I have a Cannondale CAAD12 with a BB30A. The "A", as you probably know, means that the BB is not symmetrical and sticks out and extra 5mm on the non-drive side....for some reason. I it is still just 73mm wide however.
I also have a Quarq Elsa R powermeter that I just took off an older PF30 BB frame which is also a 73mm wide BB. It gave me years of service on that bike with no problems.
However, for some reason, as I install this thing, I get nowhere near the 48-54Nm of torque specified before I start to get a lot of bearing drag. A LOT. Like I'm worried that I'm going to shear off the snap-rings inside the BB and press the bearings all the way to the middle. I started tightening it yesterday but something seemed odd so I stopped. Then I tried to spin the cranks and they almost wouldn't spin!
Quite literally, finger tight is enough to remove all play.
There is a 10mm spacer that goes on the drive side and then there is that split washer that takes up the play after you tighten everything down. They're both in there where they're supposed to be. Those are the only spacers, and the split washer (with the allen bolt) is backed all the off. Still, I can get absolutely NO PLAY at a ridiculously low torque.
When I look at it, tightened down to a point where there is no play, the chain line looks like it will be ok. The distance between the small chain-ring and the chainstay looks similar to what I have on my other bike. The whole thing just seems weird though.
Did my mechanic not seat the BB30 bearings all the way against the snap-rings when he installed them? I can't think of another reason why it wouldn't fit correctly.
Anyway, any advice you can give would be much appreciated.
I also have a Quarq Elsa R powermeter that I just took off an older PF30 BB frame which is also a 73mm wide BB. It gave me years of service on that bike with no problems.
However, for some reason, as I install this thing, I get nowhere near the 48-54Nm of torque specified before I start to get a lot of bearing drag. A LOT. Like I'm worried that I'm going to shear off the snap-rings inside the BB and press the bearings all the way to the middle. I started tightening it yesterday but something seemed odd so I stopped. Then I tried to spin the cranks and they almost wouldn't spin!
Quite literally, finger tight is enough to remove all play.
There is a 10mm spacer that goes on the drive side and then there is that split washer that takes up the play after you tighten everything down. They're both in there where they're supposed to be. Those are the only spacers, and the split washer (with the allen bolt) is backed all the off. Still, I can get absolutely NO PLAY at a ridiculously low torque.
When I look at it, tightened down to a point where there is no play, the chain line looks like it will be ok. The distance between the small chain-ring and the chainstay looks similar to what I have on my other bike. The whole thing just seems weird though.
Did my mechanic not seat the BB30 bearings all the way against the snap-rings when he installed them? I can't think of another reason why it wouldn't fit correctly.
Anyway, any advice you can give would be much appreciated.