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What’s the difference between a road and MTB BB?
My Camino is 68mm I think but how do I know which I need? SRAM GRX says suitable for either but if I go for Uberbike I need to choose between road / MTB.
I’m running 1x SRAM GRX Rival cranks.
Cheers
Rival is SRAM and GRX is Shimano.
Got a link to your bike?
What’s the difference between a road and MTB BB?
Mostly the width.
IANAE but with bottom brackets, you've got the width of the shell, the internal diameter of the bearings/diameter of the cranks and the way that the bearings are fixed into the shell (pressfit/bsa threaded etc).
I believe that mountain bikes tend to have wider bottom bracket shells in order to fit wider tyres.
Isn't it to do with axle length? I.e. MTB axles are slightly longer than road axles?
I assume the OP means Sram GXP BB as well.
I'm running a BB68 BB on mine. Cranks are 24mm spindle MTB, SRAM style (actually Z-Race), and they are 100mm in length. The frame is single chainring only.
On mine, I added a single spacer to the drive side to help alignment, as the crank spindle was about half a centimetre too long for the frame, and the preload cap was binding.
From what I know, BB68 is suitable for road and MTB, the difference being how many spacers (or none) are added on each side. Road I think gets zero spacers added for installs.
Correction: single spacer is on the NDS.
@ads678 yes, I thought that also was because of fitting a drivetrain around wider tyres?
Oops sorry, post nightshift ramblings…
SRAM Rival GXP! (not GRX or DUB)
I think I'll just get another SRAM one, it's lasted long enough and I know it fits.
I was considering going for Hope and seeing what all the fuss is about, but £100 vs £30 and I'll have to buy another tool.
The frame is single chainring only.
No it's not, or at least the latest version isn't. Alpkit even sells 2x full builds, eg:
https://alpkit.com/products/sonder-camino-al-tiagra?variant=39905373159529
Fwiw, the guys at Sonder are super helpful. For a definitive answer I'd drop them a line.
SRAM GXP is same for road or MTB whereas Shimano has different width cups between road and MTB. SO if getting GXP you will be fine.
Im pretty sure if your chainset is GXP you'll need a GXP BB due to the differing axle widths at either end.
Hadn't even noticed that they did a 2x, thanks for the correction.