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Buttoned up the bike after taking the carb apart to replace the jet block gasket. The bike was difficult to jet and I figured that $4.41 was a cheap price to pay to eliminate a reportedly problematic part. Cleaned the carb and reset float height whilst I was in there.

Other jobs whilst the bike was apart were a new throttle cable and repacking the exhaust with new 2 stroke packing.

First, the good news:
Fired the up and took it for a spin around the neighborhood. Wow..!! The jet block gasket was definitely an issue.The jetting is so much better now. No spluttering in the mid range, and careful throttle is needed to keep the front wheel down. :)

Now, the bad news:
Pulled the circular cap from the left side (as you sit on the bike) and watched the KIPS gear whilst the engine was revved. It did not move at all. It appears to be stuck in the open position judging by YouTube videos I've seen. Without tearing it down I don't know if it's stuck or broken at this point. :(

things to check:
the pin on the kips arm, in the right side case
the pawl on the vertical shaft
after that, might as well pull the cylinder and make sure. it only takes a new head and base gasket to do it, and about four hours work the first time

Thanks for the tips.

I edited my first post, as it was the left side circular KIPS cover (as you sit on the bike) that I removed and saw no movement as the bike was revved.

I took ohgood's advice and check the KIPS arm and pawl gear on the right side. The pawl gear is not damaged. The KIPS shaft arm also does not appear damaged. Moving by hand there is very limited movement. I can peak through the exhaust port and see small movement from the main KIPS valve and the 2 sub valves when I wiggle by hand. I am now wondering if maybe the issue lies inside the right engine case where the exhaust timing valve sits.

Davenay67 wrote:Thanks for the tips.

I edited my first post, as it was the left side circular KIPS cover (as you sit on the bike) that I removed and saw no movement as the bike was revved.

I took ohgood's advice and check the KIPS arm and pawl gear on the right side. The pawl gear is not damaged. The KIPS shaft arm also does not appear damaged. Moving by hand there is very limited movement. I can peak through the exhaust port and see small movement from the main KIPS valve and the 2 sub valves when I wiggle by hand. I am now wondering if maybe the issue lies inside the right engine case where the exhaust timing valve sits.

the kips assembly in hte right side of the engine will provide a decent amount of resistance to movement. i would not force that myself.

i would pull hte cylinder and inspect/clean the kips sub valves, horizontal shaft (front of the engine) and get the grit/spooge/carbon off those pieces. that makes huge difference to how smoothly the assembly works together. two stroke oil or grease on the seals (horizontal shaft) helps a lot too while reassembling. occasionally it might not be a bad idea to slather those seals with two stroke oil to prevent carbon build up between yearly cleanings.

More great advice.

I can't wait to tackle this stuff head on, but time is not on my side right now. This weekend is already looking pretty shot. The car needs new rear brakes, kids have sports and parties, and I have a full day Sunday for classroom re certification for the new T-RCP for my MSF RiderCoach. Mid-week ain't much better.

Anyway, whining aside. My current thinking is that I need to take the cylinder off and also take the inner clutch cover off. After removing the 'claw' gear from the KIPS actuator shaft I see that the KIPS valves in the head are stuck/gummed up. So a definite strip down and clean is in order there, hopefully no broken parts in that assembly.

The reason I also think I need to remove the inner clutch cover is to inspect the KIPS actuator mechanism. With the 'claw' gear remove the KIPS actuator shaft now spins freely. It won't spin complete circles, but it will turn with about 270 degrees of rotation. Is this correct? I was expecting this would be linked to the KIPS actuator mechanism and not spin freely at all. I am wondering if the stuck KIPS valves may have busted the pin on the bottom of the KIPS actuator rod?

Just to make sure, you were revving the engine enough for the kips to actually open correct? If I remember right it is up around 5000 rpms when it starts to move.

I absolutely was. Not a flicker from the KIPS. Dead.

After taking the inner clutch case off I know why....busted pin. Which was probably caused by the KIPS valves which are stuck / broken/ gummed up. Next job is to remove the head and inspect the KIPS valves.

So, the reason the KIPS valves were jammed is because a bolt (top left corner of the photo below) had fallen out and wedged itself in the works. With the bolt removed the valves are smooth as butter. Next step is to remove and clean the KIPS valves and rebuild the bike. Only new part is the KIPS governor pin and new gaskets.