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Jason wrote:In case you have not already, read up on dipping carbs and the jet block gasket.

I have not actually. I kind of wondered about the two safety torqs bits in the carb body and why they were there. I guess I will pull that off and check that gasket. I imagine there aren't many sources for the gasket since Kawi doesn't even show it in the parts diagrams.

You said you were going to clean the carb. Some dip the carb and damage the gasket. More a warning than a "you should check it".

Well I have dipped the carb in the past, two or three times, so it's certainly possible that it's damaged.

Oh wow. Break out the security torx.

jetsrus or sudco have the gasket, around $5, plus shipping

Jason wrote:Oh wow. Break out the security torx.

jetsrus or sudco have the gasket, around $5, plus shipping

Yup! Never dip a PWK carb!

I took the jet block off and took a look. Honestly the gasket doesn't look bad, but there is a bit of gunk around it. When I took the gasket off it came off in one piece. I'll probably still replace it. I still plan on dunking the carb with everything taken off as there is some varnish in the threaded holes for the jet block. After I have the new gasket in I'll make sure to not dunk it again.

From the pics, that O-ring looks like its smashed flat and not doing much. I would definitely replace it. Just because it isn't torn anywhere, doesn't mean its still thick enough to fill the groove.

Well got the new jet block o-ring installed and carb all cleaned. Put back in the bike and kicked her over. No change at all. Bike still backfires some and doesn't even remotely try to start. I tried removing the air filter just to ensure I didn't have an airflow problem. No change.

Again I've checked compression and it's good, around 150 PSI.
Checked spark and it's strong.
Clean carburetor with new jet block o-rings.
Air filter clean.
Brand new reeds and old ones looked fine.

I'm frustrated to say the least.

Thanks for the report.

Any chance of a clogged spark arrestor / silencer?

I feel this would be highly unlikely. I replaced both the pipe and silencer with FMF goodies when I bought the bike a few years back. I'm still leaning towards a timing issue of some sort, but that's only because I have no clue.

Well I pulled my magneto back off and tried adjusting the timing. I previously had it fulled retarded, so I went fully advanced. No changes. The first time I put the new stator in I had it in the center so I know that didn't work. Woodruff key looks fine.

I then figured I'd try putting fuel in the cylinder to see if it would pop off - nothing.

I still can't wrap my head around why it started after getting home, but hasn't started since.

Just a thought...

I've only had 2 strokes bog out and quit when the top end is fried. More than once through the years. That being said, I have no idea how you could have restarted it...or how it could have compression unless the crank-case vent is possibly clogged.

This is an interesting one. I'll be standing by for someone smarter than me to come up with a solution.

Fuel, air, fire...something is not cooperating.

that sure sounded like fuel starvation to me.

normally if it runs out slowly (out of fuel) it will increase in idle until it quits (dead).

but that sounded like fuel stopped flowing, or something rattled around in the exhaust and plugged it. check your silencer for a broken tube, rats nest, similar.

oh yes, make sure you have a clean air filter on there.

I'll go out in the garage later and see if there is anything visible in the exhaust. Where is the crankcase vent on this bike?

One thing I haven't mentioned before is that when trying to start the bike, after a few kicks, I can see smoke coming out of the exhaust. By smoke I would say normal 2 stroke exhaust color. I can also see it coming out of the cylinder if I pull the spark plug out after kicking.

That video sure looks like you have a fuel delivery problem, along with your description of seeing smoke when kicking but the bike doesn't fire. If you are still getting spark then fuel delivery has to be suspect. I never saw where you said what jets you have installed, and whether any top end work was done. Also haven't seen anywhere where you removed the tank and petcock and made sure everything there was clear as suggested earlier.

have an RMX that wouldn't start unless bumped on warm days and then smoked like hell...would run for a bit then die...turned out the PO had some crazy jets in there and had reassembled the powervalve incorrectly and installed the piston backwards. Like B737driver said...fuel, air, spark...if you have two then you know which one is likely missing.

bufftester wrote:That video sure looks like you have a fuel delivery problem, along with your description of seeing smoke when kicking but the bike doesn't fire. If you are still getting spark then fuel delivery has to be suspect. I never saw where you said what jets you have installed, and whether any top end work was done. Also haven't seen anywhere where you removed the tank and petcock and made sure everything there was clear as suggested earlier.

have an RMX that wouldn't start unless bumped on warm days and then smoked like hell...would run for a bit then die...turned out the PO had some crazy jets in there and had reassembled the powervalve incorrectly and installed the piston backwards. Like B737driver said...fuel, air, spark...if you have two then you know which one is likely missing.

As far as jets go I would have to look as I don't remember exact numbers, but I think I'm running the factory pilot jet(45 or 48) and 152 main I believe. Needle is a R1173N in middle slot. Air screw is currently 1 1/2 turns out.

The only top end work I've performed was replacing the power valves a couple years ago as they were all paper weights. Also replaced the gaskets while in there. I did not replace the piston as it and the cylinder appeared fine.

I have not removed petcock to inspect, but when turning valve to either on or res fuel flows out of the line quickly.

Perhaps I'm jetted too rich on my pilot circuit? Starting the bike has never been an issue before though, and the plug has a dark brown color to it when riding properly.

I've also tried various settings on the idle screw, all the way in, all the way out, a few turns out. Makes no difference.

Does turning the air screw make any difference? If not it's a jetting or carb issue. Proper plug color should be a light tan. Hoping you find some resolution soon.

I haven't really messed with the air screw too much yet. I know before I cleaned the carb this last time I had it one turn out, I believe. I'm curious if I should try a smaller pilot screw to see if it changes anything, but I can't imagine it would since this has only know become an issue.