Brake lever clamp too loose for handlebars I'm trying to attach a new brake lever onto my handlebars, however, the clamp (circular part) of the brake lever that slides onto the handlebars is a bit too loose. I've tried to tighten it but because it's entirely made of metal, the clamp doesn't tighten much on the handlebars. Right now I haven't put the grips on my handlebars yet. How do I resolve this problem? Will putting a roll of handlebar grip between the handlebars and the brake clamp help secure the clamp? Thanks.
Normal aluminum cans are basically .1mm thick, so a wrap gives you .2mm. Most of the smaller scale clamp diameter discrepancies, say from a tolerance problem or from a mismatch like a 26.0 aux lever on a 25.4 clamp area, one encounters clamping controls and acessories on to bars can be resolved with aluminum can shims, or stacks of them. Going up to putting a 23.8 aux lever on a 22.2 section with them gets dicier; other kinds of shim stock will work better, but even there putting 8 layers of can on is probably fine. As long as your shim material is metal and as long as the finished product doesn't slip readily, it's probably fine. Fiber grip/carbon prep can lend a lot of solidity to such hacks.

Use scissors and math to prepare the shims. Don't cut yourself.