I have a gearbox shell for late rigid model to use for my 1953 T100. I have a few sets of inner and outer cover But I can't figure out how to select the collect inner and outer covers for my 1953.
I looked up the parts number in the parts manual and figured out that I need T931 for inner and T935 for outer. So I checked the casting number of the covers I have right now. The casting numbers are all T411 for inner covers and T932 and T1219 for outer covers. I looked up T411, T932 and T1219 in the 50 to 57 parts manual but I can't find any of them in the manual. So I have no idea what year and what model they are for. Does anybody know?
Is the casting number different from the parts number in the parts manual? If so, how should I distinguish the year of the covers?
G'day. As far as I know the late (post 1950) rigid gearboxes used a lot of parts common with the swinging arm gearboxes. If the main gearbox case has 3 screw points (1/4 whit) running along the bottom of the casting then any pre unit middle/outer casting will fit. Some of the casting marks may not be matching but everything will still work. Dont get fussy with casting numbers.
1950 Speed Twin outfit 1951 Thunderbird outfit (76 degree racebike, or is it 90 deg now?) 1955 BSA D3 minibike outfit Triumph solo's
Mac - Mr 76 is correct, the 2 outer covers were shared with later swing-arm models up to the introduction of the slick-shift. What will be most important for you will be matching the look of the oil fill hole. I believe there were several tiny changes. Also, one model may have anchored the clutch cable to the steel g/b adjuster and another had it cast into the inner cover... but maybe I've been staring at A10's too long.
The big thing is to NOT go by the cast-in part numbers. One number was used for the base casting or forging. And another number was used for the finished machined part. So 2 or 3 different finished parts could come from a single casting or forging. So you can get into trouble using the number you see on the part itself.
I am surprised at your comment!! I checked my inner covers just now and found that your are correct! The one of my cover is surely straight up and the other one leans out a few degrees. I didn't know the differences!!