Anyone know what the clutch stall for a Yamaha kt100 with a four hole can should be? How do you figure out what your stall is using the mychron? Punch the gas and watch for the number that freezes on the tach just before you take off? Any help would be much appreciated
8600 to 8800 rpm. First read and understand the manual for your clutch. Then set it towards the low end of engagement. If the clutch is set for too high of an engagement, you’ll burn it up right away.
Setting the stall can be done on the stand or on the ground. On the stand, warm up the engine. A second person is usually required. Hold the brake and gas and read the stable rpm off the gauge. I wouldn’t hold the brake on for more that a few seconds as a great amount of heat will generated. Let the clutch cool before another attempt and while you are deciding the adjustment to make. If you’re alone, dump the session into Race Studio and review the data.
On the ground, get yourself a hundred feet of flat surface, gas it and watch the rpm’s.
Make adjustments in small increments. With an L&T, you’ll be close right out of the box. A Tomar will take a little more effort.
One low tech trick you can do to pick a stall point is to place a weighing scales between the kart and a wall and have the kart push on it.
Measure and compare your results, being careful to not burn up your clutch like Tony mentioned.
Thank you very much for the help guys! I recently went through and rebuilt my entire kart, it had been sitting for 3 years! I rebuilt the clutch and couldnt remember what stall speed i used to have or how to figure it out. I was at the track yesterday and the tach was reading 9400 at take off, luckily it started raining on my 2nd lap and i parked it for the day. Ill get the stall fixed and hopefully i didnt mess the clutch up.
Thanks again guys
9400 is no big deal, the range that Tony gave is just the ideal stall speed where you’re making the most torque usually. No need to park it if you’re over that. On the old pipe engines we were routinely running 10k RPM+ on our clutches.
Thank you TJ! Thats good to know!