I’d guess that the karts you raced we’re very close to the slipping point a lot?
I can imagine that in road racing with those big gears in laydowns with axle clutches, the stall speed is pretty high and the slip is lonnnnnnng.
TaG should not be disengaging unless you lock the wheels or brake hard enough with tire slip to drop below the engagement speed which is something like 6500 I think.
If you have an RPM trace I’d be interested to see it.
On an engine like a Yamaha Pipe where the clutch slips at like 11k, then it unlocks the clutch pretty quick when you lift even at high-speed.
On a KA or X30 where the clutch engages at like 5k, it never disengages. Unless you do a big lock up.
I don’t know shit about 206 clutches.
And there it goes . . . Squirrel!
A 206 thread and now you bring up TAG and shifters. 
They are just shitty shoe/drum clutches that people also use on yard karts.
A lot of text for a short simple subject- after reading everyone’s 2 cents worth- heres mine…
1.Shoes are engaged because of physics- plain and simple- wherever the inertia is from… motor running, motor not running, weights or no weights…(see rpm chart for more or less)…
- Hilliard clutches- the choice for almost all racers it seems- due to their simplicity and economics and effectiveness- are not shitty yard kart clutches…
My son in a Briggs World Formula would keep up with some of the TAGs (two stroke) engine karts in Sandia Speedway NM with this “shitty yard” clutch…
Oops - forgot to add that weights would help with standing starts- engage faster and maybe less slippage…. once again- my 2 cents…
What setup would you use for a rolling start? And how often do you replace the springs?
Never done rolling starting before. Depends on you gearing, I would assume you clutch will be already locked at rolling start speed, so clutch setup will probably make too much differences.
I usually rebuild the clutch middle of the season, new shoe, new spring.
You should set your clutch up for slowest rolling speed. You want it to stay locked up the entire race, including the rolling start. Pretty easy to look at and set. We started racing at 3400 with no weights, eventually we set ours up for 3000 rpm with 8 of the heavy weights on the clutch and never changed it again.
From what I have found online, factory 206 motors make peak torque (11.13lbf*ft) at 2,500 rpm. What’s the justification for ever allowing slip beyond that? Every person I have asked that question has responded “that would bog the motor”, but the dyno bogged the motor, too, and made more torque because of it. Slip won’t ever give you more torque, just more heat into the clutch, since you are going to higher rpm where the engine makes less torque.
Unless you have a hotter motor that makes more torque at higher rpm, it seems like a 4-stroke at 2,500 rpm just sounds bogged.
That stock torque curve from briggs is a bit misleading. It is very flat back to that far, but not peak. Peak is 3100-3400 depending on your carb/head/tune/engine. You get just a little on the backside of that curve and it WILL bog. That is why the old timers always tell you to set it a couple hundred rpm ABOVE peak torque. Give you some wiggle room for these crappy clutches.
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Why we landed at 3000 engagement. Lock up is a 200 or so above engagement. Trying to put the clutch right in the sweet spot and still just below our lowest RPM.