BSA Owners' Club Forum

The BSA Workshop => Twins => Topic started by: reedspeed on 16 April, 2017, 20:58:43

Title: A65 Thunderbolt 5 speed conversion
Post by: reedspeed on 16 April, 2017, 20:58:43
I have a 1969 650 Thunderbolt. The bike badly needs a 5 speed transmission to enable it to be run on the Interstate highways here in Florida. What are my options?

Jim,
Vero Beacg, FL
Title: Re: A65 Thunderbolt 5 speed conversion
Post by: STAR TWIN on 17 April, 2017, 10:00:33
What exactly is the problem? Is it undergeared for Highway use? If so, a gearbox sprocket with an extra tooth or two would solve the problem.
5 speed boxes (expensive!) generally don't affect top and bottom gear ratios - they just make the jump between ratios smaller.