Handlebar shim DIY
 

I'm not sure if everyone goes about it the same way, but I thought I'd document the handlebar shim I made yesterday. After not finding the right one for sale at any of the bike shops nearby, and not wanting to wait for something to ship, I fabricated my own. In this case, needed a .4mm shim to mate my 26.0mm Modolo bars with a 26.4mm Cinelli stem. I had some .5mm aluminum sheet stock on hand already. First I measured the stem at its widest point. I then cut a strip of aluminum sheet stock that width but slightly longer than the circumference of the bars and then sanded the strip of aluminum with 400 grit sand paper until it measured approximately .4mm, which didn't take very long.

Then I wrapped the handlebar sleeve with the shim, and did a test fitting. You can do it just with the stem, though the photo below shows a test fit with both the bars and stem since I wanted to test the thickness as well. Most stems have a curve to the clamp area (to allow for installation). You want to maximize the contact area of the shim to the clamp area, but it's unsightly to have the shim extend beyond the stem. So, a little trimming is necessary.

http://i850.photobucket.com/albums/a...psogaubw8h.jpg

First I mark the excess area of the shim with a sharpie pen.

http://i850.photobucket.com/albums/a...psa3hfzelv.jpg

Then trim the excess first with some wire cutters.

http://i850.photobucket.com/albums/a...psfkdkmf3i.jpg

Then I used a circular sanding drum bit to remove the rest, along with another sanding with 600 grit paper to remove any burrs from the edge of the shim which might scratch the handlebars.

http://i850.photobucket.com/albums/a...pshqxdjs3n.jpg

Polish up those bars if they aren't anodized and install. I've used Nitto shims and cut up soda cans, but it's nice to have the clean lines and security of a good fitting shim.

http://i850.photobucket.com/albums/a...ps7axavmbk.jpg

http://i850.photobucket.com/albums/a...psmyucatyl.jpg

That's pretty slick work.

Sweet frame!

I had the same issue, 26.0 bar into that same 26.4 stem. I happened to be drinking a can of Guinness. Deed followed thought and the shim was installed before the last swallow cleared my throat. My handiwork is nowhere as tidy as yours.

I just make the shim oversize, then once everything is in place and tight, I take a sharp xacto blade and trace the edge of the stem. It's pretty easy to cut through a soda can with a sharp blade.

Someone's gotta say it.

Zen and the art of Shim Making