Technique for Checking Clutch Engagment RPM for 206

New guy question here… Been out of the game for a couple decades now and I am trying to figure out the proper technique for testing the clutch engement. When I check it like I used to back in the day (damn I sound old) it comes in consistently 1k higher than the spring setup chart says it should (4400RPM, Hilliard Flame, 2 whites and a black). I mostly ran Yamaha back in the wet clutch days and when we checked it, I’d be on the ground, wack the throttle, it would launch, the RPM would stabalize for second before it started climbing, and thats your number. When I try the same technique, the numbers come in what I would think are high.

Before I decided to ask here, I kinda went down the rabbit hole and saw refferences to engagement RPM being separate from full lock RPM (which I was apparently measuring), but no real info of how to check the “engagment RPM”. So my ultimate question is; am I doing this wrong or do I perhaps have an issue that needs to be sorted or maybe I just need to tune the damn thing?

For background, the clutch is used, but I cleaned it all up and rebuilt it, It all seems to be in good shape, and I am fairly confident its assembled correctly. That being said, the shoes are flipped I believe, so that the skinny end, or taper of the teardrop is leading. It came that way and I left it. I am not sure if this is standard, for the wording on shoe orientation from Hilliard confused the hell out of me…

Any help, techniques or insight would be awesome.


Never though about checking the Engagement RPM.

Here is a link for the installation, leading is what I preferred if you are running it outboard. Trailing if inboard. You can also face the tail to each other which is not recommended, but it will give you a very hard engage.

Ultimately I think the engagement RPM does not matter too much since it should not disengaged during the runs. If you are doing standing start, simple a stopwatch should be able to show you the difference.

People say that a lot. At our track you are on the clutch about 8 out of 40 seconds. I determine clutch engagement by looking at where clutch holds during lap in the session. It typically is very close to what the chart says

Where do you race that you are on the clutch for 8 of 40 seconds?

Gateway Kartplex near St. Louis, MO. On Mychron I look for how long the RPM is at about 4100 , but kart is accelerating. It is in the 8+ second range

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Makes sense. Some layouts at gateway are tight. FWIW, I would never slip a 206 at 4100. You’re giving up a lot of peak torque.

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Thanks. It does occure to me now that is higher than I got with 4 black last year. I need to look into that

I run 2 black and 2 white springs on my clutch with no weights.