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View Full Version : bottom bracket bearings gone??

vqdriver
10-05-2014, 04:46 PM
i've got a 10sp ultra torque crankset that's seen a couple thousand miles. it runs smooth except when i'm in a big gear and strongarming the pedals. then i can feel a sort of rough grinding. on the stand i can replicate by shifting up and pushing hard on the pedals by hand and it feels like the bearings going in and out of detents. at least that's what it feels like. once momentum takes over and i can no longer apply enough pressure to the pedals, that roughness goes away.

i suspect the bb bearings are shot. sound about right?
how come i don't feel this with no/light pressure on the chain?
dave thompson
10-05-2014, 05:01 PM
I supplied NFS lube to my wife's twp friends that did the TransAmerica cross-country ride. New cassettes and new chains were installed before their tour and NFS was the lube I used when setting up their bikes. I also sent them out with a bottle of NFS for use along the way. Over 3,000 miles each and no chain issues whatsoever. They used a little more than half the 2oz bottle along the way. NFS isn't cheap but it is a great value per mile/dollar. It's a staple in my garage.
dave thompson
10-05-2014, 05:02 PM
sorry, wrong forum
shovelhd
10-05-2014, 05:19 PM
The only way to know for sure is to pull the crank and check the bearings unloaded.
FlashUNC
10-05-2014, 05:23 PM
The only way to know for sure is to pull the crank and check the bearings unloaded.

Yup. Time to pull the crank. Only way to be sure.
oldpotatoe
10-05-2014, 05:48 PM
i've got a 10sp ultra torque crankset that's seen a couple thousand miles. it runs smooth except when i'm in a big gear and strongarming the pedals. then i can feel a sort of rough grinding. on the stand i can replicate by shifting up and pushing hard on the pedals by hand and it feels like the bearings going in and out of detents. at least that's what it feels like. once momentum takes over and i can no longer apply enough pressure to the pedals, that roughness goes away.

i suspect the bb bearings are shot. sound about right?
how come i don't feel this with no/light pressure on the chain?

Take crack off and spin bearings with your fingers, that'll tell ya.