Norton V Triumph?

crikey where does one start? I am a gearbox virgin I have the same knowledge of them as I do of that wizardry and black art electricary however

I have a T120r 1961, I rebuilt this from a running wreck, I replaced all worn parts in the gearbox I found that all Triumph gearboxes were similar and very nearly all parts were the same, I'm including bearings in this, the damn thing although nice to use, gearbox that is not the bike, still crunches when put into first! doesn'r matter what you do before hand still does it,

My G80cs bitsa had a Burman box and a short stroke engine so had to run an amc [norton] clutch that was fun sorting a chain line and retention of the basket out not a bad box but quite slow

Eventually I fitted an AMC box which I believe is actually a Norton gearbox, it is in my view a damn good box, had to refurbish it a bit and the only criticism I have is the price of a new kickstart shaft. it will have to wait and that silly l little gear lever return hairspring which seeems to be so weak it breaks real easily,

If you bear in mind , these boxes are of ancient prewar design, I believe the AMC/Norton box originated from a Sturmey Archer design then they ain't doing to bad.

Did you refurbish the Triumph box before reinstalling it in the rebuilt bike?

kind regards

still crunches when put into first! doesn'r matter what you do before hand still does it,

That is a clutch problem, on my TR6 I got rid of this behaviour by spending time on the clutch, the lifting of the pressure plate has to be perpendicular to the rod so the clutch has no drag, that's after checking the clutch plates for wear and grooves in the clutch body. That plus a low tickover speed should fix it.

Yes it is a clutch problem. I fitted an LP Williams 7 plate clutch to my TR6 which suffered from the same problem. Wow what a difference and selecting neutral at a standstill is easy.

The AMC box as fitted to Norton,Matchless ,AJS etc from the late 1950's has a good reputation for light action and reliability, and copes well with power outputs up to 50 bhp. It can suffer the same problems as TRiumph boxes and some issues can be hard to spot. After years of putting up with a poor action I have found that contact between the back of the clutch center and sleeve gear shoulder was the cause , a few seconds work with the bench grinder and WOW what a difference. Another issue is with pattern clutch plates that have insufficient clearance to the drum.

yes I would agree it's a clutch problem, however when I rebuilt the machine many years ago I replaced the whole of the clutch with a new 3 spring one for the later Triumph and BSA's, see what I can do with it should I ever use it again, kind regards