In this case the belt did not effect the precision because of how the Sioux machine is designed. These valves were measured and are true with runout that is better than factory. The grinder shaft is designed with tight tolerances that utilize pressed interference bearings, the noise you hear is from the tensioner, not the shaft. If the precision were compromised it would show in the measurements. You will be happy to know there is a new belt on the machine and it is now quiet.
Thanks for the demo.
Glad you liked it.
You lost me at the belt moment. Grinding is a precise balanced job.
In this case the belt did not effect the precision because of how the Sioux machine is designed. These valves were measured and are true with runout that is better than factory. The grinder shaft is designed with tight tolerances that utilize pressed interference bearings, the noise you hear is from the tensioner, not the shaft. If the precision were compromised it would show in the measurements. You will be happy to know there is a new belt on the machine and it is now quiet.