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Hey guys, I need alil help getting my kids Kdx tuned. Its running horribly rich down low. But seems to go good when on the pipe. Spooge dripping out of silencer to pipe joint.

This is what I've lately. All new bearings, rod, seals on bottom. New top end, honed cylinder, cleaned pv completely. Went thru the Carb, cleaned real good put new jets, set float (which I seem to have trouble with on the pwks for some reason. It never seems right. But it does not leak out over flow either.

Current jetting. 40 PJ, 155 mj, floats at 16mm, 1174 needle at 3rd clip. #5 slide. As1.5 out. B7es plug. I'm at loss on this now.....also timing mark is set at most CCW mark or the furthest to the left. Is this advanced or retarded? Please throw suggestions guys,

What's your altitude and climate like? Those jetting specs are a pretty good start for the average KDX. When you worked on the carb, did you dip it by any chance, or use anything other than spray carb cleaner? It's possible the jet block gasket has a leek.

Any other mods/changes from stock on the engine? i.e.: RB carb/head mods, aftermarket pipe/SA, reeds, etc? These will all impact proper jetting. OEM for the H models is PJ48 MJ160, so it seems you are already starting out towards the lean end of the range. The plug is fine, a BR7ES is just one heat range hotter than the OEM BR8ES, which helps prevent plug fouling when your jetting is too rich. I'm not an expert and am still learning the black art of jetting, but a great place to start is http://kdxrider.net/forums/viewtopic.php?f=105&t=1156.

Also, by running rich down low do you mean it's bogging coming off idle, or sputtering? Bogging is a lean condition, sputtering is rich. PJ and AS are you big hitters from 0 to 1/8 throttle so make sure that is set correctly first. Properly setting AS will help you determine if your PJ is correct or not, then everything else builds off that. Good luck and let us know how it goes.

Julien D wrote:What's your altitude and climate like? Those jetting specs are a pretty good start for the average KDX. When you worked on the carb, did you dip it by any chance, or use anything other than spray carb cleaner? It's possible the jet block gasket has a leek.

No, i didnt dip it. just spray cleaner. Altitude is 0-1000 and temps 40-55f
ive never heard of a jet block gasket. assuming its the same as needle jet (fuel inlet)?

No, no mods other than PC pipe, Fmf TC II silencer.

buff,
what i mean is it is sputtering real bad down low and smoking bad like an old steam lokey steams

I'd start with the jetting guide at step 1 and see where that puts you. Definitely sounds like your running overly rich. What ratio are you mixing BTW? I have found some oils smoke a lot worse than others, and I ended up running 40:1 with good results ...of course after I finish the hybrid I get to do it all over again!

If your putting jets in, the jet block is the part the jets are threaded into. The get block is attached to the carb body with two security torx bolts. Between the get block and main carb body is a rather complicated o-ring type seal. Being rubber, some carb sprays or immersion cleaners degrade that seal. When it leaks, fuel is being sucked directly past that seal in addition to what is already metered through the jets. Hence pig, no matter how small you go on the jets.

K guys, finished with step 1.
3.5 turns out is highest idle.
When I was bike shop earlier I picked up 1 size smaller today along with packing for silencer
after I swap it ill check back in.

Hey guys, beings this is my first go around with the KIPS system. Do they have a very distinct rattle coming from pv area.

That rattle would be known as "the KIPS rattle". Yes they are noise. To the point that many people that are not familiar with the KIPS will tell you that you have an issue on your hands.

rbates9 wrote:That rattle would be known as "the KIPS rattle". Yes they are noise. To the point that many people that are not familiar with the KIPS will tell you that you have an issue on your hands.

haha lol! No kidding! when i first got the bike it did it, i didnt even ride it. pulled it down and rebuild top n bottom ends to be safe. and well its still there. no biggie to me. but my wife was walking by when it was idling...she said: what the hell is wrong with that thing! kinda hurt my feelings.

Okay, i swapped to a smaller pj beings i was 3.5 turns out with AS. it runs alil better down low, now when i have AS more than 3/4 out it bogs when i snap the throttle. Might go back to the 40?

its still lacking some tractor grunt. it rips on the pipe thou. feels alot like a 125 2t right now.
please keep throwing some suggestion guys, its getting closer. how bout stator timing....where is the stock setting?

What size sprockets are you using? Not sure if it will make that much of a difference though. . .

Took it out today, watched n listened as the kid rode. Sounds lean down low gunna go back to the 40 PJ, rips good on pipe but loads up bad when just putting around. Lots of Spooge on swingarm, fair amount at silencer. Also, seeing evidence of either the cylinder not completely sealing at base under reed area and or the cases. Not sure. im starting to lean towards reeds and or jet block gasket as Julien D had mentioned.

hey guys took the H1 out again today along with D2 250. first off i was alittle surprised how the well the 250 runs.
Reason im posting is cause the little H1 has a carby issue that i know NOW is not a jetting issue. It has to be the jet block gasket and or inlet seat. Cause it ran thru almost a tank in not very long. And of course we were way out in the sticks!! Heavy smoke, lots of spooge at pipe joint dripping on swingarm.
If it was the inlet seat wouldnt that make the excess flow out overflow tubes??? Basically like a incorrect float setting??
Also, it does not foul plugs, plug is of course dark. How would you guys attack this issue?
Just order up jet block gasket and new inlet seat? Viton tip looks great and spring loaded part seemingly works good.

Not much you can do with the seat other than visually inspect it for damage, can't replace it. If float height was off (or seat damaged so that it doesn't seal, you'd likely have a big puddle under the bike...easy enough to check just turn the fuel petcock to on and wait. If the jet block gasket were bad you'd probably run really rich, but couldn't see you burning gas fast enough to notice the difference that easily.

Consider that with a faulty and leaking jet block gasket, an abundance of fuel is sucked into the carb throat without being metered by the installed jets. When you think of it that way, it is easy to understand why fuel consumption could be drastically increased, and an excess if spooge and smoke is present in that situation. The jet block oring is pretty cheap, might as well change it and see if that helps before diving into something else.

I'm just gunna order up an oring. What size carby are these? 33 or 35mm.

A 200 stock is a 35mm and a 220 stock is a 33mm. But for a jet block gasket it shouldn't matter.

Ok, thanks. Ill report back after I get the oring installed.

Two zip ties, one on either side of the rubber expansion chamber/silencer connector will stop the drip on the swingarm. Of course it won't stop the spooge but it will at least keep the bike cleaner. I just don't like that greasy stuff so close to my rear brake rotor.

I found two o rings that are a little too small and roll them into the groves on the connecter and that works great to keep the joint sealed. But you have to remove the silencer to get them on.