Bicycle Mechanics - 31.7 bar in 31.8 stem?

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JHRacing

07-15-06, 05:53 PM

I have a 31.8 mm FSA (OS 115) stem and was thinking of putting a 31.7 mm Deda bar in it. Since the face plate is totally independant, I find it hard to believe it won't accomodate a tenth of a millimeter difference. Anyone ever tried this?

If it won't work, anyone have a favorite 31.8mm traditional (non-ergo) bar they recommend, especially for use with Ergopower levers?

HillRider

07-15-06, 06:04 PM

Absolutely the same thing. The different numbers are the result of converting the English measurement of 1-1/4" to metric. The equivalent is 31.75 mm so most manufacturers round up to 31.8 mm and Deda rounds down to 31.7 mm. They are identical in diameter.

capwater

07-15-06, 06:05 PM

Should work. Some manufacturers round up (31.8), while some round down (31.7).

JHRacing

07-15-06, 06:14 PM

Thanks much. With all the minute differences in seatpost diams, for instance, I was a little concerned.