I'm using an Utegra double crankset for my fixie. I want to remove for large chainring, but now the bolt used to hold the smaller chainring to the crank is too long. I was thinking about using some washers to take up the slack of the missing big chainring, but wasn't sure if this was an good idea? Does anybody know where I can get a short nut and bolt? Or is it safe to just use washers in place of where the big ring used to be?