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Hi Chaps,
Is anyone running a Hope BB with a GXP crank using the hope GXP convertor kit?
I'm finding it hard to figure out what spacer config should be run on a standard 73mm BB shell.
SRAM GXP cranks run no spacers on a 73mm shell.
Hope BBs all state to use 1 X 2.5mm spacer.
Some forum posts also say the same thing, and others say to use the SRAM way...
What actually works?!
Cheers chaps!
Ricks
Go with the Hope instructions, it's their BB the SRAM one is probably a different shell width
GXP crank axles float in the driveside bearing, and usually have probably 6ish mm of clearance between the cup and crank inner face (before you make your next post asking if there should be a gap 🙂 ), so the spacer is fairly academic, fit it and the axle is supported a smidge further out, leave it out and the cups thread in further.As long as you have the gap there, doubt you'll notice any difference, but i'd probably fit it.
So, does the converter shift the chainline?
i tried and tried and tried with my XX1 crank and a Hope BB...
with the 2.5mm spacer installed the cranks wouldn't spin, with nothing in the BB would work it's way loose... i bought some spacers that were 2mm (stiff on spinning), 1.5 (bb worked loose)... i was fed up of using SRAM BBs that last about 4 rides & in the end i gave up and bought a Hope crank and BB when a 20% off ebay malarkey came up...
the 2.5mm spacer is for shimano cranks.... you're not installing a shimano crank.... you're installing a GXP one, and that doesn't have spacers...
people will tell you it will work... i could not make it
Well I had my old x9's and GX11sp fitted with the Hope BB and 1 spacer, I swapped it to the other side to adjust the chain line, worked perfectly.
It sounds like the tolerance in the BB shell can either mean the conversion will work fine, or not.
I wonder why the BB would work loose with no spacers in though.. too much load on the drive side bearing?
I've run GXP cranks in Hope BBs just fine for years, threaded and press fit both. Got an XX1 set in a PF92 BB right now that's been happily spinning away for three years. As mentioned the DS side floats free, it's a really simple system. Read the instructions. Get the bb chased and faced properly if its threaded. If the cranks won't spin there are too many spacers in there. Consult your lbs if you can't figure it out.
I found a comment from Ben (from Bird) on another thread, which suggests that the adaptors move the chainline in by around 1mm. Probably not enough to notice for most folk, but maybe an issue (on the biggest sprocket) if you are running a chain device.