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Hi, HELLLLLLPPPP!
I'm very confused - I have a Bionx D500, which was originally built into a 29" rim.
I want to fit it to a bike with 26" wheels - so local wheel builder (Big Al at Wheelcraft - so he knows a thing or two) attempted this today. as soon as the spokes are tensioned, it appears to compress the casing and the motor rubs internally - loosening the spokes and this returns to normal.
The UK distributor kindly changed the firmware for me and said they are otherwise the same hub.
So what is different about the factory 26" wheel?
Al says I need to get a super wide rim with big spoke hole stagger to reduce the 'bend on the spokes which contact the casing.
A straight pull wheel can only be built one way, so can't vary the 3-cross.
Anyone got a 26" D series built - and did you have these issues? Any tips?
Thanks
Andy
You could ask Bionx what the recommended/max spoke tension is? (big al builds wheels "tight")
A bit like his coffee
Ha yes,
It doesn't even get to full tension - it becomes a problem when the tension starts to be applied as the spokes straighten.
Getting hold of Bionx is tricky - they have in theory gone bust.
I'm hoping for a response from the UK distributor who had been very helpful previously, but doesn't know about the wheel builds.
Thanks 🙂
Just looked at a picture of a D500 (sorry I was thinking of a flanged Bionx hub and thought you were flexing the shell rather than the case)
I agree with Big Al (as you bring the end of the spoke in towards the hub with a smaller rim you need to move the nipple hole sideways to stop the spoke bending across the motor casing)
29/700 rim
Taking it to the extreme, 20" rim
Yep agreed - but you can buy a Bionx in 26" so I wondered if that rim was set up as you describe.
Big Al knows his stuff - I just wondered if we were missing something Bionx specific.