Just daydreaming (can't always sleep well at night) but I wonder what power a 2CV6 gearbox can cope with if a different engine was mated with it? Just musing about fitting a Honda 1100cc Pan European bike engine to a 2CV gearbox. Would it manage with 100bhp? What would need beefing up, if anything, to allow it to manage? Just an idea (and it gives KH the chance to take the piss);-)

Jeroen Cats reckoned that a 2cv 'box couldn't cope with much more than standard 652cc - and he broke enough to prove that theory...
"- General gearbox caution.
Apart from the previous points, there is another point you have to consider. Will the gearbox you'd like to fit withstand your engine? The normal A-type gearbox will just about cope with a 652 engine. A tuned 652 engine is asking for troubles, the gearbox and clutch simply aren't strong enough. As soon as you start driving hard the gearbox will break."
http://www.cats-citroen.net/citroen_aty ... ml#gearbox

Just for the sake of argument I believe it would be extremely difficult to mate a Pan European motor to a 2cv or any other car box. Although the honda engine is longitudinally mounted in the bike, unlike BMW or Moto Guzzi it does not have a dry clutch and separate gearbox. Instead the gearbox is built into the crankcase and the clutch is in fact at the front. I'm not saying it would be impossible, just very, very difficult.

I had read that before about a 652cc being about as much as a 2cv box can take, the 652, although only slightly more powerful than the 602, is considerably torqueier, and it's torque that kills gearboxes, (as most of you know). Can I conclude therefore that race engines, although a good 10hp more than a 652, are all revs and have no more torque than the standard 652?

Thanks for those replies. I had been thinking along the lines of building a three wheeler, and I know that the Oilhead BMW motorbike engines can and have been mated to the 2CV gearbox, and they must be about 100bhp. I've also read of Pan engines fitted to trikes but perhaps they were rear-wheel-drive and did not use the 2CV gearbox/transmission/suspension?

After a bit of delving, I've discovered that the Pan-engined three wheeler I've seen pictures of was a JZR and (of course) RWD.

At a bike meeting I went to last year I saw a reliant robin with a hayabusa engine fitted. It was awesomely fast in a straight line but didn't go round corners very well The guy had done a very good engineering job in fitting it.