25.8mm bars in a 26mm stem?

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25.8mm bars in a 26mm stem?

Postby Jean » Fri May 23, 2008 2:50 pm

Hi,

Just wondering how a 25.8mm set of drop bars (which is a common Italian sizing) goes getting into a 26mm A-head stem?

I gather 25.8mm was established as in-between size in the 'old days' which could be used with either 26mm stems or a smaller '25.?' stem. I suppose that worked fine in the days of quill stems with their wrap around style bar clamp, but does it still work with A-head style stems which have the bolt on face plate?

Cheers
Jean
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by BNA » Fri May 23, 2008 4:02 pm

BNA
 

Postby rustychisel » Fri May 23, 2008 4:02 pm

I would try it, if it clamped I'd ride it. (alloy bars and stem, I'm assuming). Problems happen with 25.8mm bars and 26.4mm stems, which need to be shimmed (usually 1 1/2 rounds of a beer can shim). Manufacturing tolerances can be in the order of 0.2mm easily, as it happens.
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Postby Jean » Fri May 23, 2008 4:26 pm

Alloy stem definitely, alloy bars probably.
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Postby HappyHumber » Fri May 23, 2008 4:43 pm

Cut up a coke can, or similar, and wrap it around the bars at the mount point to give you that extra mm or so's worth of thickness - voila - a simple shim.

I got in just before the Alco-pops TAX and bought a six can pack of Scotch & Dry to get my 25.8 seat post in a 26.0 seat tube. ;)
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Postby Jean » Fri May 23, 2008 4:49 pm

HappyHumber wrote:Cut up a coke can, or similar, and wrap it around the bars at the mount point to give you that extra mm or so's worth of thickness - voila - a simple shim.

I got in just before the Alco-pops TAX and bought a six can pack of Scotch & Dry to get my 25.8 seat post in a 26.0 seat tube. ;)


A shim is always an option, but the purist in me is trying to avoid it. This is not an immediate problem but I'm just thinking through my options for a build I'm planning for later this year or early next.
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Postby LuckyPierre » Fri May 23, 2008 5:26 pm

I think that 25.8mm bars should be OK in a 26mm head stem.
Let me know the easiest way for us to catch up and you can borrow one to see how it goes.
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Postby Jean » Sun May 25, 2008 1:35 pm

Thanks for the offer. The 25.8mm bar in question is presently on my bike so it's not really free for fitting trials at the moment, but when the time comes I may take you up on it.

The build, when it happens, will require a silver polished stem (as opposed to the stock standard of these days - black :roll:) and the only ones I can find are 26.0mm clamp, but lots of the sorts of bars I'd like are 25.8mm. Now if I could just find a good silver alloy bar (outside of Ebay)!

Cheers
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Postby LittleWheelsandBig » Sun May 25, 2008 10:24 pm

25.8 and 26.0 handlebars and stems are functionally interchangeable.
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