Possible to shim a 22.2mm handlebar for a 25.4mm stem clamp?
 

I bought a new handlebar for my recumbent that turns out to have a 22.2mm diameter. Apparently, all of the stems in this size are exclusively for BMX bikes, and none of them are long enough. I'd like to shim the bar to fit in the clamp of the 25.4mm threaded stem I already have, but I'm not sure how feasible this is using something like beer cans or old tubes.

I kind of think it will be ok, since the forces on a handlebar for a recumbent are much lower than those of an upright, but it still is a pretty large difference between the two.

Also, if anyone knew of 100mm+ stems with a 22.2mm clamp diameter, that would work too.

Use flashing.
 

Sure you can shim it.I usually use aluminum flashing-sine I have a roll of it around the house. but beer cans etc should work ok.The cosmetic result might not be as good as a correctly sized bar, but it will be cheaper.The flashing can cut your hand, so be careful fooling with it.You could just wrap the shim material around the bar a couple of times, or you could make several shims and put them one on top of another. Make them slightly less than the diameter of the bar so there will be a small gap.Make sure they are a little wider than the clamp.
Luck,
Charlie

That's going to be a pretty thick shim. The diameter difference is 3.2 mm so the radius difference is 1.6 mm which is 0.063". You will need 1/16" (0.0625") shim stock.

yea I've been thinking about this some more, and I figure as long as I use a one piece shim it ought to be fine. I really don't see several layers of beer can cutting it.

thanks guys