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Discussion Starter · #1 · (Edited)
I have a 2005 stumpjumer fsr 120 expert
http://www.specialized.com/bc/SBCBkModel.jsp?arc=2005&spid=21558

I am trying to install some new stylo cranks/bb that I received for Christmas.
http://www.sram.com/_media/techdocs/09%20User%20Manual%20-%20GXP%20Bottom%20Brackets%20and%20Cranksets.pdf

I am having trouble trying to figure out if I need spacers or not for the BB. According to the specialized website and my measuring tape i have a 68mm bb shell. The stylos install instructions say that this means I need a spacer on both the drive and non drive side.

My problem is that when i insert the spacers there seems to be a gap inside the bb shell between the plastic spindle cover (not sure what this is called) attached to the drive side bb cup and the end of the non drive side bb cup.

I am wondering if this is normal or if the spindle cover should be all the way inserted into the non drive side bb cup.
 

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I think that I have this figured out. It looks like I need both spacers and that the gap is normal. The front derailleur is tough to get adjusted but it seems to be working. Thanks to anyone who took the time to look at this thread.
 

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So... the chainline seems to be off with this spacer configuration. The overall width seems correct for the crankset when 2 spacers are installed. I was able to figure this out because if I leave the spacers out the cranks will not tighten up onto the spindle. With the spacers on everything feels solid and tight. However now when I try to tune the front derailleur it wont shift into the largest chainring. The chainrings seem to be too far away from the derailleur for it to be able to push the chain onto the largest ring.

I am thinking that if I move the spacers from the current configuration of 1 on the drive side and 1 on the non-drive side to having both on the non drive side that I should have a better chainline.

I was also thinking that maybe I could remove the spacer from the drive side only but then I would be worried that the cranks would not be tight.

Any suggestions?
 

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The sleeve is connected to one bearing cup when you first insert it into the bb shell. If the sleeve gets knocked off centre during insertion, then it will get pushed further back by the other bearing cup as you screw it in, resulting in the gap that you mentioned.

To verify if the bb plastic tube sleeve actually connects the two bearing cups when used with the two 2.5mm spacer rings, simply assemble the crankset outside of the frame and hold it against the bb shell to check that it fits.

I think you will find that it does fit (ie the plastic tube sleeve connects the two cups with no gaps).

When you install the crankset for real, be sure to use liberal amounts of grease at the surface contact points of the sleeve, the spindle, splines and threads. This creates a grease seal and eases the installation process.

The hollow spindle is tapered (thinner at the non-drive side end) so you have to bolt the crankset until it bottoms out.

As for spacer ring placement: as long as there are enough threads to hold the cups in place, it does matter on which side you put them (eg one on each side, two on the left or two on the right). Use your own judgement to get the correct chainline for your frame.
 
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