Singlespeed & Fixed Gear - bottom bracket width?

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andrew.wetdog
03-01-08, 07:33 PM
I am building up a conversion from an older Gios road frame. I will be getting an IRO wheelset (130 rear) and IRO crankset. What length BB spindle will be correct? My choices are: Italian thread 107, 110, or 113?
Thanks for any input:)
Disclaimer--I have already read from the knowledgeable Sheldon Brown website.

barba
03-01-08, 07:34 PM
That really depends on the crank you want to use.
jdms mvp
03-01-08, 07:36 PM
u can find this out for yourself by measuring as well.

thequickfix
03-02-08, 01:05 AM
IRO cranks are designed for use with a 110mm bottom bracket.
Landgolier
03-02-08, 09:21 AM
110 BB's are just 107's that are 3mm longer on the non drive side. If you install it the regular way, you get the same chainline either way. With Italian, though, you can actually install the BB from either direction and then use spacers to correct the chainline, though there's no such thing as an Italian diameter spacer as best as I can tell so you have to cut a regular spacer so it will expand a little. I've got about 800 miles on a backwards Italian install with no issues so far, my theory is that this is actually better since it can't precess out like Italian BB's normally do, though I guess there's an argument that you want the crank forces on the business side of a cartridge BB. I have an extra 107 Shimano Italian thread BB with low miles on it, PM me if you want it.