reliant trike gearbox issues

[Teaby]

I am currently having my first build to clear my garage,

Anyway I have a old GS500 frame I am considering strapping my reliant engine and rear axle onto.

In my mind I want a short arse trike, one seater.

Anyway my question is do I need to use the gearbox, or can I use a drive shaft between the clutch and rear axle, so I will just have one gear.

Can anybody give me any guidance towards any pitfalls I may encounter during the build or out on the road

Any help will be appreciated

Thanks in advance

[Blackjack]

Depends.

If you have an early axle with the low ratio, and the wheels you use aren't too tall, you don't build it out of 1/2" steel plate, and you're not overly fond of pies, then perhaps.

Use a tall axle ratio, tall wheels, build it out of RSJs, and eat too many pies. not a chance in hell.

All that would depend on just how asthmatic the engine you have is too.

[johnr]

why? reliant engine is hardly enormous, and the gearbox is no monster either. why not bolt the output shaft of the box directly onto the axle with just a uj to make the joint. aside from having to slip the clutch everywhere to make progress, (the reliant really needs all of its gears, remember, at best we are talking 35-40bhp from an 850) you will need to make an adaptor plate to bolt to the back of the engine, as the clutch curently operates fron a lifter in the bellhousing of the gearbox you want to bin, so, you will need a clutch lifter, and a propshaft that has splines on the end to allow you to operate the clutch. aside from that, im not too sure what the msva/mot man would make of a vehicle that couldnt be left ticking over without having someone sat on it holding the clutch down. i cant help but ask the question why?
imho, youre wasting your time. last reliant trike i built was a shortarsed thing, but i still used the reliant box, mine used a z650 frame. you really wont need to build it without a gearbox in order to make it short. i recon a reliant engine and boxtogether wont be much over 4 feet long. thats probably not much more than a big bike engine and swingarm.

[Teaby]

Cheers I spoke to mate this afternoon who shock his head too Many thanks Lads