G: Gearbox (Single - Burman) Burman Gearbox Sealing

[Gene Nehring]

Not hard to machine with borazon CBN tip.
Fit in alu on the outside diameter interference fit of 0.02-0.03 then press against axial
So the inner does not spin anymore. 0.05 mm each pass at 100- 200m/min cutting speed.
Not a thing for any lathe...

I worry that 3mm will be way too much to take off the inner race. I wondered wether I might end up braking through the inner race.

 

[Gene Nehring]

That's what Peter did back in the day, he had a batch done. Do I recall we looked at the ones I have which are the correct bearing but no seal??

I think we took a quick look but did not get time to check them. I will make something work. There is a tropical cyclone on its way so I may not be riding in the next few days.

 

[chankly bore]

I think we took a quick look but did not get time to check them. I will make something work. There is a tropical cyclone on its way so I may not be riding in the next few days.

I worry that 3mm will be way too much to take off the inner race. I wondered wether I might end up braking through the inner race.

No, it works fine. I've had many done by a specialist who works for S.K.F. He uses Nachi or Koyo bearings (Japanese) sealed both sides, with C3 clearance. You can leave both seals in, or remove the inner one.

 

[A_HRD]

Just replying to keep Robert W happy ( #26). I must have sold dozens over the years. Never had any negative feedback. They were mostly SKF and a few FAG. I've got 2 left - and 2 gearboxes for a full restoration. But I still have some left for the smaller Matchless/AJS Burman boxes (eg CP box) with a 1-9/32" ID... but I can't find them at the moment - too cold in the garage!
Peter B