Significant, yes, if you're heading for a checker'd flag. Actually it'd be morelike 2° at the crank, methinks... anyhow: there isn't much to be done about it without going to offset keys or a fully adjustable cog. Tons o' bucks for a small deviation. Frankly, fitting new cogs, tensioner and chain should have it well within factory tol's. Offset keys if ya just GOTTA get closer. If you're really anal, get out th' ol' wally and get the vernier cog. They ARE really sexy. /ubbthreads/images/graemlins/angel.gif