# Giant TCR Composite BB Question



## carlosrj

Alright, I am thoroughly confused with the BB standards and Giant's lack of information (besides Shimano Press Fit) is not really helping.

I have deduced that, given it is Shimano Press Fit, the spindle diameter for the crankset is 24mm. However, I am not sure if:

1) It is a Shimano BB86 or BB92 (and if that actually matters when chosing a new crankset)

2) Can it fit GXP (Is that the same as BB86 but made by SRAM?) or BB386? I heard it was possible if using a new bottom bracket shell.

3) If I wanted to replace the crankset for an FSA Crankset (BB86 or BB90), do I need a new bottom bracket?

Sorry if it is a dumb question, but this BB "standard" is just way too confusing for someone who is new to bike maintenance.

EDIT: If it makes any difference, the frame year is 2013.


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## Marc

In fairness "Shimano Press Fit" is extremely helpful. It tells you the BB is pretty much forever doomed to creak and make noise for the life of the frameset and there's not much of a damned thing you can do about it.

That being said...are you buying a frameset and building it up? Because the Ultegra crank is quite good. And there isn't much of a reason to replace it.


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## carlosrj

Haha, no creaking... yet... (it'll probably start creaking tomorrow now...)

I already own the bike, but this one came with the 105 crankset. In fairness, I am not looking to replace it just for the hell of it (or upgrade it), but I am looking to install a crankbased powermeter (power2max or quarq). 

Power2Max say their cranks are BB86 compatible, but I am not sure if the bike is BB86 or BB92 (or if it matters) and if I need to buy a new BB for the FSA Gossamer crank.

Quarq is a distant second atm due to pricing, but they say theirs are GXP compatible... do those work? Same question for BB applies here as well...


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## Marc

It looks like you need a BB86 crank with a 24mm spindle.

I direct you to this thread with more info: http://forums.roadbikereview.com/gi...-2013-tcr-advanced-sl-317629.html#post4564553


All else fails you can ask FSA to be sure.


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## carlosrj

Thanks for the help Marc. Good idea on reaching out to FSA, I will reach out to them just to make sure.


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## d_tresenriter

Marc said:


> In fairness "Shimano Press Fit" is extremely helpful. It tells you the BB is pretty much forever doomed to creak and make noise for the life of the frameset and there's not much of a damned thing you can do about it.


My 2015 Propel is back in the shop for the second time in 3,000 miles to have work done on the BB. I'll probably have it replaced with a Praxis conversion.


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## SpringSurf

Be careful with the Praxis crank, check spindle diameter whatever you choose. My 2019 TCR came spec'd with Praxis, and the internal derailleur cables rub such that they cut two grooves in the spindle. No one seems to have an answer. Replaced with Ultegra.


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