I use slowers info on clutch tuning and it has help me come a long way ,i use a sno-mo spring tension guage to measure primary spring tension,and my gram scale to measure finger weight.Its all about being consistant ,the biggest variable in racing is the rider so anything to help that variable is needed like launch limiter,shift lite/tach.To make adjustments to the clutch for a certain track all other variables must be constant,i adjust the clutch on my shee just like a drag bike(street bike).Each motor will be diffrent i now have diffrent set ups ready for diffrent track in seperate bags,the biggest time improvements came to me with clutch tuning