I've been thinking about a reliable, light, cheap, & non power sapping reversing mechanism for my Caterham (de dion chassis, Hayabusa motor).

Whilst chatting this over with a mate, we came up with the idea of using an over-running clutch. This would run free when the car was being powered forward by the engine but when drive was applied to it, it would reverse the car.

The plan is to mount the over-running clutch to the chassis somehow so it can act as a central prop shaft bearing. I'd use a bike starter motor(about 0.5kg) to power a gear running round the outside of clutch.

I've done a really poor sketch of what I'm planning and I'd appreciate any comments (sketch is in my photos - bec drive train).

If someone's thought of this before, which I expect is the case, and not used it I'd like to know why. There appears to be some very nice clutches available at a reasonable price so I think the clutch itself will be available.

I would have to source one that would cope with the engine torque, the revs, the hostile environment, the lateral forces of operating as a central bearing, but if I can get one to suit, what else should I consider?

I would leave the prop as it is and mount the overrunning clutch/motor on the diff flange.
I think that a "half way" bearing causes more problems than help on the propshaft,all IMHO though....very humble

I've only heard of them as sprag clutches for industrial machinery like conveyor belts or in automatic transmission. Have you got a link to one?

[Edited on 21/11/04 by Peteff]

If you think it through it wont work, as the as the clutch will be running the wrong way. Sorry

I still think the best way is push it

peteff: Indeed - sprag clutch probably due to high revs. http://www.warnernet.com has a range of clutches and reckon they've got something that will suit anything - I'll give them a call tomorrow. If you want to see their catalogue you have to register - a pain, but they have a lot of stuff to oggle.

Cita: Diff flange would be the ideal place but a Caterham has next to no space in this area..

Mk-Ninja: Hmmmmm <thinking it through>.....nope, pretty sure it will work.

Dean: I need a reverse for motorsport, otherwise I wouldn't bother.

We've already had this conversation in here I'm afraid...
The very thing that makes it be an over-run clutch is precisely what will make it not work for a reverse.
If you manage to thank of a way around this, I'd be keen on hearing about it

zilspeed: I've searched for the previous conversation but can't find it. Do you know where it was?
TIA !

Hi

Do a search under sprag clutch.

It doesn't detail it very much though.