Paul,
Other than Tracy's PSRU what options do I have?? Do you have a preference and why??
At this stage interested in a muffler, but will confirm.

Neil Unger.

Not many options for PSRU's.

I was in a motorcycle shop buying parts for our Ninja motorcycle
and I noticed the forged aluminum rear cog belt sprocket on a lot
of V twin Harley motor cycle copies. That may make a good part
for a belt reduction drive. You might need two side by side.
Ken Welter uses a 3:1 belt reduction drive on his Coot.

Paul Lamar

                       
As far as PSRU's go for Cog belt, I think the northwest aero pulleys were and are the best. Light weight, anodized and  built for really high horspower.  I have two sets I cannot use, ( I am doing a vebelt drive for reasons of vibration damping).  If your are interested I can supply pix, data.  They are 2.17 to 1, which may not work for you, and they are built for 400 horsepower, but they can be cut down very easily.  They use gates belts.

On another note , Paul are you against gear drives since you mention harley clone belt drives on motorcycles ?

Lionel

No but Neil is in Australia which might make one of Tracy's drives very expensive.
The belt drive is an alternative. I prefer gear drives. The draw back to
belt drives is they are rather bulky in the 3:1 range. A very large
pulley is required.

Paul Lamar