Originally Posted by
mijome07
I have a stock Truvativ Touro 50/36 compact crankset with a 68x108mm BB and a 45.5mm chainline (?). Pretty much an outdated square tapered crankset. And a 12-26T 9-speed cassette in back. I'm leaning towards a 34T x 11-32T setup.
The BB needs to be replaced and my options seem limited. I found a Shimano UN54 BB in 2 potential sizes. Reviews seem pretty good and they are cheap.
I'm trying to get the straightest chainline for this setup. Should I get a 68x107mm and run the chainring on the outside (I'm adding 2 bashguards) or get the 68x113mm and run the chainring on the inside?
Is there something I'm missing? This is all new to me. I'll appreciate your comments and/or expertise.
You been drinking too much of the Outboard Bearing, Latest-is-the-greatest Kool-Aide I see
No, square tapers are not out of date, nor inferior. There's many BB's to choose from, and Shimano is far from you only choice, I wouldn't buy the UN-54 because of the plastic cup. Shimano has basically cheaped out on the tapered BB business, and want you to get their latest stuff, which is no better than the previous.
Here is just one place that has some tapered BB's :
http://www.biketoolsetc.com/index.cg.../Taper-Spindle
The Tange LN39 and 59 are very good. The RPM ones are also good. I wouldn't bother with the YST brand. Sunrace, I don't know.
What is the frames spacing, 130 or 135mm?
The singlespeed forum may be able to help you better with chainline setup.
