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Shimano External BB - road vs. mountain
Last Post 08/29/2014 01:23 PM by Cosmic Kid. 1 Replies.
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08/29/2014 12:47 PM
Been trying to track down a very audible tick on my bike for the last few months. I've tried everything I can think of and the only possibility now is the BB30 adapters epoxied into place. The cups are about 4 years old and spin just fine but figured I'd replace them just to see if the tick is coming from that instead. Went to LBS and they sold me a mountain Shimano BB. It says "mountain" right on it and the instructions even name the cranks it works on. I'm using Ultegra 6800. I measured the cups and the original "road" BB I have is 11mm per side while the "mountain" cups are 10mm. I returned the BB but the employee said they always just use the mountain BB even on all the road bikes that come in. Am I messed up in the head here? Am I wrong? I returned the mountain BB and had to go to another shop to get an actual road BB, in particular a 105 version. Hoping it solves the tick. If not, then the frame is trashed because the adapters can't be removed without completely destroying it.
Cosmic Kid


08/29/2014 01:23 PM
You could put a 1mm spacer between one of the cups and the adapter / frame to make up the difference....but using it straight outta the box will cause play in the crank / bb interface.
Just say "NO!" to WCP!!!!
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