AMC Gearbox level

skipsoldbikes said:
I have heard of guys running a dry primary & just lubricating the chain with chain lube, seems to me that like the bearings wouldn't last very long.

If you don't make a habit of stopping in gear with the clutch pulled, but ALWAYS go into neutral when standing, the clutch doesn't actually get used much. ?
Not that that is any substitute for the clutch bearing being lubed...

Its a bit rougher on the gearbox, and they probably won't last as long, but its also perfectly possible to ride (almost) without ever using the clutch.
Race guys on Nortons often don't touch the clutch in a race, they say it just promotes the chances of it slipping.
If you practice this and get the revs right each time, it produces quite a smooth riding style.
Even bikes with tractor gearboxes can do this.....
 
Ahhgg, got the clutch adjusted as per manual, put the primary cover back on and now when I pull the clutch lever in, the clutch hits the inside of the primary cover and pushes it away from its seal!!
What the hell is going on in there? There is no clearance at all in there for the clutch to disengage.....it seems to be centred in the bulge in the cover but there is no room,
Has anyone had this happen?
This is a 650ss by the way
 
Have you looked inside, to see which part of the clutch is touching the outer cover ?
If the 3 bolts used are not the correct ones, or have big heads, they can touch, there is not a lot of room to spare in there.
Or, if the primary cases are not correctly spaced out from the engine/gearbox enough, this could happen too.
Is your clutch standard, with the correct number of plates, and thicknesses ?

I don't have a 650SS, so can't precisely say exact spacings.
But those marks on the inside of the outer cover are common on many models of Nortons over the years !
 
Thanks Rohan, I took off cover, looked inside and it was hitting right in the centre, so the slotted adjusting nut was hitting. I checked the clearance again and it was right (half a turn out) so I removed it and took the clutch rod out, and it's mangled beyond recognition on the actuator end. I don't know how but the clutch rod was too long by a quarter inch, there's just no way it could fit between the actuator and the primary cover on the other side.
It must have been like this for a long time, cause the guy I bought it off said it had the worst clutch he ever felt. So I cut a quarter inch off it and cleaned it up, put it back in and the adjuster doesn't stick out anymore and it has very nice action on the lever. It doesn't lift the primary cover now either.
He also said he could never get it to hold primary oil and I now know why.

I'm using ATF in the primary and it comes out as fast as I pour it in, it's got a new seal too, so I think the cover must be damaged.
 
If you have the pressed steel chain case they were notorious for their oil leaks.
The Norton clutch is one of the smoothest on the planet, if you assemble it correctly and use the right parts.
If you are talking about the pressed steel case, the outer can be easily warped by over tightening the chain case nut, which was common as owners tried to stop the leaks.
First check the chain case mounting bracket at the clutch end as any misalightment meant the clutch hit it when used. If the worse came to the worse, space it out on both the front Crank & clutch end, with a washer(s).
The rubber seal should not have any steps in it whatsoever, and if it has it may be possible to restore it by immersing it in hot water. Otherwise a new seal is on the cards.
Use copious amount of oil resistant plastic sealant on the inside and outside of the rubber seal to about halfway up, then leave for at least 72 hours in a cold climate for it to set before pouring oil into the chain case.
HTH.

P.S. also suggest that you check if your clutch lever is the right one, for smooth action, it should be 7/8 inch between the centre of the nipple and the centre of the clutch pivot
 
Bernhard, my clutch lever is 1 1/16" between the centre of the pivot bolt and the centre of the cable end, not 7/8". It's one I just bought off eBay.
Could this make it hard to pull in? It feels good and smooth now and works perfectly but it's a little hard to pull in. I just thought it must be a Norton thing to have a heavy clutch lever.
Do I need a 7/8" between centres lever?
I want to get it right before I take your advice and seal this chain cover shut.
 
TBolt said:
Bernhard, my clutch lever is 1 1/16" between the centre of the pivot bolt and the centre of the cable end, not 7/8". It's one I just bought off eBay.
Could this make it hard to pull in? It feels good and smooth now and works perfectly but it's a little hard to pull in. I just thought it must be a Norton thing to have a heavy clutch lever.
Do I need a 7/8" between centres lever?
I want to get it right before I take your advice and seal this chain cover shut.


Re; “Could this make it hard to pull in?”

In one word-YES!

The gearbox end is also 7/8 inch hence the warning.
 
Thanks Bernhard, looks like I'll have to put the old rusty one back on for now, I checked it and its 7/8"
 
Something else to consider when installing the rubber band seal on the tin primarys, if you measure the cross section of the seal, you will find one edge is slightly thinner than the other. The thick edge goes toward the bike, thin side out. This provides a slight "wedge" to allow the outer cover to star easily , but will tighten the seal as it is pushed on. Half of these that I have removes are on backwards :shock: !

I like to use a thick grease on the bottom 1/2 of the seal, on the inside & outside edge. The thicker & stickier the better. It will fill any minor voids & comes off easily when needed.
 
By holding the seal in your hand, you would have no idea it is thinner on one side. I took it off a couple of days ago so I don't know if it was on the right way or not, but I'm betting it was on wrong!!
Ok now we're really getting somewhere on this job, thanks Skip
 
skipsoldbikes said:
Something else to consider when installing the rubber band seal on the tin primarys, if you measure the cross section of the seal, you will find one edge is slightly thinner than the other. The thick edge goes toward the bike, thin side out. This provides a slight "wedge" to allow the outer cover to star easily , but will tighten the seal as it is pushed on. Half of these that I have removes are on backwards :shock: !

I like to use a thick grease on the bottom 1/2 of the seal, on the inside & outside edge. The thicker & stickier the better. It will fill any minor voids & comes off easily when needed.



I am sure you are 100% right, however I brought a “pattern” chain case rubber on squid bay several weeks ago and when measured with a digital vernier gauge there was no taper on it whatsoever. So it looks like I have wasted my money.
The old saying, “when something look cheap that it looks too good to be true, it usually is.”
 
Perhaps the taper isnt an absolute requirement, but the last 2 I used came from Norvil & I made it a point to measure them, because if the were tapered, I didnt want to put them in backwards. There was a really good magazine article on the correct way to straighten out both componenets of the Norton tin primaty cover & backplate, I will see if I can find it. Of course, the biggest problem was over tightening of the center nut which pulls in the center of the outer cover, & usually needs to be pushed back out to its original position.

Some apply liberal amounts of silicone sealer made for use in an oily enviroment from the local autoparts store (on the bottom 1/2 only!), but I cant imagine what a PIA that would be to remove!!
 
The cases edges have a slight taper to them, so a plain band should still work (?).

If you grease one edge of the pair of cases, and apply vast gobs of silastic/RTV to the other and to the band, you get the best of all worlds.
It will release off the greased edge, and fill all the voids, and seal all the way around.
Finding a still-true set of cases all these decades later is often just wishful thinking, unless owners still have a pristine set...
 
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