it. All's I can do is provide my own experiences having owned a s18, RSht, EXN (hs & ht) & now a T4 & ex30. I used to think the RSht was the perfect pkg for trails cept for low peds & lack of suspension. IME the T4 isnt much lacking in torque vs RSht but despite being ~10lbs heavier, feels much lighter & def more nimble & hence more controllable. Perhaps its my ave 170ish lbs weight but for me, torque isnt the T4's weakness but instead its ave suspension. Still I lov riding it on dirt esp gnarly technical mtb single tracks. Much better then the RSht. Dont forget, a smaller wheel has a very significant mechanical advantage as well. IMO my s18's suspension was trash & the torque (or lack thereof) was pitiful. T4 is multi levels better & amazingly, does not feel heavier despite being 20lbs in actuallity. IMO IME ofcos

​@@eyeinthesky3013 Good points. Becomes a balance I guess, Extreme C40 has more torque than C30, but you have to decide whether thats worth the extra gyroscopic force and weight in general. The extreme has a lot more torque/top end than a T4 but will that actually translate into faster times through a singletrack course, given the fact that its heavier and has more gryoscopic force like you point out? Thats probably completely dependant on the track (and rider). Especially if you ignore the fact that extreme has more up to date suspension etc.

@@yarnfBtwn the T4 & Extreme, suspension aside, I say it would depend on the type of track. On super tight very technical multi terrain with altitude changes, I say the T4 will be competitive esp for lighter riders. My T4 does 90% of the dirt rides I do well but I must admit that final 10% is calling out to me which is why I'm seriously pondering on a winter order of the Extreme in time for spring '24. The better build, the better suspension, the extra power/torque, the extra batt/range & the higher topend are very enticing. But the extra 20lbs is def giving pause. Regardless, I lov riding my T4 as a monowheel mtb. Dont need more speed but a bit more torque is always nice & the all metal + cnc stuff is great tho I havent damaged my plastic T4 as yet despite innumerable offroad dumps

​@@scottsum1319 Ya agree with all that. And even as an extreme owner: if they made a new version of the T4 with the new Extreme build quality/upgraded suspension/CNC etc I'd be all over it.

Thank you for your kind comment. The trail is in Ballinastoe, Co. Wicklow Ireland. I would love to design the ultimate electric unicycle so, Begode, if you're listening, sign me up. 😀

So much fun and I don't have anything better to be doing at the moment. 😅

@@eyeinthesky3013 You mean there are better things to do than this? I doubt it! 😀

You are welcome. Happy modding! 😎

You are very welcome. I just wanted to let people know it is possible and to help them get more from their EUC. 😊

Thanks dude.

?? I don't understand the question.

Is it filmed at bike park wales, in Merthyr Tydfil?

@Marcus-yt2sm ahh. No, it's across the water in Ballinastoe in Co. Wicklow, Ireland.