I have two sets for my bikes. Short and medium length for the RS series carbs. I never used them on the track because:
1. NO FILTER on these.
2. I ain't good enough to bother. The extra gains I would get from those wouldn't really help me. I need more track time to get my laptimes down, not HPs.
3. My motors weren't in a high-enough state of tune for those to do any good anyway. They would just burn up my valves faster.
Maybe one day I'll build a motor that they will be good for . . . :mrgreen:
I used them on the street ONCE. That was when I was running a real high-compression motor that had been in storage for a LONG time, and I needed to shoot some ether in the intakes to get her to fire. Once I got the motor running good, then I put the filters back on.