I think both of you are correct the sprocket was warm and I am sure it did enlarge a little and I am sure the belt had some physical change to it. I never check my belt before to see if it got tighter. The only reason I adjust the belt was because I change the rear tire, so I thought it would be a good idea to adjust it. Also the manual says to. Thanks for all your help.

 

Yeah, I tend to get a bit "poetic" too at times

Belt does get tighter but it is not just the belt you are dealing with.

 

Careful...not all belts are equal. Kevlar, my friend, does not expand when heated. But you are definitely correct that the pulleys contribute.

 

Never said that the belts expanded. Once again, read all befor ------!

 

Nor did I say that you did. I was merely commenting on the fact that belts can be made of different materials which can behave in different manners.
"read all befor"--------