True "Mountain Bike" Style EUC

[cegli]

I was wondering if anyone else rides steep tech mountain bike trails on their EUC and is also dreaming of a "true" mountain bike style EUC?  The current wheels are too small for tech, and they're heavy, with way more power/range that is needed for real tech/flow trails.  I'd be willing to trade-off a lot to get a lighter, larger diameter wheel.

My target specs would be:

• 26"/27.5" low weight mountain bike rim (30mm width) , tubeless with mountain bike spokes.
  • Maxxis DHF EXO+ Tubeless 3C Tire, 2.5"
• Very high torque, low speed motor (to account for the huge wheel)
• Max speed ~40km/hr, beeps start at 30km/hr (help get the weight of the motor down)
• High voltage, low mAH battery pack, to once again help with weight
  • 151.2V split into 2x 18S1P packs to get weight and bulk waaay down.
  • High power 50S cells (or better) would allow a configuration like this to be safe
  • ~25km range when ridden at low speed, like one typically sees when mountain biking
  • On-top "quick connect" 36s1p range extender to boost range to 50km for super long rides.
• Durable metal frame, controller on side of EUC to cut-down stand over height
• 150mm travel - fork style suspension
  • Air spring (weight savings)
  • One fork air spring, other side compression/rebound damping, like a high end mountain bike fork, with metal bridge in between (weight savings)
  • Service kits sold for damper/air spring (like a mountain bike fork)
  • High riding pedals, which are still stable due to being below the axle on such a large wheel
• 55lb max weight, stretch goal to 45lbs

What do people think?  I think the weight is possible.  So much of the weight right now is battery, huge motors, and the extra metal needed to encase a large amount of batteries.  The non-ultralight e-mountain bikes weight around 52lbs, and they usually have 700Whr batteries and 2x 29" wheels and a much bigger frame + drive train, handle bars, brakes, dropper post, etc.  We'd need to have a bigger motor (for safety), but could save on all the rest of the stuff that could be dropped.

I'm not certain about the torque needed for a wheel that large.  I think it'd be possible with a 150V motor/controller.

I almost want to build it myself, but don't have the spare time right now...  Would be pretty cool though...

Questions/Comments I'm guessing are coming:
That's way too slow!
---EMTBs are limited to 250w and techy descents barely go above jogging pace most of the time.  Riding faster than this on the climb trail is fairly anti-social anyway, since most bikes are going closer to 10km/hr, and emtbs top out around 20km/hr on steep climbs due to their small motors.  Many mountain bikers were already upset at the idea of a 250w motor on the climb trails, for a bit of perspective!

The range is too low!
--Go on trailforks.com and look at most of the routes that include black diamond tech.  You'll see most are well under 15km, let alone 50km.

That small of a battery pack wouldn't be safe on high power wheel
--50S cells can handle a 30A discharge with 93% of capacity, meaning even a 36S1P pack could pull ~4000 Watts while at nominal voltage and ~3200 Watts when close to dead.  Regen braking is a little closer to the limit (~1200W allowed with "step charging").  Not sure how much regen occurs braking down the average trail.

--Why such a big wheel?
The mountain bike world has slowly moved from 26"->27.5"->29" wheels because they can roll over roots/pits/chunder faster while transmitting less shock to rider.  Almost all enduro bikes sold now come with a 29" wheel up front.

--The standover height would be too high
I don't think so.  People ride 29" mountain unicycles, and people ride 36" wheeled street unicycles.  26"/27.5" would work fine assuming correct pedal height and nothing above the wheel except a mud/leg guard + fork bridge.

--Why so much suspension?
150mm is the standard for enduro riding.  I assume a similar amount would be ideal on an EUC.

--You can't just plug in a second parallel battery on top without causing problems, due to mismatched voltages between the two packs
The eMTB world has already solved this with circuitry in between the two battery packs that deals with this.  Look up mountain bike range extenders.

--This wouldn't be good for jumps
Agreed, this would be an "enduro" focused EUC, not focused on dirt jumping, urban riding.

--This would be a bad street, commuter, or racing wheel
Yep

--This kind of setup isn't needed on the hard-pack smooth, flowy mountain bike trails that are around me
Yep

Edited November 18, 2023 by cegli

[Cerbera]

2 hours ago, cegli said:

I was wondering if anyone else rides steep tech mountain bike trails on their EUC and is also dreaming of a "true" mountain bike style EUC?

I enjoy watching other people tackle that sort of thing, but don't consider it any of my business to try and do it on an EUC, let alone one as patently unsuitable for it as mine (and my level of skill on it!). I've always thought that the 2 wheels of mountain bikes play such a large part in making these difficult technical challenges doable at exciting speeds that they might not apply to monowheels which are very much more at the complete mercy of the one patch of ground we are in contact with at the time...

But don't let me put you off - I am beyond intrigued to see how a 29" wheel would look and perform practically ! Definitely agree someone should build one, and it's impressive the amount of thought and consideration you have put into the possibility; I hope you get time to try...

 

Edited November 18, 2023 by Cerbera

[Whalesmash]

My main gripe is that maneuverability suffers the larger the tire gets. Large tires are a good for rolling over things, but they produce significantly more gyroscopic effect (technically again good for rolling over things) but not so great for turning. Anyone who has ridden the old 24" monster pro knows what it's like. Throwing that thing around a corner is a full body lean, especially for a 140lb rider like me.

The other concern is the poor ergonomics. As the tire size increases, the shell has to grow taller in tandem and starts knocking your knees or worse yet your thighs. Much higher than that, it's going to get uncomfortably close to bonking your delicates. I guess this depends on the pedal placement too, but there's a lot of trade offs for raising pedal height, and most people don't like the feeling of instability. I personally put master pro adjustable pedals on my master when I changed it to a 100mm travel suspension, and the increase in pedal height took me a while to get around to, but once I was there, the extra clearance has been amazing. That said, it can still feel very unstable at times. 

All that said, I'd love to see a wheel like what's being proposed, despite how skeptical I am of such a thing. Unfortunately, the number of riders like us who are looking for such a thing are regrettably few.

[cegli]

28 minutes ago, Whalesmash said:

My main gripe is that maneuverability suffers the larger the tire gets. Large tires are a good for rolling over things, but they produce significantly more gyroscopic effect (technically again good for rolling over things) but not so great for turning. Anyone who has ridden the old 24" monster pro knows what it's like. Throwing that thing around a corner is a full body lean, especially for a 140lb rider like me.

My thought was that the low speeds + low weights involved here would significantly lower the amount of gyroscopic force.  Same way that it's still easy to turn a mountain bike, even with big 29" wheels.  You bring up a good point though, perhaps it would be worth it to move from a hub motor to a mid drive motor.  That way you could gear it and you wouldn't have almost no gyroscopic effect, since you've removed the spinning weight of the motor.  You'd also remove almost all the "unsprung mass" from the suspension, which make the ride a lot better.  Downside is you need some sort of gears/transmission... More moving parts.

You're totally right that larger diameter wheels are harder to manage though.  I used to do some mountain unicycling, and it was a lot easier to rolling hop off drops and do a 360 on a 20" wheel than a 26" wheel.  On a mountain unicycle, you get used to it with time.

28 minutes ago, Whalesmash said:

The other concern is the poor ergonomics. As the tire size increases, the shell has to grow taller in tandem and starts knocking your knees or worse yet your thighs. Much higher than that, it's going to get uncomfortably close to bonking your delicates.

Yeah, part of the design would be to move the controller off the top of the unicycle and onto the sides, where you've saved space by having less batteries.  The pedal height would come up along with the wheel.  Here's a person on a 27.5" mountain unicycle, you can see there's still tons of clearance:

28 minutes ago, Whalesmash said:

I guess this depends on the pedal placement too, but there's a lot of trade offs for raising pedal height, and most people don't like the feeling of instability. I personally put master pro adjustable pedals on my master when I changed it to a 100mm travel suspension, and the increase in pedal height took me a while to get around to, but once I was there, the extra clearance has been amazing. That said, it can still feel very unstable at times.

As your wheel size goes up, the instability at higher pedal height goes down, due to you still being X" below the axle.  As soon as you get above the axle, the instability increases a lot.  With a large wheel, you could raise the pedals a ton without losing stability.

28 minutes ago, Whalesmash said:

All that said, I'd love to see a wheel like what's being proposed, despite how skeptical I am of such a thing. Unfortunately, the number of riders like us who are looking for such a thing are regrettably few.

Very true, I'm guessing there wouldn't be too many people that would appreciate a true "hardcore" mountain EUC.

52 minutes ago, Cerbera said:

I've always thought that the 2 wheels of mountain bikes play such a large part in making these difficult technical challenges doable at exciting speeds that they might not apply to monowheels which are very much more at the complete mercy of the one patch of ground we are in contact with at the time...

On steep descents, almost all braking is done with the front wheel on a mountain bike, due to the shift in weight forward.  Many mountain bike coaches will tell you on steep slabs to not use your rear brake at all when you're learning, to get you to understand how much braking power you have purely with your front brake.  I bet you could send an ultra steep slab with no issue on an suitable EUC.

 

Edited November 18, 2023 by cegli

[Planemo]

As far I as I am aware, the biggest problem with going much bigger than 22" is the 'angle moment' (not sure thats the right terminology!) It's the reason why an MTen feels far zippier than a Monster Pro. One person will be able to answer this... @mrelwood are you in the building?!

[Vince.Fab]

If you haven't had the chance to try an Extreme, I think it's what you are looking for as far as ability.  I went from am RST to an Extreme and that brought my trail riding abilities to a whole new level.

I went on a few group rides with a fast E-mtb group on highly technical trails and was able to keep the pace without a problem.  They were very surprised that it could even keep up and we even did the rock garden trails, black diamonds. 

The weight and wheel size wasn't an issue and I've been liking the way the smaller wheels handle strikes and quick repositioning moves.  Long travel is import and it should be progressive.  I've designed a 150mm upgrade for the Extreme to really push boundaries. I also think that's going to be a sweet spot for fast/tech mtb trail riding.  As far as torque goes, imo we are currently traction limited. 

With tire size,  I think you'll want more width.  Tubeless would be nice and running an insert to help mitigate rim damage at lower psi.  A much larger wheel would be interesting if they could get the tq high enough. 

Really looking forward to when VESCs can reach these higher volts reliably.  Being able to tune the motor will be crucial.... that's if you can find the right hardware. 

 

 

Edited November 18, 2023 by Vince.Fab

[Rawnei]

We ride our wheels like mountainbikes around here, the only difference would be you have to watch out for pedal clips.

[Funky]

This would be MY dream wheel!

1. Big wheel - check. (The bigger wheel - the better.. It simply rolls over everything!)
2. 40km/h speed - check. (I'm ridding 25-30km/h most times.)
3. Small battery pack - check. (I need daily 5km..)
4. lightweight - check. (Under 55lbs - preferably around 45lbs.)

Heck with 26/27.5" wheel i would happy even without suspension. (More weight savings.)  Can someone make it please?

 

 

[techyiam]

7 minutes ago, Funky said:

Big wheel - check. (The bigger wheel - the better.. It simply rolls over everything!)

Perhaps, you are thinking the grass is always greener on the other side of the fence?

7 minutes ago, Funky said:

(I'm ridding 25-30km/h most times.)

At these speeds, I not seeing the need for a big wheel.

Surprisingly, I am not noticing my 22" Abrams being that much more comfortable over bumps than my V12. On most bumps, it does soften the edge a bit. A negative for the V12 is that it moves around a bunch more. But one can get used to that.

In terms of comfort, my S22 with a 300 lbs spring and where the sliders have been cleaned and lubed, is way more comfortable going over bumps than both my Abrams and my V12, hands down.

Nah, looking back, for 30 km/h or less, I wouldn't get a suspension wheel, nor a big wheel. I would stick with my V12. Once dial-in, the V12 is a nice riding wheel.

[Funky]

1 hour ago, techyiam said:

Perhaps, you are thinking the grass is always greener on the other side of the fence?

 

That's how the saying goes.. So it must be true!  

Sure 16" is pretty nimble. And on tight turns it's hands down better than some 20"++. (BUT i said my dream wheel.. As in my riding style and the paths i take.. I have no turns almost! Only going straight more or less. As for turns - if i could take turns with regular bicycle - i think i could take ANY turn with one wheel, be 16" or 26".) 

1 hour ago, techyiam said:

At these speeds, I not seeing the need for a big wheel.

Surprisingly, I am not noticing my 22" Abrams being that much more comfortable over bumps than my V12. On most bumps, it does soften the edge a bit. A negative for the V12 is that it moves around a bunch more. But one can get used to that.

In terms of comfort, my S22 with a 300 lbs spring and where the sliders have been cleaned and lubed, is way more comfortable going over bumps than both my Abrams and my V12, hands down.

Nah, looking back, for 30 km/h or less, I wouldn't get a suspension wheel, nor a big wheel. I would stick with my V12. Once dial-in, the V12 is a nice riding wheel.

I would disagree riding 16" vs 18" there's quit a difference. (Going over bumps, etc..) Even now if i compare the same roads where i was riding for decade with my 29" MTB. And now with my 18" euc. There's quit a difference. (Sure i get it's 1 wheel vs 2 wheels, seated riding, etc.. BIG DIFFERENCE - i get it!) But simply rolling over things like curbs, railroads, potholes, 29" does it way better than 18". YOU can't even argue here! (And i liked to ride my MTB shocks locked.)

Also how high psi do you ride your 22" and 16".. If you ride around 35-40psi where tire is like solid rock. No wonder.... With bigger wheel you can run lower psi, meaning it will be softer ride overall. (If both wheels have no suspension.) Also need to take into mind rider weight. If you are under 200lbs and ride 35+psi. Yeah, i'm not even gonna listen to you.  

Yes you can even ride 10" Mten4 at these 30km/h speeds. No problem.. But i'm not you and i have my own wants/needs. Could i ride your loved V12 without problems - ofc. Do i want to? If i had choice of riding bigger wheel at same weight? Not really..

Also in winter riding bigger wheel is simply better than some small narrow tire. Tire contact area on ground is better on big one. (Big tire = big contact area. Small tire = small contact area.) More tire studs on ground, etc.. Heck even small things like going over foot high/long snow barriers.

Edited November 18, 2023 by Funky

[techyiam]

2 hours ago, Funky said:

Also how high psi do you ride your 22" and 16".. If you ride around 35-40psi where tire is like solid rock. No wonder.... With bigger wheel you can run lower psi, meaning it will be softer ride overall. (If both wheels have no suspension.) Also need to take into mind rider weight. If you are under 200lbs and ride 35+psi. Yeah, i'm not even gonna listen to you.  

On the Abrams, the tire pressure is 25 psi. I would have gone lower if I could.

On the V12, the tire pressure is 30 psi.

2 hours ago, Funky said:

I would disagree riding 16" vs 18" there's quit a difference. (Going over bumps, etc..) Even now if i compare the same roads where i was riding for decade with my 29" MTB. And now with my 18" euc. There's quit a difference. (Sure i get it's 1 wheel vs 2 wheels, seated riding, etc.. BIG DIFFERENCE - i get it!) But simply rolling over things like curbs, railroads, potholes, 29" does it way better than 18". YOU can't even argue here! (And i liked to ride my MTB shocks locked.)

If you have experienced the difference, then it is all that counts. That's your 18 XL is significantly better than your Dad's 16" wheel.

My point is that it may not be necessarily be true for a bigger wheel to ride that much better over bumps than a small diameter tire. There are other factors.

In my case, I think I have a good non-stock scooter tire on my V12, and the stock tire on my Abrams is not that great for bumps.

Another note: the 16" V12 with stock tire is much better over bumps than the 16" Begode T3 with stock tire. And the scooter tire is better over bumps than the stock tire on the V12.

For some reason, having ridden the Abrams for a while than switching back to the V12 on the exact same routes, the Abrams basically softens the edge but I still feel the jolts in my joints. It isn't that much better. The big difference though is that the Abrams doesn't move around much. Meanwhile, the V12 is constantly jiggling around on rough roads.

Edited November 18, 2023 by techyiam

[Funky]

1 hour ago, techyiam said:

For some reason, having ridden the Abrams for a while than switching back to the V12 on the exact same routes, the Abrams basically softens the edge but I still feel the jolts in my joints. It isn't that much better. The big difference though is that the Abrams doesn't move around much. Meanwhile, the V12 is constantly jiggling around on rough roads.

Gyro effect of bigger wheel at speed.. Bigger weight, of bigger wheel. Many things at play..

Also you are talking about "comfort", i'm simply talking about the "rolling over" aspect. 10" wheel going over a brick vs 22". My money is on the 22".  

I still would love to see a 18" or 20" lightweight ~40km/h speed, ~1000Wh wheel.. Sadly the bigger the wheel diameter - the more power is needed to turn it, at witch point lightness goes out the window. And then we have another 70-100lbs wheel.

1 hour ago, techyiam said:

My point is that it may not be necessarily be true for a bigger wheel to ride that much better over bumps than a small diameter tire.

How it may not be true? It's a simple fact that bigger wheel rolls over things better than smaller wheel. Take again the "brick" example.. Even if we look at comfort aspect. You yourself said:

1 hour ago, techyiam said:

Abrams basically softens the edge but I still feel the jolts in my joints. It isn't that much better. The big difference though is that the Abrams doesn't move around much. Meanwhile, the V12 is constantly jiggling around on rough roads.

My point stays - i would gladly take V12 with 22" wheel instead of 16" wheel - IF i had a choice.(At same weight.)  But that's me. Because i like the greener grass that is on other side of the fence.  

I don't need the "fast" acceleration that smaller diameter wheels give. I'm a cruiser.. For that the bigger diameter - the better. Also smaller wheels take any "micro movement" as an rider input. Where on bigger wheels you need to lean more and at turns sway all your body weight around - Which i like.

16x2.125" vs 18x2.5" wheel.. I notice quite a difference. Maybe because i'm 280lbs and ride around 30psi. Who knows.

Edited November 19, 2023 by Funky

[techyiam]

9 minutes ago, Funky said:

I still would love to see a 18" or 20" lightweight ~40km/h speed, ~1000Wh wheel.. Sadly the bigger the wheel diameter - the more power is needed to turn it, at witch point lightness goes out the window. And then we have another 70-100lbs wheel.

An 18" or 20" is a safe size wheel to get because you never know what the manufacturer could have done to screw things up in some fashion. 

A 16" wheel could work if done properly.

You said that you ride normally between 25 km/h and 30 km/h. And here is the key point.

Between 25-30 km/h, it isn't really fast. But it is fast enough on lousy roads to give jolts to riders who knees and other legs joints that are not strong and healthy, to feel some pain.

The other thing is in your older post, you talked riding on sidewalks and such. Do you really encounter "big bumps" or potholes on your last mile device to the train station?

If not, not sure how a big diameter wheel is going to help on smooth pathways.

17 minutes ago, Funky said:

My point stays - i would gladly take V12 with 22" wheel instead of 16" wheel - IF i had a choice.(At same weight.)  But that's me. Because i like the greener grass that is on other side of the fence.  

I don't need the "fast" acceleration that smaller diameter wheels give. I'm a cruiser.. For that the bigger diameter - the better. Also smaller wheels take any "micro movement" as an rider input. Where on bigger wheels you need to lean more and at turns sway all your body weight around - Which i like.

On paper, what you say might make sense. But sometimes in reality, it is hard to know without testing them out back-to-back.

[Funky]

36 minutes ago, techyiam said:

The other thing is in your older post, you talked riding on sidewalks and such. Do you really encounter "big bumps" or potholes on your last mile device to the train station?

I have little bit of gravel road.. Which have quit big potholes. There's no going around them. More or less i drive true them. Also railroad and some smaller curbs.

Doable on my 18". Even going same 20-30km/h speeds. Doh i feel those "jolts".  (Back of my mind i think i'm gonna bend axle or crack it.. And one beautiful day pedal breaks off mid ride!) Bigger tire - less of those "jolts" and more going over.

I'm personally waiting now for the KS-S14 to be released. S16 type build, but lighter. I bet it would be better over my 18" as it has suspension. (Doh i'm still not sold on the idea of having one.)

[techyiam]

1 hour ago, Funky said:

I have little bit of gravel road.. Which have quit big potholes. There's no going around them. More or less i drive true them. Also railroad and some smaller curbs.

If you have fair size potholes, big wheels win.

Hard to say about train track crossings since it depends how smooth they were built. But you can go slower for crossings and small curbs.

Even with my Abrams, I don't do curbs. I baby my wheels.

I don't even do curbs with my S22, even with suspension travel set at full travel, but with 300 lbs coil spring. I guess it is out of habit. But should I get lazy, I may drop down one. Usually, I avoid curbs.

1 hour ago, Funky said:

Doable on my 18". Even going same 20-30km/h speeds. Doh i feel those "jolts".  (Back of my mind i think i'm gonna bend axle or crack it.. And one beautiful day pedal breaks off mid ride!) Bigger tire - less of those "jolts" and more going over.

I don't feel jolts since I have been riding the S22.

Regarding the V12 being pretty going over bumps, the firmware settings help too. When I first unboxed my V12, it was not good as now. But since the latest firmware (out for a while now) and the fairly new Inmotion App, things improved a lot. The wheel is significantly peppier, and excellent braking, and softens the bumps even more.

Going over bridge expansion joints of this one bridge, travelling at similar speeds, the Abrams and the V12 is about the same overall. The feel of the jolt is different, but the intensity overall is about the same. My Begode T3 would give me bad pain going at slower speeds.

2 hours ago, Funky said:

I'm personally waiting now for the KS-S14 to be released. S16 type build, but lighter. I bet it would be better over my 18" as it has suspension. (Doh i'm still not sold on the idea of having one.)

I think S16 or S19 could be good wheels if only Kingsong can improve QC, and swap in a fender with deep side skirts.

I like the way the S19 rides.

If KIngsong does make an S14 based on the S16, I am not sure how are they going to reduce weight and still keep the price in check.

[Funky]

 

7 hours ago, techyiam said:

Even with my Abrams, I don't do curbs. I baby my wheels.

I was talking about "small curbs" that are 2 finger high.  I don't do regular curbs at all. I also baby my wheel.. (I also slow quit a bit down almost to running speeds.)

7 hours ago, techyiam said:

If KIngsong does make an S14 based on the S16, I am not sure how are they going to reduce weight and still keep the price in check.

Smaller over all. Less battery, smaller rim, motor having less copper spins in it.. It all saves weight. Heck for smaller wheels they could even go back to plastic builds... We don't need metal here. I just hope it will be around 45lbs. Otherwise duck it.

Anyways we are getting off-topic to much.. On topic: I like big booty wheels which are lightweight.  

[skunkmonkey]

It would be interesting to see how much torque they could get with a 29" wheel if they didn't worry about distance. My guess though is not much. Torque = r*F*sin(theta), since the motor radius is small, the force needs to be very large to move a larger diameter wheel. We see this on the V13, the low-end torque is pretty low from what I've heard.

[Hellkitten]

29 minutes ago, skunkmonkey said:

We see this on the V13, the low-end torque is pretty low from what I've heard.

It is. 

[Panzer04]

Those are pretty big asks.

1) Massive wheel precludes a Direct drive motor (literally all EUCs today). A geared hub might be possible, but it's not an off the shelf part by any means and has many drawbacks (reliability, efficiency, etc)

2) Bigger wheel restricts positioning around the wheel - i'd be curious how easy such an EUC would actually be compared to a current 16/20" suspension EUC.

3) The lightest EUCs today are still 13kg. A KS16x is about as light as a "powerful" EUC can get - the motor is not that heavy, 1500Wh battery gives solid range, no suspension, plastic casing. You can't do that much better.

Your suggested EUC with suspension is going to be much heavier no matter what. Suspension necessitates extra material to hold the pedal hangers and so on independent of the motor (whereas non-sus designs just directly attach the main weight-bearing hangars on the axle and mount the case separately). Something like the new KS16S appears to be about the floor of "decent" suspension EUC weight. I'm sure you could do better, but not by that much.

I think you underestimate the much higher demands on an EUC motor vs an MTB. A mid-drive gets to use a chain reduction to achieve reasonable torque, MTB hub motors are just as heavy as EUC motors and have pretty awful torque thanks to the poor gearing ratio on a 26-29" Rim (unless geared, but geared motors are all gutless because of sacrifices required to fit gearing).

I wish you luck, but you're probably just better off buying a master or something and stripping off all the superfluous parts that protect it from damage, if you really want to get the weight down. Doesn't sound like a great idea for offroad though..

[skunkmonkey]

20 hours ago, Panzer04 said:

I think you underestimate the much higher demands on an EUC motor vs an MTB

Case in point is the low torque inherent in all e-bikes.

[OldSolo]

On 11/18/2023 at 1:38 PM, Vince.Fab said:

If you haven't had the chance to try an Extreme, I think it's what you are looking for as far as ability.  I went from am RST to an Extreme and that brought my trail riding abilities to a whole new level.

I went on a few group rides with a fast E-mtb group on highly technical trails and was able to keep the pace without a problem.  They were very surprised that it could even keep up and we even did the rock garden trails, black diamonds. 

The weight and wheel size wasn't an issue and I've been liking the way the smaller wheels handle strikes and quick repositioning moves.  Long travel is import and it should be progressive.  I've designed a 150mm upgrade for the Extreme to really push boundaries. I also think that's going to be a sweet spot for fast/tech mtb trail riding.  As far as torque goes, imo we are currently traction limited. 

With tire size,  I think you'll want more width.  Tubeless would be nice and running an insert to help mitigate rim damage at lower psi.  A much larger wheel would be interesting if they could get the tq high enough. 

Really looking forward to when VESCs can reach these higher volts reliably.  Being able to tune the motor will be crucial.... that's if you can find the right hardware. 

 

 

I have been following your posts & vids with enthusiasm and was planning to buy an Extreme when you made your links available for others to purchase.  The structural failure that your wheel had (and Begode deciding to push "MAP" making the $2300 purchase a thing of the past) really changed my thinking, so it surprised me to read this post.  Your design work (and fabrication!) is exceptional, are you confident in solving the structural problem in a cost-effective manner?  Begode needs to put you on their payroll, NOT the guy who "designed their suspension" or whatever his consulting was involved in.  Seriously Begode, at least ATTEMPT to HIRE VINCE!!!

 

I will follow you closely with this & look forward to the next entry on your thread.

[RagingGrandpa]

On 11/17/2023 at 11:25 PM, cegli said:

  EUC: MCM5 V2

Every trail is different... where do you ride, and what do you ride? 

From first-hand experience, MCM5 is terrible for MTB  
Low pedal clearance, tight shell clearance. Modern EUC's are a world away from it in terms of singletrack pace. 

[litewave]

12 minutes ago, RagingGrandpa said:

Every trail is different... where do you ride, and what do you ride? 

From first-hand experience, MCM5 is terrible for MTB  
Low pedal clearance, tight shell clearance. Modern EUC's are a world away from it in terms of singletrack pace. 

Yeah, but it's one awesome little wheel for zipping around on sidewalks and in built-up areas. 

[cegli]

1 hour ago, RagingGrandpa said:

Every trail is different... where do you ride, and what do you ride? 

From first-hand experience, MCM5 is terrible for MTB  
Low pedal clearance, tight shell clearance. Modern EUC's are a world away from it in terms of singletrack pace. 

Yep, you're totally right.  I do ride a MCM5 v2 currently.  I got it because it was a cheap/light entry point to see what riding an EUC is like, and something to use to pickup take-out, etc.

I liked it more than I thought I would, and now I ride it on steep rooty, rocky, technical single track with drops, etc.  It's bad at that, but it's all I've got.  I've been waiting for something decent to come along to upgrade, since my budget for EUCs is not large.  I can't afford to keep buying and selling EUCs as they improve, so it makes sense to hold out for something good that will last.

I was hopeful the S22/S22 Pro would potentially hold me over, but I just can't buy something with such a god awful suspension design, plus lack of water resistance and other issues.  The Veteran Lynx looks promising as a stop gap, if the first batches end up being decent.  I won't consider anything with a wheel that's not at least 20", unless they get a lot lighter.

I used to mountain unicycle a good deal, and I've ridden 20"/24"/27.5"/29" and 36" wheels.  A 20" wheel is barely workable on serious trails, but it's at least better than 14"->18"!

[RagingGrandpa]

Try an RS high-torque. They're dirt cheap in the used market now that the suspension hype has taken over. 
Or, T4. More maintenance (linkage-type suspensions always are), but seriously capable, and still dirt cheap used. 

Try a T4 before you "reinvent the wheel"  

Large-diameter tires are great for grip but bad for climbing: I have to dangle over the front end of the MP24 to make it accelerate or climb. It can do it, but I have to work too hard for it. Too big.