Bicycle Mechanics - 26.0 handlebars in a 25.4 clamp... safe? stupid?

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ElSetho
10-25-06, 11:03 AM
So im continuing my first build... I got my hands on a decent quill, but its clamp size is 25.4. If I was throwing drop bars on this bike, that'd be no prob, but I want to put cowhorns on there, and Im haveing trouble locating those bars with a 25.4 diameter. Is it plausible to stick 26.0mm bars in a 25.4 clamp? Also, maybe someone knows where I can get a hold of some 25.4 cowhorns... maybe...

Anyways, yall have been more than helpfull in this build so far (especially on saving me a load o cash with those ideas for homemade tools). As always, all your help is appreciated guys.. eventually Ill get this thing built...lol.

-Seth


rmfnla
10-25-06, 11:29 AM
Depends on the quill.

I have a cro-mo Ritchey Force (made by Nitto) that I wouldn't hesitate to use for this since steel can handle the deformation that would occur.

I wouldn't be comforable doing it with an Al part.

ElSetho
10-25-06, 11:35 AM
so a steel handebar is alright? cool man, thanks.


TallRider
10-25-06, 11:54 AM
25.4mm bullhorn bars are available, but not as common.
I wouldn't recommend putting a 26.0mm bar in a 25.4mm clamp unless it's a 2-piece separate-faceplate clamp design, which is more forgiving.
Aluminum bars can get crimped doing this, while steel bars may cause the stem clamp to deform. You can get 26.0mm quill stems easily enough on eBay if you know the dimensions that you want.

Philatio
10-25-06, 12:40 PM
so a steel handebar is alright? cool man, thanks.
he was refering to a steel stem, not handlebar.

ElSetho
10-25-06, 01:59 PM
ohhh... alright.

Do any of yall know where to find a 25.4mm bullhorn? I was looking and cant seem to find any. Again guys, thanks.

-Seth

sunofsand
10-25-06, 04:07 PM
Why can't you just sand the bar down a bit?

freeranger
10-25-06, 04:47 PM
Someone correct me if I'm wrong here, but aren't there 25.4mm to an inch? So the 26mm bar is .6mm larger than the 25.4. So, .6mm/25.4mm= .02 inches. 2/100 of an inch does not seem a whole lot to me. Are mfg.tolerances that close?

ElSetho
10-25-06, 05:11 PM
Hey, not sure if anyone cares...

I found a 25.4 bullhorn from Soma Fabrications... took me calling around, but I figured it out. Thanks again for all the help guys.

-Seth

TallRider
10-25-06, 06:32 PM
Someone correct me if I'm wrong here, but aren't there 25.4mm to an inch? So the 26mm bar is .6mm larger than the 25.4. So, .6mm/25.4mm= .02 inches. 2/100 of an inch does not seem a whole lot to me. Are mfg.tolerances that close?
Yes, it's small, but also it does actually matter. A 25.4mm bar won't fit cleanly or snugly in a 26.0mm clamp.


Why can't you just sand the bar down a bit?
You could. But I wouldn't trust a bar to which this had been done, especially if it were a bulged-section bar. A sleeved-construction bar, perhaps. Generally not smart though - these things are built with pretty careful tolerances, and sanding usually doesn't equally remove material all the way around the bar.

To the OP: glad you found a 25.4mm bullhorn bar.

cs1
10-26-06, 02:37 AM
Someone correct me if I'm wrong here, but aren't there 25.4mm to an inch? So the 26mm bar is .6mm larger than the 25.4. So, .6mm/25.4mm= .02 inches. 2/100 of an inch does not seem a whole lot to me. Are mfg.tolerances that close?


Actually, they are. There are so many 26mm quill stems it aint funny. You should be able to score one on ebay or Nashbar in the $20 range. Good luck

Tim

bykerouac
10-26-06, 04:31 AM
Why can't you just sand the bar down a bit?

Please don't do this. Faceplant in the making.

rmfnla
10-26-06, 08:11 PM
Someone correct me if I'm wrong here, but aren't there 25.4mm to an inch? So the 26mm bar is .6mm larger than the 25.4. So, .6mm/25.4mm= .02 inches. 2/100 of an inch does not seem a whole lot to me. Are mfg.tolerances that close?

Yeah, it's not much but aluminum just doesn't respond well to that kind of deformation. Like I said in my first response, if it was a steel stem I wouldn't worry about it.

It is possible to file/sand/machine an aluminum stem to fit this bar, but if the OP was up to that kind of operation he wouldn't have asked the questions he did in the first place.


And, as cs1 said there is no shortage of 26.0 mm stems out there, so why take the chance?