I've just bought a used 2010 Giant TCR Advanced SL 0 Rabobank frameset to build up as a project bike. I'm planning to use 2012 SRAM Red for the drivetrain, and fortunately the frame came with a GXP BB already installed. The frame is BB86, and I can't tell if the bearings I have are steel or ceramic. The bearings bodies are blue plastic, behind the red seals. Google Images shows that there are blue and yellow ones out there, but I can't find any conclusive authority on the matter. Anyone able to shed some light on the issue?

Does it matter? if they run smooth is the issue is it not?

To be fair you have more worrying things to consider with a GXP

Quick fix (and cheap) let me know if you want details

Not a performance issue in the slightest, but like everyone I like to know what my machine's built of. No idea what you're talking about with quick fixes.

Fair enough I see why you would want to know

I was referring to the non drive side bearing issue that you will have with a Sram GXP bearing set.

The Crank spindle bearing seat does not match accurately enough with the inner of the bearing, meaning that the bearing and spindle "rest" on each others edge rather than where they should, leading to premature bearing failure. If you want it to fit precisely I'll post how, or you can replace the bearings with more GXP ones later on

Cula, this is very interesting. Please tell us more.

If you could go through the trouble of explaining the problem in detail and then describe how you would fix it, this board would be most appreciative.

Thanks.

Spacepolice, I think you have the standard bearings.

FWIW I have had no issues and the press fit GXP bearing for BB86, (only 3000 km so maybe problem may yet arise). They are also super smooth with not too much bearing drag.

_________________

Sweet, sounds like I should take your advice Cula, but not until AFTER I've ignored your advice, trashed my standard steel BB bearings, and thus given myself an excuse to pimp my bike with ceramics Seriously though, haven't heard of this issue with GXP before, would be interested to know your fix, as I'm still waiting for a new wave washer to arrive before I can install my new crankset.

Ok, as you (and others) may or may not know the GXP BB from SRAM is designed to trap the non drive side bearing inbetween the thicker bit of the spindle and the non drive crank arm, this then will stop any side to side movement of the crank and spindle whilst eliminating any risk of of both the internal races from both sides of the BB being pulled together like in some other systems, anyhow in doing so this then created the need for the non drive side bearing seat to be smaller in diameter than the main spindle (to create the Stop or Shoulder as it were for the non drive bearing to butt up against)

Problem with this is that now the spindle is ground to a slip fit for 22mm (21.95) and the supplied bearing is an imperial 7/8ths (22.2)
The bearing with the correct dims are very hard to find, if at all they exist. SRAM say just tighten it up so it connects with the shoulder and it won't move if its got the correct torque value. This imo is a $hit answer and is unacceptable as the precisely ground bearing seat is then unused and all of the force on that side of the crank/bike is resting on less than .5mm radius. They done it properly on the drive side as the bearing (24mm) and spindle difference is 0.05 a nice slip fit (to be fair it SHOULD be a slight interference fit but hey ho)

The next time you have a GXP crank out, pop the non drive bearing onto the spindle and see what I mean about it not fiting right

For your info, I popped into a leading online bike store and spoke to one of their Mechanics (Sorry not going to post who) about this and compared what they had in stock (ALL with the same problems with dimentions standard and Ceramic) and his reply for my solution was "Well if you want a precise fit, you could do it that way"

Funny enough, yes I DO want it to fit precisly. SO these are your options imo

Buy this http://www.chainreactioncycles.com/Mode ... elID=26899" onclick="window.open(this.href);return false;"
You would need to get the correct bearing though to fit, I think a standard hope BB is the right one as this just converts it into a GXP.
Found this thread that might be usefull viewtopic.php?f=3&t=95629" onclick="window.open(this.href);return false;"
I don't know how good the fit is though on any of this (Could be just as bad!?)

Or buy the Truvativ upgrade bearing kit, fitting instructions so you can see the insert collers http://www.enduroforkseals.com/sitebuil ... _rwc_f.pdf" onclick="window.open(this.href);return false;"
Likwise I have not tryed this so do not know what the overall fit is like

Or what I did was buy a 25x37x7 bearing this then fits into the BB and at work turned up a collar to fit exactly


If want to get someone to make it up for them on a cnc I have a dxf to eliminate most of the cost


Hope you get it sorted or don't experience problems