Bike won't stay running - help!

Is there anyone in the Denver area that can figure out my bike? I will pay you. I'm so fed up.

Two questions for anyone who has the knowledge:

1) Why won't my bike idle?

2) Do I need new rings? I am losing compression as I am able to kick through without having to use the release.

Ever since I YZ timed my bike a couple of years ago, it really never has idled well at all. It always had to be turned in (slide up) and it still wouldn't idle when stopped.

Well today I pulled the carb and removed the octopus. I changed out the pilot air to 100 and the starter to 65 per Clarkes instructions. Plugged up what you are supposed to and cleaned it all out. I have an EKQ #3, 160 main, 40 pilot and screw out 3/4 to 1 1/4.

It took forever to get the bike started. With the choke on, it warms up fine. It will start reving quite a bit and then I turn the choke off. The bike runs a little and then dies. Like it always has. Everything is on the carb correclty according to the book and microfiche pictures.

Then today, as I was kicking my ass off, it started to kick through with no resistance. I was able to use my hand to push it down. I did notice the bolt on the kick starter was loose and I tightened that down. That seemed to help a little but I'm wondering if I need new rings or is my kick starter stripping.

As I said, if anyone in CO wants to do a good deed, I would gladly pay you. I at my wits end.

I remember the good old days when all I would do to bikes is change the oil. Never had any problems with them. Only when I started learing to work on them am I having these problems. :)


Is your decompression lever stuck, or somehow your exhaust valve not closing?

With your altitude, those jet specs may not work. Hopefully Taffy or some other carb guru can lend some help...

It doesn't appear to be stuck. I actually dropped down while I had the carb off. I was running 42 pilot and 162 main. It was running OK with those (it still wouldn't idle with out the choke on) but I thought I would try to go leaner. Do I still have to go leaner than that?

The thing that gets to me is why it won't idle, at any jetting. Ever since I YZ timed it over two years ago. It runs and would always kick over when it stalled. It never quit on a ride unless I stopped. I even tried moving the TPS all through it's range and nothing helped.

My kingdom for a fuel injected dirtbike. What the hell are they waiting for? :)

I think your a little off on the ratio of PJ/PAJ... I would try to get the Sudco PAS screw for adjusting that ratio. I've been running LarryCo setting over here and they work great from 6800ft to 9000 so far.. What is the altitude in Parker? I would try dropping the PJ to a 38 and a PAJ to 60/65 with that EKQ needle.. Also your main is WAY to big for that E series needle.. Bring that down to a 150 - 155 and a MAJ of 160 - 165..

As for the loss of compression, I've heard from other people, that the piston rings could move out of stock alignment position, and could come close to aligning with another rings end gap, which would can cause a loss of compression.

Good Luck,



I agree with're wickedly too lean now on your pilot circuit with that 100PAJ...try 38PJ/65PAJ...or 40PJ/70PAJ...or 42PJ/75PAJ. I recommend the 38 option though...

Cant speak to that decompression issue...keep me posted on how things are going...

FYI...move to MN went OK...except for the fact that my truck's "check engine light" came on right before the twin cities. I think my Tahoe is just about "kaput" (sp?)...


Dougie, you might try lowering the needle to clip #2 also, along with the 38pj and 65paj. If you still can't get it running, Drop me a PM and I might be able to help you out, I live just a few miles away from downtown Parker.

Larry, glad the move went ok. I tried putting the ACV back to stock with the EKP needle #3 and my bike still didn't want to run with the EKP :). I disabled the ACV again, put the EKQ #2 back in and then did the JamesNOW mod to take care of the slight bog when I snap the throttle open. Works great and the JamesNOW mod seemed to give me a little bit more low end response. :D

Dougie. I doubt you need new rings. Try this, it has happened to me on previous my 98' WR400. The manual decompression lever, cable or head lever may be out of spec. Two things lead me to this, 1.) you can push through on the kick start, 2.) the bike will not idle. Disconnect the manual lever from the bars and adjust according to the manual. Check your adjustment on the head lever. I'll bet that's the problem.

I had the stock PAJ of 75 in there and changed it to 100 becuase I deoctopussed. That is per the instructions of Clark way back when. I also changed the start jet to 65 from 60. Those are the YZ numbers as I am YZ timed. However, they are for sea level or close.

But as I look at Curt's Sig., you are YZ timed and deoctopussed too. Looks like you left the start jet alone at 60? Where is the MAJ? What is stock MAJ? So if I can summarize what I should try - EKQ #2, 38 pilot, 65 PAJ, 155 main, 160 MAJ, 60 SJ and a whole lot of hope.

HP, I'll readjust my decomp lever and see it that helps.

Thanks guys. I'll keep you posted.

Dougie, first thing I would do is check the valve clearances. When they start to get tight the bike will start hard. Also if you can kick it without the comp. release is an indication of an exhaust valve not closing all the way.

OK, here is what I went back to for now: EKQ #2 (from #3), back to 42 pilot and 75 PAJ (which was the stock PAJ), 160 main and 200 MAJ (which was the stock MAJ), and back to stock 60 start jet. 1 1/4 out on screw.

EKQ #2

42 pilot

160 main

75 PAJ

200 MAJ

60 SJ

1 1/4 out on screw

I want to get opinions before I put it back on. I won't be able to get a 160 MAJ or 60 PAJ until probably next month, so this will have to do. If anyone has suggestions on what would work with the 75 PAJ and 200 MAJ, I'm all ears.

I can't find the decompression adjustment instructions anywhere in the manual. Anyone direct me to the page number? But if I remember, I want about a 3-5mm play in the lever, which it has. Are there other instructions on the actual adjustment at the engine?

As far as idling goes, I checked the throttle slide against the manual for the 1000th time. It all appears to be correct. The plate is not upside down (hole is at the bottom). I've moved the TPS all over the place trying to get it to idle.

Is the slide plate, which is facing the engine, supposed to open up at all through the idle screw adjustment. I noticed the back of the slide, towards the airbox, does open as the screw is turned in. But the plate side never clears the bottom of the carb. Not sure if that is how it works or not.

One other question on the lack of compression. Am I going to ruin it if I run it that way? I am not going to have time to get it fixed before my trip to Moab over Memorial Day.

The stock starter jet for a '98 WR is a 82, which was WAY too large. When I was doing all the modifications, I moved to a smaller jet on the SJ. The MAJ is right next to the PAJ in the intake bell. If you replace the PAJ, you were probably looking at the MAJ as well. Yes, the PAJ that Clark suggested back then, was before Taffy did his excellent Jetting PH.D in the Jetting Q's thread. If you haven't read that yet, it's long, but well worth the time for a great understanding.

Also, depending on the altitude that you are running, I would try the 150 mj/160 maj. The EKQ is one size larger on the portion of the needle that affects the 0 - 1/4 throttle location so the 150/160 combination that I and others in this area are running will work the same no matter if its EKP,Q or R...


Dougie, sounds like a start. If you get your bike to start with the new jetting, let it idle a little and then check to see if your compression has returned back to normal. If not, I would definately pull the valve cover and check your valves. Also, check the compression release arm on the valve cover to make sure it isn't sticking. If a valve is sticking open, that could spell disaster.

I just check the valves. The Exhausts are right at the speck limit of .30, I can get the.30 in but nothing else. The intakes are between spec at .15 and .20, I can get a .15 in but not the .20. After checking the valves, I am unable to push through the strok with my hand, which I was able to do before. So at least that is a start.

I'm going to go to Thunder Valley on C470 tomorrow. I'll try to mess around with it there. We are going to Rampart on Saturday around 1pm if anyone wants to hook up. That is if it is running.

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