well richard, i checked with my local auto body supply shop expert and he advises me that you should look at 2500-2700 obm. any faster and you risk burning the paint or removing it with the abrasive. tread carefully. mike 86 5kcdtq 82 lada 1600 with momo Cyclops Bicycles Ph. (604) 545-5644 Fax (604) 545-1167 michael_mulholland@mindlink.bc.ca