Excentric Front Derailleur Shim

prusaprinters

<p>Front derailleur mounts are often oversized for the seat tube of your bike, and the shims provided to make them fit are concentric. This might be OK, but often isn't: Sometimes, you need to move a front derailleur inboard or outboard to get shifting to work well, beyond the range that the limit screws may offer. (For recumbents, for instance, the cage may hang up on the boom tube when it's inward, meaning the downshift into the smallest ring may not work reliably.)</p><p>These excentric shims let you tweak the position by changing the relationship of the non-concentric circles – the interior and exterior. They have a lip on top to sit on the clamp and make installation easier.</p><p>I've made them to bridge the gap from a 28mm tube to a 35mm derailleur clamp, a 28 to 32, and a 32 to 35. I use the 28 to 32 version on many bikes with great success.</p><p>If for some reason these can't push the derailleur out for you, check out my model for bottom bracket spacers.</p>