R45 Racer Project

[DanMay]

Currently I run a R90/6 racebike in the local NZ classic series and have been looking at building a 500 cc bike for another class.

I am running an R50/5 race bike in the 500cc AHRMA class in the United States.  We have done a lot of motor work (cam, valves, pistons, etc.)  The class I ran last year was restricted to stock carburetors, so I was forced to run the Bing 26mm.  This was definitely the restriction point, and we were able to get 32HP at the rear wheel only after enlarging the carburetor bores to about 27mm.  This year I am moving into the “sportsman” class which allows larger carburetors, and I plan on using the 30mm Mikuni.  I think the 32mm Bing will be too large for your application, just my opinion.  We are hoping to get 40HP at the rear wheel this year.

Here are some photos:
https://plus.google.com/photos/114008494495489849005/albums/5953580931462241617?authkey=CKimvbLGle6digE

[Voltaire]

Nice bike Dan, you may be right about the 32mm  carbs but in the class here its no Jap parts.
I had some 30mm Dells a while back but sold them thinking I was not going to bother with a 500 again. Doh.

Latest, spoked wheel arrived from US and Replica SS seat.... taking cylinder to mates to be machined down 3mm.
SS valves, beehive springs and titanium retainers are in too.
Gonna be a busy Xmas.