KDXRIDER.NET

Hey Everyone,

TLDR, pics below... Got back from my ride last weekend and noticed a lot of black oil mess around the exhaust / KIPS cover, dug into it tonight to find the source.
- Couple of things about the bike, it's a 1996 KDX 200 that I picked up around 2009.
- - Rebuilt the top end about 10 years ago, haven't done much riding until say the last 12 months (kids, life, etc). Maybe has 40 hours on it now
- - I keep the carb pretty clean, but have never jetted (stock, ran 32:1 for a while to bed in the piston / rings, most of the time now run 50:1 amsoil dominator but I know I'm running rich since I didn't jet the carb)
- - Maybe it's time for a new pipe? Stock pipe / resonator has been on the bike since I got it... is the spooge just finally coming back into the engine? Is there a good method to clean that out?
- - Never jetted because I don't really have a place to do the chop test... Maybe it's time to just man up and do it?


Any ideas where this is coming from? My parts list so far:
- Copper exhaust ring, o-rings for pipe (maybe new pipe?)
- gasket for KIPS cover
- clean everything up, put back together, call it good?

Let me know what you all think. Bike has been dropped a few times, no super hard hits on the pipe but good lord bike is 25 years old so it's had some hits. Didn't really notice it leaking like this until now though.. Maybe it's just finally tweaked enough where it matters?
- Our last ride was mostly single track in michigan, but we got slowed down a lot by storm damage (lots of trees down, etc), so we had to rip it back on dirt roads to the parking lot... Maybe just finally put enough high speed running where this became an issue?

Anyway, if a new pipe / jetting is the suggestion... Any suggestions on parts? I would guess gnarly woods and turbine core for the riding I do? Any thoughts on michigan's spark arrestor requirements?

Thanks in advance!

It's difficult to tell from that plug but the electrode part of it looks light brown to me? indicating the jetting might not be too bad and all that gunk might just be years of build up and no servicing of the PV.

Issues you may have given the age and lack of running and could be worth working through:

1. Fuel. Drain any old fuel from the tank and carb and put fresh stuff in.
2. PV clean. given its age, if it hasn't been serviced in awhile it's well likely the PV system is really full of carbon and needs a good clean. i'd say thats the case with your bike.
3. Excessive spooge leaking like that is often due to leaky o-rings at pipe/cylinder. If that carbon/gum was inside of the PV cover then you may have leaking PV seals and you should replace those. on each side of the PV shaft there is a seal pressed into the cylinder.
4. Coolant - got any loss of coolant? that stuff looks rather liquid - give it a sniff make sure its just fuel.

People advocate for plug chops but if you dont have capacity to do it, like a lot of people, there are some pretty good ballpark jetting figures available online that you can use. provided you adjust slightly for any altitude difference you should get jetting within a reasonable range. i really dont think a plug chop is necessary to get a decent base line level of jetting.

Looks like a typical KDX run at 32:1 and not cleaned regularly. Probably got it dripping from the pipe/silencer junction and from the end of the silencer. Needs a good cleaning, new plug, and go ride.

Thanks Buff & Tucker. Spent another hour or 2 on it tonight and basically got it prepped to pull the engine.

I'll open up the KIPS, maybe try and keep the head on it if I can but otherwise pull the head, check the jug, etc etc.

As far as the health questions:
- no coolant loss
- Have been running fresh gas in it all year. I keep the carb pretty clean / check it regularly but hadn't checked the KIPS since it's a "600mi" maintenance item... realistically it sounds like I should probably just do it annually.
- definitely need to clean out the silencer / expansion chamber, so I'll give those a good cleaning while I have everything else apart... the manual says to pull the drain plug on the silencer with the engine running so I'll give that a shot when I get it back together too.

thanks everyone!

If you pull that drain plug, have a rag under it, you will paint everything black if you don't

Ha thanks Buff, I'm going the long route. Decided to just rip it all apart so I can give everything a proper cleaning. Piston, Cylinder, all look like they're in great shape, so at this point it's a spooge clean up.

Going to order gaskets, etc, clean out the pipe and silencer, replace some seals while I have it all apart and then put it back together.

Does anyone have a method to get the KIPS shaft out w/o pulling the cylinder jug? Just wondering if I can skip wrecking 1 gasket while I'm at it. Part of me wants to just check the piston rings anyway, but based on the condition of the bore it's all fine.

Wouldn't recommend it, and don't think you can.

If you're gonna go to the effort to clean etc, just get a top end gasket kit and it will include everything anyway. Lots cheaper than buying individual gaskets.