outboard bearing cup compatabilty

ClwydPete

Hope this is an easy one for someone out there. Just putting an order together for components to build up a frame this weekend, hence the urgency. I've not fitted outboard bottom bracket bearings before and looking at ribble the shimano sets appear to be specific to each groupset series. I can't believe there would be that much difference across the range of groupsets, anyone know what would go with a sora double..... Alright I'm a cheapskate!

Pete

nicklouse

any shimano HT2 compatible cups.

dont forget to get the BB faced.


see Parktools.

Gussio

I've faced a bottom bracket shell with emery paper wrapped aorund a wooden block. The plastic washers on the HT2 BB give you quite a lot of tolerance.

BigBlackShed

Gussio wrote:

I've faced a bottom bracket shell with emery paper wrapped aorund a wooden block. The plastic washers on the HT2 BB give you quite a lot of tolerance.

Not the same as getting the BB shell faced with a proper facing tool. Do the job once and properly. Never have to do it again. And regardless of what the manufacturer says, they never do it in the factory.

Getting back to the OP. All shimano external BBs are compatible. Just buy the best one you can. Or buy a really bling one, Hope, Race Face or Chris King.

I'm a complete Bike TartTH, so feel free to ignore my upgrade advice.

ClwydPete

Thanks guys, facing the bb sounds like a job for the lbs, 15 quid sounds fair, I'm not confident enough to do the job with sand paper. Thanks for the park tool maintenance site.

Pete

The Rookie

You can't do the job with sandpaper, the point of facing the BB is to make sure it's all 'square' if not the bearings can be tilted slightly relative to the shaft and wear prematurely, how you make sure the BB face is at right angles to the thread within a degree with a block of wood I have no idea, but then I guess neither does Gussio!

Simon

nicklouse

Gussio wrote:

I've faced a bottom bracket shell with emery paper wrapped aorund a wooden block. The plastic washers on the HT2 BB give you quite a lot of tolerance.

that is not facing that is prating about. as you will see below often you have to take metal away before all the paint has gone to get it correct.

No the plastic washers do not take up the variation the cubs still distort.

nicklouse wrote:

Untouched and ready to start.



then chase the threads.



remove the handle to allow the facing tool to be fitted.



Fit the facing cutter.



then face the BB faces.



Not fully done



Done



Other side



remove tool and clean any swarf out.



you are now ready to fit your external BB cups.



Job done.

BOYDIE

Yup get it faced once and you will have a nice square interface,it does increase the dreadful life of external bb's, IMHO I still don't like the external system, yes its stiffer etc, and I can (just) tell the difference when pumping uphill, but for longevity my octalink deore on my commuter is 4 years old and still smooth as silk.

I was getting to the point of OCD every time I could hear so much as a very slight crunch on my GXP/X-type/HT2 BB.I love how the system is easy to maintain, but I was sick of replacing the BB every 6-8 months.


"stepping down of soap box" Sorry.....

BigBlackShed

BOYDIE wrote:

Yup get it faced once and you will have a nice square interface,it does increase the dreadful life of external bb's,

but I was sick of replacing the BB every 6-8 months.

"stepping down of soap box" Sorry.....

I was the same. But I did have a Truvativ Elita crank set. 2 cranksets and 4 bb's in the first year. All on warranty.

Swapped it for a Race Face Cadence crank set and a Hope BB. 2 years on still perfect.