Gearbox numbers.

[reabow gary]

I have the following gearboxes and need to know what models they came from and hopefully the ratios. I am building up a scrambler G80CS and need to use one of these boxes. Can anyone advise?

Gary Reabow.

[orbinrangle]

Your gearboxes didn't follow.

[reabow gary]

My apologies; clearly I did something wrong in typing my query. However the numbers are as follows:
M15267
M35291
M3034
MA18571
MA6823.

Thank you for responding.

regards Gary.

[les ward]

I've sent you a pm. Hope it helps.Edited by - les ward on 26 Nov 2010 7:28:17 PM

[PGGuse]

I own a '64 AJS 500 cc heavyweight single road model 18 imported from South Africa, with AMC gear box No. MA 6767 which is rather close to the last number you mentioned. The gear ratio is definitley for road use.
Hopeithelps.
Paul in Frankfurt

[reabow gary]

quote:
I own a '64 AJS 500 cc heavyweight single road model 18 imported from South Africa, with AMC gear box No. MA 6767 which is rather close to the last number you mentioned. The gear ratio is definitley for road use.
Hopeithelps.
Paul in Frankfurt



Thanks for the response. Now I know that MA relates to road bike singles.

[alanengineer]

If MA stands for road bike single, what does M stand for and is their any interesting features in the number. ie date code?
And what about competition gearboxes?

[les ward]

AMC gearboxes from 1957 are stamped M for Matchless/AJS and N for Norton, as the outer cases differed. Competition boxes that I have seen have sometimes been stamped S and T, presumably for Scrambles and Trials. I have also seen R on some later boxes, but it isn't short for "Race" as they are from road bikes. From the early 1960s the designation goes to MA for Matchless and NA for Norton. G15 machines can have either NA or MA. Later P11s have the same number on frame, engine and gearbox. None have a date code.

[Rob Harknett]

Les, I made an Excel file of about 35 numbers I discovered everything you state. All are prefixed with M up to 1962. Some have T, S or R suffix. I thought R was for CSR as the bike that had an R suffix was a CSR. Comp bikes seem to have low numbers. It can be seen in the file sorted by numbers, AJS & Matchless shared the numbers. The year of most bikes fall in numerical order of the gearbox number. Most bikes have probable been restored.
Bike gearbox numbers that do not fall in numerical order, must be fitted with a wrong year gearbox.

[ajscomboman]

M denotes an early type kick start lever return spring that pushes into the inner case drilled hole, an MA is a box from 1962 on with the later hook type kickstart lever return spring and the later type inner case with a boss to suit the hook. Has no bearing on the gearing fitted.