SRAM DUB - Another thing you didnt ask for to fix that problem you have but didnt know about.

link1896

link1896

Mr Greenfield
SummitFever said:
This is caused by the abomination that is press-fit bottom brackets. If they just would have stuck with good old BSA threaded bottom brackets then you can easily run a 30mm crank spindle with good sealing and large external bearings.
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I concede it's a necessary evil with carbon frames, very hard for a production frame to have a reliable, bonded in, threaded shell. The manufacturers didn't like high failure rates. Efficiency and high reliability drives down costs.

I get why PF exists. The real criminals are the bottom feeders making PF plastic cup, press in bottom brackets with nothing beyond the spindles preload adjuster holding it all together, often with bearings that are a mild interference fit to the spindle. Argh hate hate hate. Looking at you SRAM.

The press fit bottom brackets that thread together, some have huge orings acting as the interface between aluminium bb cups and frame, work well. Sure another two 30 buck tools to make the bastard thread together is a pain. Picking on SRAM, these PF30 ( 46 mm ID,68-72mm wide shell, 30mm spindle) bottom bracket with plastic cups are junk. You can press the cups into the frame with your hands, but need to vary carefully push the second cup/bearings combo onto the spindle once it's already half assembled. Utter crap.

Any frame manufacturer using PF on a metal frame should be thrown off a cliff.
 
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