Metal Flakes in the gearbox oil?

The Hemmings DVD is available to order from the Norton Owners Club in the UK. I can lend you my copy if you want, I'm in Vancouver.

Alternatively, this YouTube channel as pretty good rebuild detail for the mk3 but this is nearly identical to mk2 save for the gear selector cross shaft:
(Owner forgot to put this up as shareable on other sites, so just use the Watch on YouTube link to see it)


I am planning to help a local owner in a week or so do a partial gb rebuild, as the kicker is not engaging at all. He is in North Van, perhaps if you are able to come out you can join us...

I had a quick look at the Youtube video, (I'll watch it all later) they are doing the work with the gearbox out; is the MH video with the gearbox in the bike or out?

I'll open the outer and see what I've got, then take the inner off. I hope its something obvious that I can deal with. Depending on issue, I may take you up on your in person visit, thanks.
 
I have never opened up a Norton gearbox and found the teeth on ALL the gears pristine.
And every time I change gearbox oil, if I look hard I can see fine bronze particles in the oil.
There is always a judgement call in terms of how many and the size of the particles, when the oil was last changed, has any symptoms changed (noise, shifting), etc.
In this case a teardown seems like a good idea.
 
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Thank you L.A.B.
Out.
Here it's in.

Shifting was the only change I noticed before seeing metal flakes in the oil
I have never opened up a Norton gearbox and found the teeth on ALL the gears pristine.
And every time I change gearbox oil, if I look hard I can see fine bronze particles in the oil.
There is always a judgement call in terms of how many and the size of the particles, when the oil was last changed, has any symptoms changed (noise, shifting), etc.
In this case a teardown seems like a good idea.
 
I have never opened up a Norton gearbox and found the teeth on ALL the gears pristine.
And every time I change gearbox oil, if I look hard I can see fine bronze particles in the oil.C
There is always a judgement call in terms of how many and the size of the particles, when the oil was last changed, has any symptoms changed (noise, shifting), etc.
In this case a teardown seems like a good idea.
The Bronze bushes in the 4th sleeve gear (press fit) takes a lot of wear, and the First gear layshaft which has a bronze bush press fit see a lot of wear. At least when I open up the gearbox, that is where I look. I use the MkIII sleeve bushes as they are longer and don't tend to move around. More friction surface area. Or use the shorter bronze bushes and an old bush in the middle between the new ones. I place the sintered bronze bushes in oil the night before installing them into the gear. Then I assemble the gearbox.
Cheers,
Tom
 
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You really do need to eyeball all of the above and I'd also throw in checking of (IIRC) 2nd gear set and case cracking (between two roller types, close to the engine sprocket). LOL, I had the case, useless bearing and that gear pair all horrible.

Regards
Sean
 
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