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Old 09-02-11, 08:24 AM
  #175  
southpawboston
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Originally Posted by robatsu
What is the story on that taillight? It looks interesting.
The housing is a NOS Soubitez Catalux 6 that I scored from an eBay seller in France. I retrofitted it with the internals of a new B&M Seculite plus LED taillight with standlight:





The Seculite is a screaming bright taillight, and the standlight function works very nicely... maintains full brightness for about 4 minutes.


Originally Posted by -holiday76
does anyone have trouble with 175mm cranks hitting pedals on the ground in turns on 650b conversions?
Originally Posted by Sigurdd50
Quoting BikeMan "The bottom bracket will come down a bit with 650B tires, you can expect a lowering of about 8mm-10mm converting from 700x23mm tires to 650x38B tires. So a good 650B conversion candidate will have a bottom bracket height of about 275mm with 23mm 700C tires. More is better, but anything lower than 270 is risky. "
I find this to be pretty accurate. My Shogun dropped 13mm after conversion from 27" to 650B, so that's consistent with Bikeman's estimate of 8-10mm for 700c to 650B conversion. I was patient in waiting for the right frame to come around for converting. The early 80s Shogun touring frame that I ended up with had a very high bottom bracket to begin with, at 182mm. After conversion, it's about 169mm... very safe. Also, if you end up getting more BB drop than is safe, this can be somewhat mitigated by using a narrow crankset and/or narrow pedals. The TA double crankset I chose has a Q factor of only 136mm, so it's very narrow.

For 175mm cranks, I would say you need a BB height of at LEAST 265mm after conversion, or 275mm before.

Last edited by southpawboston; 09-02-11 at 08:28 AM.
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