Sleeve gear slip

I am currently overhauling my Mk3 gearbox. I put new bushings in my sleeve gear and pushed the main shaft into it by hand with slight resistance finishing it through with a rubber hammer. I then proceeded to install the rest of the layshaft/mainshaft gears rotating the main shaft with every new gear to check for bind. Finally temporarily installed the inner/outer covers so I could manually shift through all the gears and I couldn't get it into fourth due to the sleeve/fourth gear on the mainshaft slipped so the dogs where in line with the dogs on the third gear not allowing the forks to push 3rd gear dogs into the forth gear dogs. So I removed all the gears and twisted the mainshaft in the sleeve gear so the dogs would fit with the third gear dogs again. My question is should the sleeve gear slip like that on the main shaft or will tightening up the nuts on both ends of the mainshaft keep it tight and not allow for it to slip. oh yeah I am new to the forum and to nortons I purchased two Nortons last spring a mk2 and mk3 as a package deal and I'm looking forward to getting them both road ready both are in need of a lot of work so I will be using this forum as a learning resource. Thank you, Kevin

The sleeve gear has to rotate freely on the mainshaft in the first 3 gears, it only gets locked to the mainshaft in 4th when the sliding gear engages with it. You should not need to hammer the mainshaft through the sleeve gear, the bushes need reaming to give the clearance specified in the manual which will be something like a 1.5 thou clearance.

When testing the gearbox for gear changes you will need to rotate the gearbox sprocket to turn the sleeve gear, in any fixed position you never have all the dogs lined up so the gears need to be rotating for the sliding gears dogs to find the proper holes in the adjacent gear.

Thanks that makes me feel better about it. I didn't have to hammer I just tapped the shaft lightly to get it the last few inches. I probably could've pushed it all the way by hand but it was a snug fit. Thanks for your response.

still sounds too tight to me. it should be an EASY hand fit and spin freely in the sleeve gear.

KevinS said:

I didn't have to hammer I just tapped the shaft lightly to get it the last few inches. I probably could've pushed it all the way by hand but it was a snug fit. Thanks for your response.

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Bill +1 a snug fit will create heat and the shaft will bind in the bushes.