I have a Tc88 on my bike and I measured the old belt it is 5/8" thick and I'm getting 27 3/4" around the belt. I have a comet belt chart to look at but the closest measurement on the chart to what I'm getting off my old belt is 27 3/8". So my question is over time would it be possible for a 27 3/8" belt to stretch out to a 27 3/4" or do i have some odd setup and need some special belt, or should I go ahead and get the 27 3/8" belt.