Two Wheel Drive

[Generali]

We have four wheel drive cars for driving off road (and through Chelsea). Why don't we have (m)any two wheel drive trail bikes?

[DrFfybes]

Mainly Steering.

The complex hinge arrangements required to take drive up to the headstock and down the dorks, or along a front swingarm arrangement, are too expensive to be practical.

Then you have extra weight, which is a major factor on something nominally 100-140kg.

Paul

[gryffron]

I can't believe cost is the major issue. Somebody would pay for it, if it helped.

I'd say partly weight. And more especially weight distribution. There's very little weight on the front wheel of a motorbike, so even if it was powered it wouldn't add much to the grip. So lots of extra weight to achieve FWD, for very little benefit.


(Edit: No weight at all on the front wheel of a track bike. Just watch and they are practically lifting the front wheel all the time they are accelerating. I think it would have to be VERY wet, we're talking monsoon, to get 5s/lap advantage.)

gryff

[quelquod]

(Edit: No weight at all on the front wheel of a track bike...

I'm not so sure - all of the bikes that I've owned (even my old Goldie and Manx) had a fairly even weight distribution statically when you were astride and I think there would be a good gain on cornering (much of the time in bike racing) where it's difficult to use too much of the available power. 5 seconds does sound very optimistic though- maybe in the snow .

[redsturgeon]

I used to do quite a bit of off road motorcycling and I cant think that having a driven front wheel would be much use in most situations. It was very rare to get stuck through lack of traction and the added complexity would just not be worthwhile for those few times.

John

[gryffron]

Interesting to note there have been quite a few 2WD concept bikes. And even a couple that made it into production.

http://www.visordown.com/motorcycle-top ... otorcycles

The idea of a hybrid with motor assisted front wheel is clever. Gets round all the nasty transmission problems. And can be computer controlled to avoid wheelspin.

[DrFfybes]

The idea of a hybrid with motor assisted front wheel is clever. Gets round all the nasty transmission problems. And can be computer controlled to avoid wheelspin.

Now an electric motor powered front wheel does sound like a solution. Of course you would have to have VERY good traction control - any sort of understeer on a bike is a Bad Thing.

Paul

[robbelg]

These people make them - and have for some time

https://www.rokon.com/

[MonsterMork]

all of the bikes that I've owned ...... Goldie and Manx .......

You can go right off some people

[Generali]

Thanks all, some fascinating answers.