layshaft bearing-bushing up-grade

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I bought a "strengthened Gearbox" (case) from Mick and when I asked about the Layshaft bearing he told me that the roller was a bad idea and he sold me the ball bearing.

Vince
 
Regardless of what bearing you use, checking the end play on the shaft is a good idea. Some people treat the shimming like it is a colonoscopy but it isn't a big deal. And yes, heat the case with a heat gun and do it in the bike if you want. The main bearing on the other hand is a regular bitch to pull off without taking the gearbox out of the bike!
 
Got the inner cover off o.k. The top dowel pin had a bit of rust around it and was stopping the cover from sliding off. Blast from the map gun cured that. All the gears etc came out. Now I am having a problem getting my layshaft out. I have tried the old hair dryer - no luck. Hit it with the map gas - no luck. I was a bit wary with the map gas as I don't want to over heat the area and damage the main shaft seal. Or am i just being a Nancy? Any suggestions?
 
Mark, there's a recall on map gas cylinders, some have caused explosions. Wouldn't want to damage the Norton. Sorry for side tracking the post. Graeme
 
You tried a hair drier? Not hot enough. Get a HEAT gun. Move it around in there for about 5 minutes. Give a sharp pull on the layshaft. It will eventually release
Doug
 
Mark F said:
Now I am having a problem getting my layshaft out. I have tried the old hair dryer - no luck. Hit it with the map gas - no luck. I was a bit wary with the map gas as I don't want to over heat the area and damage the main shaft seal. Or am i just being a Nancy?

You are certainly not using enough heat.
 
Might as well just buy a new seal and get it over with. Hot enough to sizzle spit is about the right temp.
 
It's kind of hard to get the heat into the right spot but the map torch gets in pretty close. Is it a bit too severe for this? You don't think it will damage the mainshaft seal? Maybe I was being too much of a woose and just need to go a bit longer. I will get a heat gun if it is any better.
Recall on Map gas cylinders? Mine is one of the old slim ones. Almost empty now.
LAB the bearing number you quoted is the same as the old dodgy one except for the TB on the end of it.
 
rvich said:
Might as well just buy a new seal and get it over with. Hot enough to sizzle spit is about the right temp.
It's starting to look that way. The primary is still only half assembled so not too much of a big deal to rip the inner case off again and slip in a new seal. I suppose after all that heat in the area it would be advisable. :(
I seem to take one step forward and two or three back at the moment. No wonder it's still not finished!
 
rvich said:
Might as well just buy a new seal and get it over with.

When I did the job, I had already removed the primary cases so I could play the torch flame directly onto the outside of the gearbox casing in the area surrounding the bearing and if I remember correctly, it didn't take very long before the bearing came out with the layshaft.
 
Mark F said:
LAB the bearing number you quoted is the same as the old dodgy one except for the TB on the end of it.

Yes, the "T" is the important bit (but it's also a better quality bearing). The TB bearing has a flexible phenolic cage (T = Textile laminated cage) which doesn't break up like the standard bearing cage because it's the cage breaking up that causes the bearing to fail.
 
O.K thanks LAB. If the seal is going to be toast anyway(no pun intended :lol: )I might as well pull the inner primary off now and heat it from behind.
Don't suppose you know if the bearing is a Mick Hemming's special or just a standard bearing that will be available at any bearing suppliers?
 
Mark F said:
Don't suppose you know if the bearing is a Mick Hemming's special or just a standard bearing that will be available at any bearing suppliers?

I know from past discussions that some of our members have been able to order it from a bearing supplier, but make sure you know how much they intend to charge you, as the price of that bearing seems to vary considerably.
 
Thanks for your help LAB. Much appreciated. I will try and get one locally(if they are open at the moment) otherwise I will go through Mick. Which I don't mind. It's just the delay. Another week or two.
 
With a heat gun you'll need alot of heat.Best to do when ambient temperature is favorable.If you dont have a slide hammer try some threaded rod with your largest socket and improvise something.
 
pvisseriii said:
I went with a roller bearing upgrade and went through the shimming crap. Things just were not right with the kickshaft and what not. I pull it out and went with a good quality ball bearing and sleep better with it.

The roller just isn't necessary and is not worth the shimming mess. Although the Portuguese bearings should be removed, a two piece roller replacement is just someone idea of expanding the superblend.

Again, a good ball unit will be better IMHO and stay away from that shim sh-t.

Honestly I don't know who introduced that exaggerated shimming of the layshaft when using a roller bearing. Apart from a nice tight kickstart shaft it serves nothing.
Actually your gear cluster is better off with some layshaft side float for smooth engagement. Don't fool yourselfs a roller bearing with E specs can take far more load then any other ball bearing and provides easy removal of the layshaft/gears. A good quality ball bearing might be sufficient for road use but never ever again I will race a Norton without that roller bearing!
 
Ambient temp here today was 39.9 C! Same tomorrow. Is that hot enough :lol:
I've got plenty of large sockets but don't know how I would attach any to the layshaft. Don't worry I had thought about it.
 
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