pfweeks

Which of my two bikes should get the new LX Hollowtech II Crankset I just bought and should I use an XTR Rear derailler on my commuter?

Here's the dilemma:

1. I bought a bunch of stuff to convert my Commuter ('94 LX 7 speed cassette) to XT level 8 speed.

2. I also bought a brand "new" bike, a pristine 2001 GF Hoo Koo E Koo Disc
which will be my new trail bike. This bike is practically bike shop new and has never seen a mile of off-road riding. This is going to be my new off-road rig.

Included in the stuff I bought for my commuter is an FC-M542 Hollowtech Crankset and bottom bracket. Now I'm wondering if it might not be a better choice to take the practically new Bontrager Sport off the GF to use on the commuter and beef up the off-road bike with the new Hollowtech II crankset?

I also bought a used XTR RD-M950 for the commuter to replace the '94 LX rear that has served me so well(the '94 LX has aluminum Carmichael pullies). I've heard/read that the '94 7 speed LX also works for 8 speed. Would leaving the '94 LX on the commuter with the new 8 speed cassette be more prudent than sending an(albeit used) XTR out in the rain?

Oh one more, please. I've read that "facing" your bottom bracket shell is important with these new external bearing cranksets. Is that something I really have to go to a bike shop for or can I just sand the paint off the edge of the bottom bracket shell with a block of wood and some sand paper?

Thanks in advance for your help in bringing my bike knowledge into the 21st century.

bikeman715

you need to g to to your LBS to have your bb refacing . is there a problem with the bb set going in ? if not i wouldn't worry about it. by any mean don't do what you suggent .

pfweeks

Thought I'd bump this post of mine from several years ago to update my experience with external bearing bottom brackets on frames that pre-date external bearings:

1. My 2001 Gary Fisher Hoo Koo E Koo Disc - Took it to one of the best bike shops in the Boston Area (Belmont Wheelworks) as a stripped frame and they wouldn't take my money to face my bottom bracket. They claimed it was faced at the factory and I could just install the Hollowtech crank. I took the frame home, layed it on a linoleum floor and used a single-edged razor blade to take the paint off the face of the bottom bracket and then installed the crank. Three years later, no problems whatsoever.

2. Bought a 2001 Custom Titanium Spectrum frame and paint-matched Reynolds Ouzo Pro fork about 2.5 years ago. Bought an Ultegra SL crankset and Chris King bottom bracket and headset. Didn't even bother checking with the LBS this time as I know Merlin meticulously faces Tom Kellog's frames after welding them. Layed the frame on the kitchen floor once again and used the single-edged razor blade to take the maroon Imron paint off the BB faces. 2.5 years later, no problems whatsoever.

YMMV

JiveTurkey

Folks sometimes forget that the need to ensure the BB shell faces are square to each other didn't come about with external BBs. It was there for old cup-and-cone BBs, too. Facing is needed to keep the two bearing cups parallel to and in line with each other. The only BBs where this wasn't an issue are the cartridge BBs where the two cups are fixed to each other.

That said, the BB shell faces may pretty much be square out of the factory, but it's still a good idea to get it checked. The mechanic doesn't have to remove any material if they're already even and squared.

If you're pretty sure it's good to go, you can also install the external cups and slide the spindle through and see how easily it slides in. If it catches on the far bearing then things aren't right.

pfweeks

I agree on all of JiveTurkey's points above. The reason I thought my Gary Fisher needed to be faced was because 2001 was smack dab in the middle of the cartridge bottom bracket era and I figured if they were ever going to stop paying attention to facing, that would be about when they would slip in that aspect of quality control.