tranny binding

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I have put norton trannys together before, but this time when I torque my inner cover down it binds up. I have through trial and error pinned it down to the layshaft.Im pretty sure the new bearing I put in seated all the way because of the sound it made when I tapped it in. And by looking at the gear that goes up against it looks very close to the wall of the tranny case.I was wondering if anybody has a measurement of how far that gear or how close that gear should be.
 
If you had to tap the bearing in then there is a good chance that there is a burr behind it. The bearing should be dropped into a hot case and seat with a definite 'clunk' - if not , heat the case, shock the bearing out and try again.

Have you got the gear referred to as layshaft 4th round the right way ?

Have you had the kickstart inner bush out ?
 
79x100 said:
Have you got the gear referred to as layshaft 4th round the right way ?

Which is with the raised shoulder against the bearing, if you're not sure which way is correct?
 
Earlier this week I assembled my gearbox with new bearings for the main- and layshaft. When properly seated I believe the outer races on both bearings should be at the same "depth" level.

Regards, Per
 
Yes the 4th gear layshaft is in the right way.However now im having trouble getting the layshaft out because I had to heat up the bearing yo put the layshaft in.I am going check(when I finally figure out how to get that shaft out) to see if they are sticking out the same amounts. thanks.
 
The layshaft is supposed to slide in easy in the layshaft bearing, no tight fit. When you get the layshaft out you need to "polish" the shaft end area that fits in the bearing.

/Per
 
Use a roller type ,the inner race will be pressed on the shaft and the outer race and rollers will be fit into the case. So you only have to install the shaft with inner race into the bearing when assembling the trany.
 
On the roller bearing I installed the inner race had a flange that was supposed to be on the inside of the bearing so it had to be installed together with the rollers and outer case.
I don't think the inner race should be a tight fit on the layshaft because rollers won't take axial load.

Regards,
Per
 
Don't polish the layshaft yet, sounds like the bearing has gone in at an angle and has extra hoop stress making the inner ring smaller and giving an interference fit to the shaft.
 
Per G said:
On the roller bearing I installed the inner race had a flange that was supposed to be on the inside of the bearing so it had to be installed together with the rollers and outer case.

Per,

As I have always understood it, the flange on the inner race faces 4th gear?
From what you have described, you have fitted the bearing around the other way, with the flange towards the case?

As it would be normal practice to be able to remove the layshaft and inner race from the roller bearing without disturbing the outer race.
 
LAB, after another look at the Mick Hemmings video I believe you are absolutely right, the flange is supposed to be pointing outwards opposite to how I installed it.
I'm still confused, it makes no sense to me having the flange on the outside when the bearing takes no axial load? And why is Mick pointing out the importance of not installing the layshaft in the inner race with a tight fit? I thought that was so you could remove the layshaft without disturbing the bearing. I checked the layshaft and inner bearing race for a nice fit before thee were installed.

Not sure if I need to tear it down and turn it around, if you can run it with a roller with no flange at all as shown in Mick's video maybe it's ok to run this season as it is and fix next winter?

I did use one shim on the layshaft and compared to the Old Britts procedure and recommandation I ended up with a slightly larger end float.

The gearbox is back in the bike and I'm almost ready to go :cry:

Regards,
Per
 
Is it not possible, with the flange on the outside that it could move further out than the bearing outer and run against the case housing ?

I think that I would turn it round.
 
79x100, Good point, not too much fun if that happens.

It s-cks, but I need to get the inner race turned around, will be "interesting" to do it with the gearbox in the bike. Luckily, the layshaft bearing was not that tight in the case and with a little heat on the case it should be possible to get it out without damaging the bearing.

Travelling the rest of this week but now I know what I'm gonna do next weekend. Let's hope it's raining this weekend!

Regards,
Per
 
Last night I disassembled the gearbox, fixed the layshaft bearing inner race (and yes I was wrong, it makes sence with the flange outwards) and assembled the bike again.

This morning I took a first short test ride without helmet (to be able to listen to any noise) and all gears works very nice :D a little noise from the primary chain. Back in the garage, adjusted the primary chain.
Took a 10 miles test ride, working up-down thru the gears, all works perfectly fine :D :D

Cheers, Per
 
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