my first Gas Gas

paulos

New member
g'day all, I've just joined the brethren by picking up my very first Gasser, a 2005 model EC200. The previous owner seems to have been a bit lax on the maintenance/tuning side of things so I've been going through the bike and sorting out the little bits and pieces to my liking.

I haven't had much of a ride yet as the throttle cable that was on the bike was about 10mm too long and the adjustment available wasn't enough to take up the slack, I've just fitted a new cable (among other things) so hopefully will get on it in a day or two.

Just a quick question re jetting? The short ride I did have suggested the bottom end was a bit doughy, it has what I'm assuming is a red JD needle in it, clip two notches from the top. The slide is a #5. From what I've read on here these two elements are the main culprits in lack of low-end power, would you change one before the other? I like to change things one at a time (unless it's all blatantly wrong :D )

Also, to push the friendship, are the oversize powervalve covers worth a look on the 200?

Cheers
Paul
 
Congrats on your purchase and welcome. You will soon realize one of the most valuable apects of owning a GG is this forum.
 
doughy bottom end

There is always more than one way to approach the jetting. Some people here on the forum have attacked rich bottom ends with slides that have more cut-away (higher # on slide), I prefer to stick with 5~6 cut-away slides and focus on the JN. Usually the straight diameter will cover idle and off idle areas. So I recommend you find the next two leaner JNs based on starting straight diameter. The clip position does little to nothing in this region. Also, in relationship, the JNs are pretty inexpensive compared to the price of slides. In my EC 250 I use a 6.0 slide w/ a notch in the center. I have been able to get it to run clean and crisp on the bottom end by changing the JN. The sooner you can get the main circuit active, the less chance to get a light switch response when transitioning from the slow circuit to main circuit. Much like the Lectron principle of using the JN/Main circuit to do most of the work.
 
I love this bike already

thanks for the welcome and the info guys.

I went for a half decent ride this arvo, only 20 minutes or so up the mountain range behind where I live. I can see why everyone raves about the handling on these things!! This is the most confidence inspiring bike I've ridden. I had an older KTM300 previously and felt like a passenger by comparison, this Gasser is so nimble it's like it has telepathy! I'm in love :D

Back to the jetting though, I have ordered another needle, a CCL, which someone in the jetting thread was using in an 04 EC200, so I'll see how that goes. I did drop the JD needle in the bike to the last (top) notch and it certainly seemed better than my previous short ride, although it still stumbles a bit low down.

For what it's worth the current jetting is 38 pilot, #5 slide, 165 main, and JD red needle. Where I live/ride the elevation is from 36 - 375 metres (100 to 1200 ft)

Thanks again for the input, much appreciated
 
ok then

So the CCL needle arrived in the mail, and was visibly smaller than the red JD needle. I put it in for a test anyway but the results were as expected. The spot I'm using for jetting runs is mostly uphill with a few fast straights and switch-backs. The new needle bogged on all the corners and was a struggle to keep the bike running when coming back down the hill.

I put the JD needle back in for a fresh comparison and it was definitely much better. The problem is that it's on the top notch and I reckon it could be cleaned up a bit more down low. So, do I try and figure out what genuine needle is close to the JD needle so I have something to work from, drop the pilot (try my balloon :D ), buy one of these oversize powervalve covers?

The shop I got the needle from had no idea/interest in the JD needle specs, just wanted to get me using a standard needle as a starting point. Fair enough, but I thought some measurements from the JD needle might have been useful?
 
Jet Needle

It's tough working with a JN that you do not have the specs on. Do you have a micrometer that you can measure the straight diameter of the JN before the taper starts? That will tell you something from idle to 1/8. Is it visible to see where the taper starts in relation to the clip groove for each JN? To get a good idea of when the taper starts working in the needle jet.
I would recommend trying the CCL in different clips before giving up. Did it seem rich or lean?
 
Thanks mate, the CCL definitely seemed rich. I expected it to after comparing it to the JD needle.

I do have digital verniers , are you saying the section before the taper controls the idle to 1/8 throttle? I can measure the JD needle and compare it to the needle chart posted on here. I should mention that I've had to adjust the throttle cable a bit to get the bike to idle.
 
yes, measure before the taper starts. Normally it is on the straight diameter before the slide opens and a period of lift. it varies by JN. That why I suggest measuring the length from top clip groove to start of taper. You can tell which JN is starting on taper sooner.
 
I would email or call them direct they could save you a lot of time and headaches they are jetting PROS.

http://www.jdjetting.com/

The guy I spoke to here in Aus seemed pretty clued up, he's actually got a gas gas himself, but I'll keep your advice in mind.

I've read a few on the jetting sticky's posted on here and I've gone back to square one. The bike won't idle unless I wind the throttle cable out a fair amount or lean out the airscrew 3+ turns. I'm going to try a couple of smaller pilots before I do any more to the needle. The bike rips once you get past 1/4 throttle so I'm thinking the needle in it might be ok.

Thanks to all for your advice, much appreciated.
 
First proper ride

Went out on the weekend with a few mates to a natural terrain track we use for Vintage MX, and had a good run on the Gasser. I think I've got the jetting pretty well spot on, although the hesitation at low revs is still there. Having read through a few threads in other sections I reckon the powervalve might need adjusting as there is definitely a "clatter" just off idle.

I'll read and re-read all I can on powervalve adjustment, and stay away from the beer fridge while I'm doing it :D
 
well I had a look at the power valve after reading the thread re adjustment and issues. Sure enough there was a heap of play and the arm was also hitting the case, so I adjusted it up and ground a couple of mm off the corner of the arm. All is good now! The bike will idle off the idle screw with the air screw 2.5 turns out and the throttle cable adjusted back to just taking up the slack. Better still the bike will pull away cleanly from less than walking speed.

One last (hopefully) jetting question though. I put a 35 pilot jet in as part of my previous jetting experiments, how would I tell if this is actually too lean?
 
well I had a look at the power valve after reading the thread re adjustment and issues. Sure enough there was a heap of play and the arm was also hitting the case, so I adjusted it up and ground a couple of mm off the corner of the arm. All is good now! The bike will idle off the idle screw with the air screw 2.5 turns out and the throttle cable adjusted back to just taking up the slack. Better still the bike will pull away cleanly from less than walking speed.

One last (hopefully) jetting question though. I put a 35 pilot jet in as part of my previous jetting experiments, how would I tell if this is actually too lean?

Well done you on sorting the powervalve ! Did you get rid of your low-rev hesitation too ?

Seems we are always searching for a better (In whatever way that may be per-se) connection between throttle-hand and rear tyre. Go on TT for example and in any one section; a good portion of the topics are about "fuelling"..........

I messed around with carburetion on my XR400 to 'perfect it', had a few (They all do that Sir !) leak jet, and accelerator pump diaphragm etc problems with a WR250F and then had the "normal" Throttle Position Sensor problems [Re: Flame-outs] on a KTM 500 EXC.

BUT: Funnily enough....cross my fingers ;).....touch-wood :)......my Gasser is the first off-road bike ive had where its run truly stonking from tick-over to 'redline'. Its never so much as spluttered, hesitated, coughed or held back anytime or anywhere. Ticks over a treat too.

Im presuming one of the previous owners has re-jetted, and must investigate the carb one day just to see what settings its running. But for the moment im too busy riding :D
 
Well done you on sorting the powervalve ! Did you get rid of your low-rev hesitation too ?

Yeah mate, all good! The power now is very linear, there's no hesitation at all . I was pretty happy with the bike beforehand, I'm absolutely stoked now!:D

I might put the 38 pilot back in and see how it runs. I'd rather be on the safe side of lean.
 
If its lean on the pilot you'll notice a few things.

Typically the idle will hang on decel and won't return smoothly to idle. It will surge a bit. The power right off idle will be weak and you'll need to clutch more than you previously did. And also, if you wick the throttle open quickly from idle the bike will hesitate and then rev (kind of gasp for air). If its really lean it will actually refuse to take revs until you back the throttle off again. Super lean it will stall.
 
If its lean on the pilot you'll notice a few things.

Typically the idle will hang on decel and won't return smoothly to idle. It will surge a bit. The power right off idle will be weak and you'll need to clutch more than you previously did. And also, if you wick the throttle open quickly from idle the bike will hesitate and then rev (kind of gasp for air). If its really lean it will actually refuse to take revs until you back the throttle off again. Super lean it will stall.

Cool, thanks for that, I'll have a bit more of a ride tomorrow and see if I can pick any of those symptoms. Cheers
 
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