AJS & Matchless Owners Club

Here are three of the four different mainshafts fitted to Lightweights. Make sure you get the right one!

just make sure it is the same as yours as there are four different ones 2 for the 250 (old an modified) 2 for the 350 (old and modified)

I have 3 mainshafts that I found this morning - I may have others, but my 'come in handy' store is chaotic. All 3 I measure as 041263. Two of them are in good condition and one has the same scalloping as in the original post.

If needed, I'm happy to loan one of them as a template.

Many thanks keep them safe and i will contact you.

Likewise, if you want to borrow either of my later style shafts (041703/043058), just let me know...

Please note that the Norton lightweights also used these mainshafts with the same part numbers - they might be interested in having some made and might bring the price down.
Also would it be cheaper to have a batch repaired - just a thought

Hi Martin, I faced wear problems on my B52 'box mainshaft which I solved by getting another from Kempton autojumble for a tenner - not much use to you, I know, but I did some research into the matter - all untried but vouched for by others:
Loctite 660 is specifically for loose splines/keyways. However, it is rather s*** or bust as, once set, the bond can only broken by heating to 250deg C, which will probably damage the shaft permanently.
Strips of shim can be slipped between the splines, but the wear pattern on your shaft would make this difficult. You could try short shim slips to fill the worst wear, fixed with retaining compound. Hope this helps, Andy

I have had crankshaft splines welded up and re machined - whether that can be done with a shaft - welding a little at a time?