I'm working on a converting an older road bike to a fixed gear. The bottom bracket is in pretty good shape, but has a threaded spindle stud, so there's a nut that screws on to the spindle to hold the crank arms in place. On the drive side, everything worked out when I installed a single-speed crank that I had lying around, the chainline is even good.

On the left side, the recess in the crank arm doesn't leave enough space to screw the nut onto the spindle. I don't know why one crank arm fits and the other doesn't. I'm looking to buy a new crankset, anyway, but I want to make sure I get something that will fit on the spindle, since I'd like to keep the bottom bracket.

Any advice?

Deadblow hammer...

If you're planning to replace the crank, spend another 20 bucks and get a new bottom bracket to go with it. It's not worth the effort to try to make something fit.

Right, I realize a bottom bracket matched to my crank is ideal, but unfortunately I don't have the tools to remove this sort of bottom bracket. If I can find a crank that works, I'll go with that option over taking the bike into the shop. The bike came with old sugino cranks, so maybe a new sugino would work?

"Work"? Sure. Have a good chainline? Don't count on it.

Also, what kind of man ignores the opportunity to buy tools?