I’ve found these useful to shim out the front bearings on a pit bike wheel hub to suit the Gemini stub axle.  I’ve used 3 on the inside and 2 on the outside but the hubs do vary so others are different.
Caleb Components, shim washer SW253515

1.6" rims.

Hi, which bearings are you using?
What are you using to mount the rear wheels to the axle?
Thanks in anticipation, Jon.

Stefan, in your reply to BLZeebub, you say you use roller bearings. Do you not use ball bearings?
Most folks I believe use 6003.

1.6" rims.

Hi Stefan
I am feeling a bit stressed out because I think you have answered this before, I am sorry, but now I can't find your answer.

You said you have the 1.6" rims - I think on pit bike wheels, right?

What I want to know is whether the size of rims makes any difference to the size of hubs, and therefore the size of stub axles? Gemini's stub axles are said to have 70mm long shaft, but my hub is more like 90, side to side (from memory). What am I missing?

Sorry to bring up an old thread and to ask about stuff covered previously

Did you include the seals in your measurements? I remove mine and use sealed bearings.

seals were removed, but will check dimensions

I’ve found these useful to shim out the front bearings on a pit bike wheel hub to suit the Gemini stub axle.  I’ve used 3 on the inside and 2 on the outside but the hubs do vary so others are different.
Caleb Components, shim washer SW253515

!! now I understand what the shims are for! doh!

so, did you have the 70mm stub axles?

Hi,
Yes the 70mm stub axles.   I'll have to have have a look at the Bugatti to remember exactly what I put where, but I think you're mostly sorted.

S

Cheers Stefan. Thanks to Jim's hint, the penny finally dropped. I have some 40mm o/d CDS tube and have to fit some stub axles in the ends. Will probably bolt, primarily.