Saturday, May 5, 2012

1995 Yeti ARC build continues

This bike is a prime example of the idea that slow progress is still good progress! It seem that no matter the build and how good your parts are, there will always be surprises and delays. The struggle today was with the cranks / bottom bracket, fortunately it all worked out.

As any build goes there are iterations. Originally we chose a parts package predominantly comprised of Shimano's M900 XTR gruppo, but along they way the cranks changed over to Toplines, brakes to Critical Racing and wheels to Ringle. Most of those changes are pretty benign and don't involve any other components, but in this case the cranks proved to be a problem.

For starters I assumed that the 175mm long pair of Toplines were compact drive (they did use smaller BCD rings) and therefore I could use a 108mm UN91 bottom bracket (one of my favorites for its reliability and overall performance.)  I started to instal the BB into a freshly reamed BB shell with seemingly clean threads. Drive side went in smoothly but the non-drive side cup was binding. Fearing a slip of the wrench and paint damage I took it slow and quickly realized something was wrong. Backed out the cup, cleaned, re-greased and tried again, no luck - the tool was slipping and stripping the cup. Ok, now what?? No metal filings anywhere, so I didn't cross thread. I didn't recall any problems with BB extraction during frame disassembly so what's the problem. Driving in an flimsy Aluminum cup seemed like a losing proposition, but fortunately I keep a steel cup around for just such an occasion. After a few attempts of slowly making progress, cleaning, greasing and going back in I was able to chase the threads and drive the steel cup all the way in. Next come the cranks, only to realize that the BB spindle was too short, they are not compact drive... d'oh! Fortunately I had a very nice White Industries Ti bottom bracket I was saving for another ARC. The bearings were past their prime but with the aid of my new arbor press new ones went in and the BB went on the bike without any problems.

With the chain-line set next the cranks. I decided to go with M900 chainrings with Ti bolts and fresh spacers. Of the three to four pairs of Topline cranks that I have these are the only ones with the milled out spider, a very nice touch. The cranks were topped off with Titanium extractor bolt, very similar to a Syncros Crank-o-Matic.

The Critical Racing brakes went on without much fanfare. All were cleaned and lubed with liberal amount of anti-seize to ensure long lasting performance. I love the way these brakes look and they seem much easier to adjust than those pesky Graftons. Ritchey pads complete the braking setup.

Next I swapped in a much better condition Ringle Moby post, perhaps a bit too blue... I had to get three separate posts to find one suitable for this built. This one came with a broken head, but fortunately I had a spare turquoise head from a broken post, so that worked out nicely. I'll wait for the third one to show up before making a final decision.

Decided to try a couple different bar options, still waiting for a turquoise Ringle stem before settling on the best choice.

Personally I think a turquoise stem is a must, and either the silver or turquoise bars will work fine at that point.

So, that's the progress for now. The cable stops are pretty faded and need to be reanodized before going on, so it may take a week or two to get the bike properly strung up.

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