KATOOMS+KEIHIN

[Rain Man]

I'm looking for suggestions here.  I got a 1996 KTM 360 EXC and it has a peculiar problem when you croud the motor, especially over woops, jumps, rocky terrain and WFO conditions. This bike wants to do 22 mph,   period.
 If I crank it through all 5 gears WFO, and just  try to "cruise" with it,(fire road type of speed)you'd think ya needed a bullet proof vest, around your legs, Kapring kapring kapring,    I never, ever heard a 2 stroke like this.    been through this with a few people up North and just about tried every Yankee ingenuity idea up  heaar. Are Keihins just weird, the exhaust valves weird , or is a Mikuni the answer??  The bike runs terrific, at 22 mph.
rain man.[?][?]

[Rocket]

Raymond
Keihins are very good carbs.  Should not have a problem with them. Have you pulled the carb off and made sure that it is clean? Check the reeds when you pull the carb off.  Do you have a clean air filter?  No rag stuck in the airbox?  Possibly you have an ignition problem.  Check the timing.  You would have to remove the flywheel to see where the marks line up for this.  Does it start running like this right away or does the motor have to warm up?  If it only runs bad when the motor is hot, could be the stator.  Check your silencer, make sure it is not plugged.  Even if the power valve was stuck, I would think you could go faster than 22 mph.  
Good luck,
Rocket

[Rain Man]

I guess its gonna be near impossible to bench test this on the forum, It sounds like it momentarily runs out of fuel after going through some real rough sections under heavy throttle. It could be timing, its been checked,  its dead on.  After using this bike for 7 years, i'm starting to believe thats the way it sounds. And most riders say it sounds great?? You have to be on the bike to experience the pinging  sound I'm hearing. weird  R

[tmc3c]

Rain Man, I am with Rod on this one, I belive if you clean the carb "JETS" you will find a new bike that will fly!! Are you running race fuel?

Thomas Carmichael

[Rain Man]

I've had the carb and jets out a dozen times.  I've tried leaner, richer, up with the needle, down with the needle, diffeerent tapers,  High octane race fuel (105) MIXED WITH 93, tried 87 octane, Differ ent brands of synthetic,
     oil on the filter, no oil on the filter. Its a continous lab experiment with that displacement.    It does it when your in hi rpm ranges, and wow, when you let off @ hi RPM's.  
     I almost suspect the float circut,   particularly the needle, That,  reason being, some times you got to lay down the bike momentarily to start it when its cold.(And its sometimes 32' out when we ride)   But I've ridden with a dozen other Katoom riders and some times, thats the only way they'll start too!!.  But mines the only one that Kaprings when you let off the gas @ high RPM's. It just hates to do anything but chug chug chug along, weird  
 Raymond

[SCOTT CURTIS]

Try replacing the exhaust springs.  My 380 made pinging type sounds, turns out the springs were fatigued.  Noise went away once I replaced the springs.

[Rain Man]

Scott, its funny you mention that, I notice every time I fire this race bike up it blows all kinds of smoke outta the front of the bike (exhaust port).  I'm kinda thinking that maybe the exhaust packing is creating to much back pressure, and when you get the thing revved up and under load, its not allowing enough err breathing room?  Or possibly keeping to much heat in the port.??  Good suggestion
  R