XT hollowtech BB install question

[homi]

I just installed an XT hollowtech II BB and crank, and it seems to have a fair amount of rotational friction. To the point where the crankarms fall very slowly with gravity. How much friction should there be?

The hollow tube axle looks true and smooth. The friction seems to be in the cups of the BB, which I thought were sealed (?) My entire apparatus is well-lubed.

The BB/crank came off my prior ride and had ~300 miles on it. I don't remember having this much friction with the first install. Any ideas?

[kidwoo]

I wouldn't worry about it unless it's really bad with both cranks on.

BBs need to break in the bearings sometimes.

You can back off the the pressure on the cups a bit but not so much that it enables any play in the BB. If you do this, I'm talking like backing off just few degrees of rotation. Sometimes the cups can cause the bearing to bind a bit.

But normal resistance in a brand new BB isn't unusual.

[mntlion]

spacers set up right?

[homi]

kidwoo - tried your suggestion. not a noticeable difference

mntlion - spaced right. I crushed the plastic tube between the cups the first time by not putting enough spacers in. Replaced the plastic tube and all seems good. It doesn't look like the cups got hurt in this f-up though.

Thanks for the input guys, maybe it will loosen up like you said kidwoo
it's on my first ss, so I guess I'll really get worked

[flowtron]

How do the bearings feel? If they are crunchy/grindy you have a problem...if they are smoove, I think yer ok. I've found that all 2 piece crank/external BB systems spin a little toight compared to conventional bb set ups.

[crashnburn'd]

My entire apparatus is well-lubed....I don't remember having this much friction with the first install.

........

[rideit]

Have your BB cups faced professionally. This is VERY important with outboard bearings.

[homi]

Have your BB cups faced professionally. This is VERY important with outboard bearings.

I've read this before, it makes sense with an ext BB.

........

just trying to keep reader interest. it's a dry topic otherwise

[homerjay]

Did you overtighten the little plastic screw thingy that goes in the nondrive side?

[homi]

Did you overtighten the little plastic screw thingy that goes in the nondrive side?

still sticky even with that thing out
what does it do anyway? seems muy superfluous

[homerjay]

still sticky even with that thing out
what does it do anyway? seems muy superfluous

I think it preloads the bearings much like a star nut does to a headset.