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Discussion Starter · #1 ·
Good Day. Bought a new TCR 2 six months ago. When you remove the chain and grab a pedal and give it a good spin it goes about half a turn and stops.

I thought it just needed to be broken in but 1,200k later it is no better. The local Giant dealer checked it out and said all is fine but it is still tight " causing resistance" This bike is not that much quicker than my Trek Fuel full suspension MTB!!

I am frustrated by the power loss I am getting from this tight BB.

Any ideas guys? Want to get this spinning freely.

Thnxs for any tips from the pro/s
 

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Either the crank was installed too tight against the BB cups and it is binding the bearings, or the bearings are already shot and you will need to replace the cups. If you are experienced & have a torque wrench, you could remove the cranks and spin the cups with the cranks removed. If the BB Cups do not spin or feel gritty/dragging, time for new BB cups. If the cups spin easily with no gritty feel, re-install the cranks and torque to spec. Ride for about 100 miles then check the bolts to make sure they are still tight. The new outboard bearings make working on cranks so much easier.
 

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Third option

capt_phun said:
Either the crank was installed too tight against the BB cups and it is binding the bearings, or the bearings are already shot and you will need to replace the cups.
It could just be that the bearing seals are tight. If when out of the frame, the BB turns smoothly but with friction, then there is nothing wrong with the cups or the installation. A bit of a DIY, but you could pry the seals out and sandpaper the ID of the seals to get a bit more clearance. A bit less dirt & water resistant, but that's a tradeoff you have to accept. Bearing/seal friction losses are tiny in the big picture of all the friction and aero drag while riding a bike.
 

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Discussion Starter · #4 ·
Some good ideas guys. thnxs.

It does spin smooth so believe the bearings and cups are good. I did wonder if the seals might be tight. If it does not work itself loose in the next while I will get into further and get my hands dirty.

wayne
 
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