Super Rocket rear fender fitment

[cal223]

I appreciate the information I'm getting here.
The gearbox is standard.
Oh, the many layered onion that is the unrestored classic bike.
Trev, what size tire do you have on the rear?  I'm currently running a 3.50X19, K70 type but I prefer the K81.

[trevinoz]

Cal, I have an Avon Roadrunner, 4.10H19 on the '62 Rocket. 3.60 19 K81 on the front. I would have put a K81 on the rear but the Avon was here. Those sizes are supposed to be equivalent to the 3.50 & 3.25 sizes.
I usually use K81s on the Rockets and K70s on the Flashes or the Chin Shen clones.
I'm surprised you have a standard box on your rocket as I thought mostly they had STD2 or STB2 [same thing] boxes in USA.
Trev.

[cal223]

My mistake, I was going from memory there with the gearbox.  It is an STD2.

[trevinoz]

I don't know what BSA were thinking when they lashed up the STD2 box. Apparently it's a mix of scramble gears and road gears. Extremely low first gear, good for wheel stands and quick starts. A friend had one new in 1962 and reckons the box was only any good when he had a sidecar on the bike for a while. He ended up changing to STD ratios.
    Trev.