G: Gearbox (Other - Albion, AMC, Norton etc.) Norton Box: Q- Final Drive Ratio's Comet?

[Jez Nemeth]

Followed your advice on that one Chris on the 'Comet Primary Q's?' thread, and it's really lovely -thought it was going to be harsh, but really not -couple of mm's of synth rubber makes all the difference, and the E10 belt stronger than the chain by a margin -best bang for buck I've spent in a long while, and for less than the price of a new Mumbai petrol tank without shipping. The Ratio is good too -Primary makes little to no sound, all exhaust, tappets and drive chain.

There are other issues though, namely ejection of oil from gearbox, it's at an unnatural angle, and has a tendency to throw out oil, Breather mainly, and I suspect it's getting around the nxnot down the shaft to the Clutch (there's a seal on the clutch nut to stop that) Added grease/oil -as used in the Burman's -seemed to be better.

Its either that, or I have too much in there, or the angle is an issue. Want all gears at least dipping into the stuff. To my reckoning as its not getting the power of a Commando/Atlas, so should be fine.

 

[Chris Launders]

If there is room, epoxy a suitable sized Dowty seal on the end of the sleeve gear, I found some that were small enough OD to still get the sprocket off, I also know of someone who used a 2nd sprocket nut with a housing he made to take a proper oil seal that ran on the mainshaft, but there are several lengths of sleeve gear/threads and it depends what is fitted in yours.
I have used a sealed output bearing in all my Norton boxes as well.
The only breather should be a tiny hole in the inspection cover.
There should be enough in to near the top of the K/S shaft when you look through the inspection cover. You could also change to a semi fluid grease as the earlier boxes use, 00 grade is what I have in my Dollshead and Sturmey Archer boxes.

 

[vibrac]

I fited a belt drive on my Grey flash with a mainshaft oil seal and a Newby clutch on a Albion Box. After a couple of years the primary case is still dry

 

[roger v]

Coming from a Velo background and now preparing myself for a Norvin project , the Velo Venom four speed box has a huge step from second to third ,so the Quaife five speed item really improves matters . Now does the same apply to a twin set up for road use only , is there any advantage in five speeds

 

[Chris Launders]

I have a Quaife 5 speed cluster I'm going to put in a Norton box to try in my Norvin to see if it makes it more town friendly, my standard twin is fine with it's 4 gears but the Norvin's higher gearing, MK2 cams and 34mm carbs means it doesn't pull well at low revs and the Goldie's a bit anti-social if you rev it, going to fit a straight through absorption Vincent silencer first though.

 

[Mike 40M]

The oil/grease mix works fine in the Burman box, preventing most of the leaks. But a Norton box don't need the grease. The AMC box rarely leaks. Nowadays there are GL-5 oils that are yellow metal friendly. The Velocette belt drive kit previously came with a 90 degree recommendation but now has an exact centre to centre measurement. Anyway the 90 degrees twist works fairly well.
Edit: It looks like you have a Commando box, with a different breather hole than the earlier ones.

 

[Jez Nemeth]

It's leaking drive side, sleeve gear pretty sure as Chris pointed out, does needs a seal there mefinks which it will get in the Winter strip down/build up -when I bought it originally, had a breather hole in the inspection cover, indicating the earlier type box? When I put the Vincent screw on inspection cover, thought it should have a breather, didn't put one in the expensive cap but a 2mm next to where I moved the clutch cable entry point -been coming out of there a bit, but think that's levels. Moved to grease Mike just to see if it would cure the leakage, nope. Live and learn!

Aiming for a drip free experience -fair way from that presently...

 

[erik]

The reason for a leaking driveside is the spacer behind the sprocket.This spacer is not hard and starts to creep under the pressure of the sprocket nut.The result is a digged in seal and a loose sprocket with then wearing splines of the shaft.To cure this i recommend a spacer of a hard material! Erik