Bodged a nice 48/38/28 chainset onto my Cannondale road bike to allow me to enjoy the steep local hills rather than half-killing myself using its original 53/39. (The bodging was having to make the double front mech work for the triple by filling a tab down, and I also had to add a shim under the 'b-screw' to get enough movement of the rear mech to stop a rumbling in the biggest 2 sprockets.)
I also wanted lower gears on my Cannondale CX bike so I replaced its 36 inner ring with a 34, and put a 12-36 (or was it 11-36?) cassette on to replace the original 12-30 (or was it 11-30?). I had to put a MTB rear mech on to cope with the big sprocket. The bodge was that a
9-speed MTB mech has a compatible pull-ratio for the bikes'
10-speed shifter!
A couple of singlespeed bodges ...
I took a couple of old cassettes to bits and used one of the sprockets at the back, plus a pile of spacers to hold it in place. By carefully selecting the number of spacers either side of the sprocket, I got a perfect chainline.
The chain tensioner shown (as supplied) pulls the chain down to tension it. It uses a spring to create the tension. I found that the tensioner arm bounced about on rough roads and I kept unshipping the chain. I bodged it by removing the spring so that I could use the tensioner to push the chain up instead. I added a thick washer on the mounting bolt which allowed me to adjust the tension manually and then tighten the tensioner in that position.