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marc

Why not EUCs with wider tires for higher torques?

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EUCs  with bigger wheel exists like 22" EUC while it does not increase stability in comparison with a 18" (am I correct?), but I think there is more need for EUCs with wider tires for better tire-road adherence and for higher torques. It increases safety because you can brake faster. It can give more acceleration without slipping and higher bending angles at startup.

Last time I fell down at zero speed because I asked too much torque (bending too much) however I am only 65kg. At standstill I bowed too much forward, that I fell forward (with helmet). Since it is the most powerful EUC of the world, I had confidence on it but I had to limit my confidence. apparently 1kW nominal power and 3kW max. power (gotway msuper v2) is not enough sometimes, even for somebody of 65kg. 

Maybe no wider wheels are planned to produce for EUCs because of motor power limitations to 3kW max power. Is that the reason for motor power limitations?  (on the other side, to be honest, riding at 30km/h on a steep hill of 30degrees, is in fact good enough as EUC power)

Do somebody know if a EUC exists with a 18x4 tire? I have a 18x2.5 now. gotway msuper.

X001-Y001.jpg

Edited by marc
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Those are super knobby tires so although they might give you grip in offroad conditions they're not at all ideal for smooth city riding on streets or sidewalks. The new Ninebot One Z has a much wider tire with a relatively smooth tread, it might be what you're looking for. Really though, EUCs are not like two-wheeled devices where you can accelerate faster than the friction on the tire. Minimizing rolling resistance helps battery life. Also I wonder about the effect of a larger heavier tire/wheel on battery life, since the motor then needs to move more mass in order to maintain balance. 

 

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8 hours ago, LanghamP said:

I think there's a lot of merit to having a wider low pressure tire even at the cost of power usage

My legs, quads, and knees agree with you. :D

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why would a wide low pressure tyre be better for comfort than a thin low pressure tyre?

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22 hours ago, marc said:

[...] I think there is more need for EUCs with wider tires for better tire-road adherence and for higher torques. It increases safety because you can brake faster. It can give more acceleration without slipping and higher bending angles at startup.

Missing torque due to lack of tire grip is AFAICS not a relevant limitation for EUCs. Wider tires in themselves don't give significantly more torque anyways. A "softer" rubber is the main reason why wider tires may provide more torque.

22 hours ago, marc said:

Last time I fell down at zero speed because I asked too much torque (bending too much) however I am only 65kg. At standstill I bowed too much forward, that I fell forward (with helmet).

Do somebody know if a EUC exists with a 18x4 tire? I have a 18x2.5 now. gotway msuper.

Unless your tire span out you problem was not tire grip. I have had spin outs on mud, snow, or grass, but in none of these cases a wider tire would have changed the lack of grip on the surface. The Ninebot Z has and 18" 4.1 wide tire.

4 hours ago, exoplanet said:

why would a wide low pressure tyre be better for comfort than a thin low pressure tyre?

Most probably you can't run a thin tire on that low pressure you can run a thicker tire. Or in other words, there are no thin low pressure tires.

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1 hour ago, Mono said:

Most probably you can't run a thin tire on that low pressure you can run a thicker tire. Or in other words, there are no thin low pressure tires.

You can have a high pressure narrow tire but not a low pressure wide tire because the <deformed> contact patch's size must equal the the PSI times the total weight of the EUC and the rider.

For example, if you and the EUC weight 200 pounds, and you have the tire pressure set to 50 PSI, then the contact patch is four square inches. If you have a narrow tire, then those required square inches will horribly deform the tire, possibly coming off its rim. In addition, the more flex you introduce the more heat you have, and beyond a certain amount of flex the tire will get damaged. Tires do particularly bad when underinflated.

Wider tires can be flexed more to give you those four square inches, and will not be deformed much. In addition, wider tires can go to radial sidewalls whereby the sidewall does much of the deformation to give you those four square inches. Narrow bicycle tires with flexible sidewalls aren't popular because they give a disconcerting feel, and so we see super-narrow tires with insanely high PSI, like on the order of 120 PSI.

Wider tires, of low pressure and of radial construction, give so many benefits over narrow bicycle tires we presently have that I see all EUCs moving entirely to them. You pedal a bicycle and so you need narrow bias-ply tires to minimize that side to side motion, but you ride an EUC, and so like scooters and motorcycles a reasonably wide tire gives the best comfort and handling.

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However the varying circumference at different points of the tyre make you slow down in turns etc. tilt. Narrower tread gives better handling at least on flat surfaces.

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11 hours ago, exoplanet said:

why would a wide low pressure tyre be better for comfort than a thin low pressure tyre?

 

3 hours ago, exoplanet said:

However the varying circumference at different points of the tyre make you slow down in turns etc. tilt. Narrower tread gives better handling at least on flat surfaces.

Science not your strong suit then is it 😜

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@Smoother will soon be making a project on 2 KS wheels, maybe we can get some feedback about wider tires in the coming weeks when the project is done. It's mot a much wider tire (2.25-2.5) but the tread pattern on the tire is different than the standard provided with KS and more like the ninebot Z tread pattern

 

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comfort comes with a bigger wheel (as the tangent to which it hits an un-even level is smaller) while a wider tire with harder walls and lower air pressure acts as a suspension. A wider tire might also touch various parts of the road so the average pressure to the ground fluctuates more smoothly in the long run, unlike a hard high-pressure narrow tire. Never the less the higher the pressure (and not exceeding the requirement based on the load) will probably make the unicycle more solid to ground than a low pressured one.

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On 2/7/2018 at 1:35 PM, Mono said:

Unless your tire span out you problem was not tire grip. I have had spin outs on mud, snow, or grass, but in none of these cases a wider tire would have changed the lack of grip on the surface. The Ninebot Z has and 18" 4.1 wide tire.

My tire did not span out but the torque was insufficient to compensate my forward bowing to keep my at stand up position, however it is a 3kW Gotway Msuper. EUC reached max. torque and kept on this torque, it did not cut off but I was bowing too much forward, asking too much torque. I think if wider tires could be used maybe the motor power could also be increased

Edited by marc

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I put a Larger knobby on my Monster but it made it harder to make a tight turn and made it slightly harder to balance.

I put up a thread in the Mods section about it: http://forum.electricunicycle.org/topic/8705-tested-gotway-monster-with-upgraded-knobby-tire/

I recently returned my Monster to it's original tire for more control.

 

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