Hey thanks for that buddy. I possess a BMW R1100GS so know of shaft drive rears. Wouldn't use one of those because shafts are more draggy. The offset is very different from the Honda VFR too. BMW 800 twins etc. are all single sided swinging arm with a big belt drive.
I'm into 14" rims all round which will preclude the vfr's rolling gear I'm afraid.. but its a good call!
Belt drives. Are they expensive? Cedric Lynch uses a 20mm belt at I think around 3.5:1 which seems very cheap indeed, around £8 to replace. The torque of our motors are higher than the "ice" equivalent but suitably set at the controller, tend not to deliver shock loads.
Here's some 8mm pitch belts:http://www.bearingboys.co.uk/8m_Section ... ch_-1222-c
And some suitable pulleys:http://www.bearingboys.co.uk/8M_Section ... mm_-1804-c
Remember, these don't wear down so you can spend a little more. The belts don't make horrible noises nor require constant maintenance.
On the down side of things the EU are expanding their strangle hold on our freedoms with a raft of new laws. Trikes used to be a no-mans land of type approval. We have to get our fingers out. The MAG (Motorcycle action Group) have held a huge protest about these bigotted, lies of a bill. MEP's have joined in the cause but the political hierarchy are the EU's butt boys and guard dogs. It's going to be tough.http://www.dft.gov.uk/consultations/dft-2011-26
And the actual d(r)aft set of proposals:http://www.dft.gov.uk/consultations/dft-2011-26