stem for cinelli bars

[danjo]

I have a quick question about stem clamp sizes....

I have Cinelli bars that are 26.4 diameter at the clamp. Is there anything wrong (besides maybe aesthetics) with using a stem with a 4-bolt face plate 26.0 clamp? It seems to fit except there's a larger gap than usual between the plate and the stem.

[cs124]

i'm interested in what some of the more experienced mechanics here have to say but...

...i can't see there being much, if any, problem. as the bar diameter is theoretically* larger than the stem was designed for the face plate won't bottom out so there will be plenty of clamping force. the difference in raduis is quite small so there will be plenty of surface contact to help grip.


* tolerances in the measurement mean that the difference may well be less than 0.4mm anyway.

[Fixed]

bro i do it but that's me
cheers

[11.4]

You're not supposed to do it, and I wouldn't recommend it with a classic pinch stem clamp, but the 26.4 Cinelli bars were quite overbuilt plus they were made from a rather soft alloy that wasn't really prone to stress failures. As a result, you can get away with a lot on those bars that you can't on a new-age bar. You're more likely to be putting some slight extra strain on the clamp of the stem, so don't go to something weird or ultralight -- I've done this with a 26.0 Ritchey WCS stem with no problems but might not do it with a Deda Zero, for example.

If you put a vernier caliper on your clamping area of those bars, you'll probably find that depending on which direction you measure, you'll have a diameter of anywhere from 25.4 to 27 mm. Those bars were anything but round.