Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[princec]

Wide tyres = softer rubber able to cope with torque. They don't offer more grip just because they're wide, it's because they can make the rubber softer and not get torn to shreds.

From a handling perspective, you want the narrowest tyres possible, with the absolute lightest unsprung weight you can get away with. 1kg off a wheel is worth 10kg off of anywhere else.

From a cost perspective you want the cheapest thing that does the job of a wheel, and funnily enough for the last 10000 years nobody has yet come up with a better way to do it than an axle in a hub, because that really is the best way to make a wheel. Rim drive has popped up now and again several times before, and ... disappeared without trace. I see a pattern.

Cas

[Crissa]

It has advantages that require lots of precision to solve.  Which we have now.  Spacing out the magnets makes the pulse pattern much more efficient.

There'll always be a balance between, is the materials and precision going to cost more than the parts to balance it out?  Maybe today is the day that answer is 'no'.

-Crissa

[gregj]

Princec.
" Wide tyres = softer rubber able to cope with torque. They don't offer more grip just because they're wide, it's because they can make the rubber softer and not get torn to shreds.

From a handling perspective, you want the narrowest tyres possible, with the absolute lightest unsprung weight you can get away with. 1kg off a wheel is worth 10kg off of anywhere else."

This is basically a completely incorrect statement.
The size of the contact patch is optimal for a tyre and motorcycle system. If the contact patch gets too big the pressure at the patch is less and there is less grip, and if too small the pressure is too high and the rubber will be overstressed and break grip.
 Motorcycle lean, so the contact patch travels all over the tyre this helps keep the compound cooler and distribute the wear.
A larger tyre also is PART of the suspension. It does most of the micro vertical travel. The larger the tyre the more the tyre can deform to take up road surface variability. This is particularly important when leaned over and the suspension travel is effectively less compliant ( cos of included angle).
Narrower tyres are actually better for straight line speed ( for a number of reasons), not just areodynamics. See speed record attempts.
The big problem with going too wide or too narrow is the SHAPE and position of the contact patch .

You are correct about the importance of unsprung weight though, which is why hub motors on motorcycles are not such a great idea. The wheel weight relative to total system weight is much higher than most powered vehicles, so is extremely important to dynamic handling.

BTW wider does not necessarily mean lighter. On one of my smaller racing motorcycles I had a problem getting a tyre. I  needed a 150/60 but could only get a 130/80. The 130/80 was 2kg heavier than the 150/60! Needless to say it didn't stay on long...

And yes wheel/hub has huge benefits over everything else so far. But never underestimate the innovation potential of humans.

[Richard230]

Don't forget that a wider tire is seen by many motorcycle customers as providing superior handling and traction - because that is what they see on race bikes.  However, that can end up with a tire that is a bit too wide for the job, but was selected by the marketing team as something that will improve sales. 

[princec]

Uh, it is not any way an incorrect statement but I'm not going to argue about it in here.
<edit>Actually no I realise that this will just end up in a stupid forum argument so here's a link to divert everyone's attention: https://www.physlink.com/education/askexperts/ae200.cfm
Yes I know it's about car tyres but the basic gist of it is exactly the same.

Cas

[Crissa]

Yes, you got into a stupid forum argument because there is a too wide and a too narrow.

-Crissa

[princec]

I ... don't recall an argument about too wide or narrow?

Cas

[MVetter]

Main issue: motorcycles in the US are legally required, according to my sources, to have an actual rear brake. Not just regen. Disc or drum.

[DonTom]

Main issue: motorcycles in the US are legally required, according to my sources, to have an actual rear brake. Not just regen. Disc or drum.

And I think I also heard the brakes have to be more powerful than the engine / motor. IOW, the brakes will slow down the vehicle even if stuck at WOT.

-Don-  Reno, NV

[Richard230]

Check out the exploded diagram of the Verge electric motorcycle's rear wheel/electric motor on their website:   Very interesting, but I wonder how heavy it is, how will it affect handling and ride comfort and what will it be like to change the rear tire? And I bet it costs a bundle to manufacture and from all unique components, too.  https://www.vergemotorcycles.com/us/

[DonTom]

Check out the exploded diagram of the Verge electric motorcycle's rear wheel/electric motor on their website:   Very interesting, but I wonder how heavy it is, how will it affect handling and ride comfort and what will it be like to change the rear tire? And I bet it costs a bundle to manufacture and from all unique components, too.  https://www.vergemotorcycles.com/us/

When they say "With the 20.2 kW battery"  do they mean 20.2 KWH?" Any real specs on the thing?


I hope that rear direct drive proves to be reliable. I like the idea of no belt, chain or shaft but not so much of a new design that doesn't have many hundreds of thousands of miles of road testing.


I also like the weird looks.




-Don-  Auburn, CA

[Fran K]

Here is a screen shot of the motor so you don't have to decide whether to accept their cookies or continue without consent.

I want to see what is essentially the wheel bearings.  I put some yellow next to the attachment point to the swing arm?

[TheRan]

The ring next to the brake disc will be the bearing. I wonder if it's some off the shelf component or custom.

[Richard230]

Verge has announced another new model, the 2023 Verge TS Ultra, with very impressive specifications and a price to match:
https://thepack.news/verge-motorcycles-introduces-it-3rd-model-verge-ts-ultra-at-ces-2023/

[Fred]

I'm looking forward to these being available for a test ride. I've ridden a prototype a few months ago so I know it's not vapourware, but I wasn't able to give it a proper test to see if their claims are realistic.