Singlespeed & Fixed Gear - replacing cup & bearing BB w/ a cartridge BB
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Can you advise me on the correct bottom bracket size I need? I've replaced the original cup & bearing BB with a cartridge BB. I purchased a Tange BB 107 and it's too short on the right by 3mm. It's perfect on the left side. I need to push the right side out by 3mm so that the crank doesnt hit the frame. I'm using an old 80s Sugino double-ring crank 144 BCD. This is for a fixie conversion.
Do cartridge BBs come with varying legnths for the right spindle arm? Should I put a few 1mm BB spacers on the right side?
I'm hoping that I wont have to resort to going back to the oldschool cup & bearing BB.
Here's a picture of what's going on.
12-09-07, 10:07 AM
How is the chainline right now? Is it perfect but with clearance issues?
12-09-07, 10:33 AM
107 + 2*3=113mm
12-09-07, 11:15 AM
^your math is impeccable and the solution is correct. just get a 113 bb. (extra 3 mm on both sides)
chainline is perfect. i guess i'll need to push the crank out 1-2mm to distance the spider from the stays without affecting the chainline too much.
12-09-07, 02:14 PM
I'm just gonna throw it out there that you might have a case of mismatched tapers (JIS crank on an ISO BB) there... not the end of the world, but you might be better off matching tapers. This will move your chain out approx. 4.5 mm according to sheldon.
I had a mismatch problem and it looked identical to that setup.
Edit: Tange is JIS from the looks of it so wtf do i know. Still might be something to look into though.
To gain a little clearance while running the ring on the outside, you can file down those little horizontal tabs that the top arrow is pointing at in your pic there. I did this on my 600 cranks and it worked fine.
thanks for your input everyone. this forum is quite helpful.
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