Grinding and drilling a rim tip
If you feel that you aren't getting enough brake performance you can always grind your rim. the way to do this is to take the tyre off the rim and secure the rim in some thing. Then you can either take an angle grinder and roughen the rim up or you can take the neater option and mark out dots on the sidewall each 1 cm apart and then take a rough large flat file and with the edge put slots into the rim about 1mm deep. do this diagonaly around both side of the rim. the grinder option works slightly better but wears the pads and the rim down extremely quickly and doesn't look very neat.
drilling a rim
If you feel your bike is too heavy you can always save a little weight by drilling your rims. To do this take the tyre off the rim and find ametal drill bit to drill through the rim. drill a hole betweenm each spoke (use a maximum drill bit size of 10 mm as any bigger will weeken the rim substantialy and do not drill the weld in the rim or it will snap) and make sure that after you have drilled you get rid of all metal shavings so you dont get loads of punctures. It always pays to be safe and run two layers of rim tape.
WARNING!:
Drilling a rim voids the warranty so dont say i didn't tell you! also do not drill your rear rim if you are a very heavy rider unless you expect it not to last
