Dust Cap Crank Arm
 

I went to unscrew the dust cap from a mid-eighties Bianchi, ofmega crank arm and it didn't budge. I had a large screw driver that I slipped into the slot. It didn't budge. I don't want to ruin the cap. The slot in the cap is "S-shaped". Does it require another tool? I have no clue. Thanks

Lay the bike on its side and drip some Liquid Wrench or similar product around the cap. Let it sit, and repeat. After a few hours or overnight use a brass drift or short wood dowel and a hammer to lightly tap around the outer edge of the cap. Give solid taps but not hard enough to dent the cap. This should shock the threads loose. It should then come out using a large flat blade screwdriver or whatever tool that will fit.

S-shaped? Are you sure? Picture?

I'll give the liquid wrench a try. Thanks

If it's a plastic cap, just break it off in pieces from the inside out.

No, it's metal and I'm trying not to chip the chrome plating.