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The issues come first. I fully cleaned, checked and rebuilt the carb. I cleaned and re-oiled the air filter. I changed the engine oil and put new fuel in. It will clutch start easily but refuses to kick start. When its running it will run hard upto 3/4 throttle where it just bogs down, let the throttle back to 3/4 and it runs fine. I looked under the rubber boot on the actuator rod (I think it's called) EDIT *** (its a governor shaft sp?) and when it's revved up the rod trieds to turn but can't and thats when it starts to break down and rev crappy. Would a faulty power valve stop the engine from kick starting (even though it will readily clutch start) ??

OK here's the pics.

The right side engine cover (the blue one) is the K.I.P.S. power valve system. I assume you have already looked at the diagram to see the two subvalves which are pretty similar to the other KDX's since these first ones with the K.I.P.S.

If it is not coming out at around 6,000 RPM, then it may be clogged with carbon. The right side does not have a gasket under the cover, but the left side does. Anyway, I don't think that would cause it to not crank.

How long are you letting it warm up/run before giving it full throttle? Can you QUICKLY give it full throttle before the KIPS comes into play and let off??

Did you remove the float valve assembly in the carb? How was it?

Have you tried to crank it with the fuel petcock only open part of the way, or to leave it open, shut it, leave it open, etc. to try to limit how much fuel goes into the bowl?

Was the previous owner ashamed of the battery??

I am glad to see an air-cooled KDX on here. Dave04 and Big Al should be proud.

Jason wrote:
How long are you letting it warm up/run before giving it full throttle? Can you QUICKLY give it full throttle before the KIPS comes into play and let off??

Did you remove the float valve assembly in the carb? How was it?

Have you tried to crank it with the fuel petcock only open part of the way, or to leave it open, shut it, leave it open, etc. to try to limit how much fuel goes into the bowl?

Was the previous owner ashamed of the battery??

1. 5 minutes and it will bog with a WOT wick no matter how warm.

2. Sure did (thanks to your advice) and all looked sweet, no grooves or dirt.

3. No I haven't tried the on / off trick. Wouldn't it be evident if the bowl was over filling by the overflow tube ?? Please excuse my ignorance.

OH BTW he is looking for a power pipe to suit it, I told him DG are probably the only ones available but good luck finding one over here. Either that or I told him to re-paint it in high heat black gloss.

Just one other thing, if the exhaust valves are closed when the should be open or vica versa will it still start without an issue. And I thought I had the starting problems pin pointed.

Oh just ONE other thing. The clutch on this bike can't be pulled in unless the engine is running. Whats the go there, anyone ?? Weird stuff if ya ask me...

3. You sound correct on it overflowing. Keep in mind what kind of person you are dealing with.

As far as a pipe, FMF may be the best. DG makes one, too. DMC MADE one, but do not any longer. That guy must have changed his game when I was not riding for a ffew years.

I don't think the exhaust subvalves beintg opened or closed would affect starting too much.

I see you are in my "clutch drag" thread, so maybe you will find an answer there. I am waiting for SkiPro"fessor"3 to start clutch school again. Maybe it has a notched basket??

I was unaware FMF made them, thanks. Hey how much does the 87's tank hold ?? The bike looks pregnant with that huge tank.

The FMF pipe was the biggest power modification I ever made to my '87.

I think the tank holds 3.2 gallons.

I bought the DG pipe and silencer for my 88 in Feb 04. They had one more on the shelf and sales guy was not sure if they were going to make more That pipe and silencer made the 88 rip! It smoked my 04 when the 04 was in stock form.

I just checked yesterday about tank size 3.3 gallons according to manual. That big tank is great for long rides.


Good to see another C model.

I'll try and find a few minutes today and post a couple of things I have found concerning the power valves. I'm at work, best not anger the man

Your a champion, I'd appreciate any help you can offer.

Ok, lunch time....

My 88 and my 86 both had issues with the power valves gumming up over time making the actuator unable to open and close them. It sounds like you have removed the R/S cover located about the rubber boot. (yours is blue) . Inside the cover there is a linkage that is attached to the shaft coming from the engine case (inside the boot)
The linkage is attached by one bolt. when you remove the linkage you should be able to move the end of the power valve shaft freely in and out. The travel on the shaft is about 1" total. If it is hard to move in and out or is stuck fully in or out you will have to remove the head to remove the valves and shaft. Its not a hard job. Just keep track of which valve goes on the right and left side. The valves also have a small punch mark on them. Make a note of where the marks are when you take the valves out. If the valves are very gummed and full of carbon they can be very difficult to remove. A little WD-40 sprayed in the power valve bore helps. . I have done this 15 times. I'll be glad to help if you have questions.

Thanks Dave. I've done the P/V on my H model without any problems whatsoever so fingers crossed it will be the same outcome when I get into the 87. Again thanks Dave and Jason for all your help, I totally appreciate it... Trev...

You're welcome! Good luck with it!!

You're welcome Trev. Good luck with the C Model. I wish I still had mine
Maybe I need to start working on my brother to sell it back to me.

Cheers fellas. I've since found out its apparantly an enduro tank. She's a whopper.

OK well the P/V shaft moves freely out about an inch like stated above by Dave. The valves seem to be timed fine. I now beleive its somewhere under the clutch cover causing the problems. Any advice about the exhaust advancer assembly (I think its called) and clutch would be a great help. Also with the head off should the piston have some play inside the bore ?? By "some play" I mean about 1-2mm. Cheers guys...

KAY DEE EXER wrote:OK well the P/V shaft moves freely out about an inch like stated above by Dave. The valves seem to be timed fine. I now beleive its somewhere under the clutch cover causing the problems. Any advice about the exhaust advancer assembly (I think its called) and clutch would be a great help. Also with the head off should the piston have some play inside the bore ?? By "some play" I mean about 1-2mm. Cheers guys...

1 -2 mm of play?! Surely, my good friend, you are in great need of sleep. Take a nap and report back.

I'm not joking. It moves around inside the bore more than I feel it should. It jiggles from side to side. If you push on the piston in circular motions it rolls around inside the bore. I hope it makes sense. Whaddaya think regarding the KIPS assembly being all free and good ?? Could it be the advancer assembly ?? Have you had one apart or are you familiar with its workings ??

make a movie of the piston slop. That should be good to see. I bet Jason would like to see that!!

OK well I haven't slept yet but the piston slop is around 1mm maybe less.