The hole closest to the pivot bolt controls rpms closer to engagement. The middle, more for middle speed and the tip more for high speed. Not talking engine speed, talking track speed.
Start by checking engagement rpm and rpms at 10-15 mph. If the rpm is too high then add weight near the pivot bolt hole (heel) Now climb a hill at full throttle, steep enough that your track speed is about 1/2 of the sleds full speed. Here your clutch should be 1/2 open and the middle magnets will have most influence. If rpm is high, add more weight to the middle hole. If low remove some weight. Now at full speed (clutch shifted out) check the rpms. If high, add weight to the tip. If low remove some weight.
Keep in mind all weights contribute at all speeds so you will have to go back and forth to have proper rpms at all speed. start with equal weights spread out and total weight equal to stock weights.
Many guys make the mistake of changing weights to correct RPM,s without considering the position the clutch was in when the RPM's were off spec. You can't look under the hood while riding to see how far your clutch is open so look at your track speed and figure it out. Most sleds will do 80 mph unloaded and at full clutch shift. Expect 40 mph at 1/2 shift. You can also calculate your top speed if you know your engine rpm, clutch shift ration and gearing, along with driver size.
Start by checking engagement rpm and rpms at 10-15 mph. If the rpm is too high then add weight near the pivot bolt hole (heel) Now climb a hill at full throttle, steep enough that your track speed is about 1/2 of the sleds full speed. Here your clutch should be 1/2 open and the middle magnets will have most influence. If rpm is high, add more weight to the middle hole. If low remove some weight. Now at full speed (clutch shifted out) check the rpms. If high, add weight to the tip. If low remove some weight.
Keep in mind all weights contribute at all speeds so you will have to go back and forth to have proper rpms at all speed. start with equal weights spread out and total weight equal to stock weights.
Many guys make the mistake of changing weights to correct RPM,s without considering the position the clutch was in when the RPM's were off spec. You can't look under the hood while riding to see how far your clutch is open so look at your track speed and figure it out. Most sleds will do 80 mph unloaded and at full clutch shift. Expect 40 mph at 1/2 shift. You can also calculate your top speed if you know your engine rpm, clutch shift ration and gearing, along with driver size.
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