Removing bushes from sleeve gear and kickstart shaft

BrianK · May 16, 2009

Would greatly appreciate any advice on this topic. I have seen Mick Hemmings' video - he uses a press for the sleeve gear and a tap and vise for the kickstart shaft - and I think he got really lucky on the latter.

I don't have access to a press and am hoping not to have to go to a machine shop.

Oh, and reinstallation tips cheerfully accepted too!

Thanks all - BrianK

Jeandr · May 17, 2009

Unfortunately, I think that is the way to do it properly. I did my gearbox a few weeks ago and a press was necessary to remove some of the old bushes and to put the new ones back in. I even used a lathe to turn the first gear bush to size because after pressing it in, it didn't fit the shaft anymore, I had to take a few thousands off. My friend even has a special fixture to hold the first gear in his lathe to turn that bush so it looks like it is a common thing to do.

Jean

Reggie · May 17, 2009

jeandr wrote;

Unfortunately, I think that is the way to do it properly.

It will be if you have the tools. I have just replaced my kickstart shaft bush, it was a b*****d. I did it by sawing down its length with a jigsaw in two places, and drilling the top hat bit above the saw cuts. It took me about 15 minutes. The hardness of the kickstart shaft means that a saw will barely mark it, but definately the bodgers way to do it.

jeandr wrote;

first gear bush to size because after pressing it in, it didn't fit the shaft anymore

This happened to me with the first gear bush and also on the the kickstart shaft bush. I reamed the first gear bush myself, but with the kickstart shaft being blind, I took it to the machine shop and got charged £18.00 :!: I wondered if it was the poor fitting technique that I had, but if it is common on the first gear bush as jeandr says, maybe not.

Cookie · May 17, 2009

It is common on most bush systems to press them in and ream to fit. They change quite a bit when under tension. You ought to try a truck kingpin sometime.

BrianK · May 17, 2009

Hmmph, nothing from Messrs Hemmings or Eaton re this. In fact, Mick Hemmings says on his video that the bushes should NOT require any reaming (if genuine Norton parts used). Maybe I'll get lucky. Yeah, right....

Cookie · May 17, 2009

Perhaps at one time parts were actually calculated for shrink, I'm still waiting to get a current parts that actually fits.

BrianK · May 17, 2009

Oh, I see trouble a-coming.

How crazy is it to skip sleeve gear bearings in what is otherwise a total gearbox overhaul, every other bearing, bushing, gasket, spring, and seal replaced? I am hoping to get the gearshaft bushes out, god help me, but those sleeve gear ones I don't feel good about removal...

Cookie · May 17, 2009

If they are good and tight they might be better than cheesy new ones. Some folks go though stuff and just replace everything bad or not. In commercial repair we measure and if a part is within tolerance it gets another run. Personally I've seen some real botch jobs from folks installing bushings.

Jeandr · May 17, 2009

Cookie said:
If they are good and tight they might be better than cheesy new ones. Some folks go though stuff and just replace everything bad or not. In commercial repair we measure and if a part is within tolerance it gets another run. Personally I've seen some real botch jobs from folks installing bushings.

I agree, I couldn't have done it without my buddy's expert advice and use of his press and special tool for the lathe. From what he told me and from what I saw in my gearbox, the most worn bush was the first gear bush, the one I had to machine to size.

Jean

Cookie · May 17, 2009

Jean,

If you were doing it again try this, it has worked well for me. Tap a bush with a blunt end tap. Then get a bolt that fits, a nut, and a socket a little larger than the bush. Depending on the socket you might need a washer. Pull it just like you take the pressure off a clutch.
I hate to use the scare y term air wrench here but if you were pulling a bunch of them, say doing several trannies, it can be a time saver.

BrianK · May 18, 2009

Thanks guys. I'll see what I can rig up.

BrianK · May 18, 2009

Are there published specs for things like bush sizes installed, etc? Not sure how I would check to see if they're okay, or instruct a machine shop how much to ream, etc. if not. Tx - B

Cookie · May 18, 2009

I bet if specs exist these one of these guys can tell you.
Frankly one of the hardest things to find these days is a really good machineist. A good one will go by the size of the bushing, material and use. Usually they would mike the shaft and the bushing and tell you if the clearance is excess.

BrianK · May 18, 2009

Thanks Cookie.

Cookie · May 18, 2009

The old gold standard was the machinist did the fitting and the mechanic just checks it before assembly.
Since my guy retired I have only one person I trust. I have a friend way up North who is retired, but will still do stuff for me. Next week I plan to pull the front axle from my Triumph braked Chang and send it up to him for repair. It needs repair from the last machinist I tried to use.
I wish you luck in finding a good guy, look for white hair.

Chris · May 18, 2009

Hi
Just had the same problem with my Quaife.
Ran a lathe tool up the sleeve gear then picked an edge. It was very hard to cut & took a bit of punching to get out.
It seems Quaife use 2 bushes that are scrolled & use a circlip in between them.
Could not wait for Quaife to machine one up so ordered some standard ones from micky Hemmings.
Used the vice to wind them in. Perfect fit & the leak has stopped. (Later Quaife boxes have an oil seal)
all the best Chris

dave M · May 18, 2009

I have never had a problem removing any of the bushes in the gearbox with just a vice and an assortment of sockets and short bits of pipe. I have also found that in the absence of a dedicated reamer the splined part of the shafts with liberal use of WD 40 does a good job of getting the bushes to size.

BrianK · May 18, 2009

Good to hear Dave.

After my experience with swingarm bushes, I'm getting to be an old hand at "reaming" bushes with valve grinding compound.... ;-)

dave M · May 18, 2009

Brian, when you live at least 4,000 miles from the nearest Norton shop, you sometimes need to be a bit of a 'McGiver'. I don't always manage to do things by the book, but so far I always end up with reliable and enjoyable bikes that give hours of pleasure. I wouldn't use grinding paste on the gear bushes though, the chance of some remaining in the pores of the bronze in this relatively high speed application could cause rapid and premature wear. I just clamp the gear shaft in a vice and hold the pinion with it's new bush in a piece of cloth and work it with some lubricant until it becomes nice and smooth. The splines on the shafts are almost exactly like a parallel reamer and it is a hardened steel to bronze interface, so no danger of any damage to the shaft, it just needs a thorough cleaning afterwards to remove any minute bronze particles.

Cookie · May 18, 2009

That does sound like it should work fine Dave. I hate to advise these guys this, but I usually just try to get bushings so that they are free with a light coating of oil. So far no seizures but doing to specs is better.