julien_d said:jetsrus is a great place to get individual jets, which is what you need for jetting. Get various sizes and start testing.
For a "jetting kit", JD's jetting kit is a good option if you want to make the job easier. BTW, you probably won't have much success if you're trying to jet it for spooge. You need to jet it for performance. KDX's will always spooge. You probably need to clean out the silencer 1st...
I warmed up the bike for a few minutes then put a piece of paper right next to the tailpipe for about 4 or 5 minutes with the throttle ranging from idle all the way up to about 2/3 throttle...This picture is what the paper looked like after 5 minutes..(notice the dripping on the wheel also). The spark plug looked a little wet when I took it out)..I'm not sure how to clean out the silencer since it is all sealed and there looks to be no way to change out the packing..Nothing came out of the drain plug after this short runup.julien_d said:No, you are correct. If the jetting is overly rich you could be blowing oil out the back. However, if it is that rich it would probably be fouling plugs as well. Have you checked the condition of the top end? Compression is within spec? Have you cleaned out the silencer? They eventually soak up all the spooge they can and then it starts coming out the back. If it's a stock silencer there should be a drain plug on it.
It is possible to reduce spooging effects with proper jetting, but the bike needs to be in top shape engine wise before even trying to jet it. If it's spooging because the silencer is clogged, or because the top end is in poor condition causing blow by, or the RH crank seal has failed, then you try to fix it by going leaner and leaner on the jets, soon you could have a trashed engine.
Just throwing that out there to give you some info. If the engine is in good repair and the silencer is clean and it's still spooging too much, then there are jetting problems, yes.
julien_d said:Shew nasty! What type of gas do you use, what type of oil, and at what ratio? Do you know what the jetting is now?
The main jet is a 160 and the pilot a 48...This KDX has the airbox lid removed with a brand new Twin Air filter, VForce3 Reeds and an FMF Gnarly pipe with stock silencer. That's all the info I can gather on a Sunday nitesr5bidder said:jeba6208
you don't need a kit any good local shop is going to have the main jets for around $2.50 and the Idle jets for around $6.50.
Take the carb apart and let us know what sizes are in there now, beg borrow or steal a compreesion gage with the proper thread size for your spark plug holeand check the compression, check under the seat and make certian the air filter is clean , is there an air box lid and snorkle?
with that much oil I'd drain the transmission oil and change to ATF type f for a test to see if your right crank seal is leaking (looking for a difference... color on your paper or smell)
julien_d said:Good enough. I'd bet it is indeed running quite rich. That main is HUGE. I hate to give people any recommendations on where to start. If you're not fouling plugs you can't be too far off. Try a 158 or 155 main jet? You may end up needing to go down further. It'd probably be a good idea to have jets on hand from 150 - 158 at a minimum. Perhaps a 45 and 42 pilot jet to try out as well.
Again, the JD jetting kit is always a good way to go. I hear great things about his needles, and how much his kit simplifies the whole process.
J.
Sandman 2.0 said:Stock mine was really rich, for what its worth I run 155/45 dropped needle one notch, air box lid cut and stock pipe and silencer. Bike now runs great but still spooges a bit. I agree with Julien that KDX's just seem impossible to stop the spooge completely. Mine run very crisp now, nice brown plug, idles great and no blubbery throttle response. I'm at 800 above sea level. I think the 155/45 is a great starting point and adjust your air screw to suit.
sr5bidder said:might be a good time to remove the silencer and pipe and flush them out with kerosene or oven cleaner, If it where my bike I'd pop the top for a top end inspection/kips cleaning now as well, many of us have been able to do this and reuse the base and head gaskets. but at least if you clean the pipes out when you rejet you'll know that if its blowing oil out, its new oil
I rebuilt my engine, cleaned the pipe/repacked the silencer and dropped the neddle to clip 2 ...42/155and have about 6hrs on it with no signs of spooge (yet) and just enough smoke to make me feel safe
Unless you want a kdx torch, DO NOT fill your silencer with anything flamable! Yes, there was packing in there at one time. You can jury rig it, or drop around 50 bucks for one that comes apart. Vintage Bobjeba6208 said:I'm assuming from the look of the stock silencer that there is no way to open it up?...Should I just fill it 1/3 of the way up with kerosene and shake it up? (is there any packing in that silencer or just a baffle?)
whenfoxforks-ruled said:Unless you want a kdx torch, DO NOT fill your silencer with anything flamable! Yes, there was packing in there at one time. You can jury rig it, or drop around 50 bucks for one that comes apart. Vintage Bob