where to go from here. jetting q.

[stainlesscycle]

let me know how it works out. 42 pilot is just on the edge of lean for me. i may try 45/175 again. 178 is definitely rich. it has been my experience that these motors need slightly rich to perform properly.. everytime i get a perfect plug reading it doesn't run great. i go 1 richer and it works well..

 

[stainlesscycle]

on site:

http://www.gasgasons.com/index.php?site=static&staticID=56


can anyone tell me if this is recommended settings or original factory settings?

when i translate it, it says

"Settings advocated the carburetor GasGas ec."

 

[stainlesscycle]

m still tinkering with my 36mm, but i'm at 42/178/ddk on 2/#5 slide/1.5 turns. i'm probably gonna go to 175 on main..

tinkered with it today a bit.

42 pilot (45 pilot idles better, but 42 pilot runs better. i'm debating on what to do here..)
1.5 turns
175 main
#5 slide
ddk needle
#1 clip (i'm never at #1 clip... should i go to 172 main and #3 or #4 clip?) or do i need a thinner needle??????

 

[iancp5]

I'm going to my club's practice land on Sunday if the weather's dry so hope to try a few different settings. I can never tell if jetting is right or wrong unless I ride on proper enduro terrain.

 

[stainlesscycle]

i have the same problem. i test in the yard - but i can't really put a big load on the motor this way... yes my yard is tore up... i've been contemplating making a small bermed oval track with 1 S curve in my backyard..maybe like a mini tt track

 

[Jim Cook]

tinkered with it today a bit.

42 pilot (45 pilot idles better, but 42 pilot runs better. i'm debating on what to do here..)
1.5 turns
175 main
#5 slide
ddk needle
#1 clip (i'm never at #1 clip... should i go to 172 main and #3 or #4 clip?) or do i need a thinner needle??????

When I was a dealer, I spent a lot of time on the phone trying to help customers properly jet their bikes, and I still get quite a few requests for tuning help from other GasGas riders.
It's much easier to do when I can ride, tweak, and ride again to test. Over the phone (and on the forum) it is much harder to do anything except make suggestions and wait for feedback.

I've been following this thread with great interest, and am always trying to learn more; so please indulge me a bit.

This is for/on your '00 200, correct? (One of my "back-up bikes is a 2000 XC200 and one of my sons and one of my best friends race two of the first ten 200cc Gassers that were imported to the US. My son races the bike that Dick Burleson rode in the first Dirt Rider test article on the 200.)

What results are you trying to achieve by the smaller 36mm carb?

Did you have any problems getting the 36mm carb to fit the air boot and intake manifold? (What adapters, if any were used to make it work?)

Thanks in advance.

Good Riding!

Jim

****************************

 

[stainlesscycle]

the reason i switched to 36 carb was to get a more consistent idle, and felt the 38mm carb was just plain old too big for the 200... i assumed a smaller carb could get increased fuel velocity, and gain performance......... ltr was the first to suggest the smaller carb.

no adapters of any kind. fits right in there.

how are your 200's jetted? i could never get the bike to not stall when hot with 38mm carb, unless i jacked the idle way up, and pretty much out of the idle circuit. changing pilots around got me to idle, but lost performance. it would idle fine till it got hot then slowly die. i'd have the idle screw all the way in, and start turning the throttle adjuster so much that the slide wouldn't slap shut...i'd start a race fine, then 10 minutes into it half to jack the idle way up.

 

[iancp5]

My bike came (used) with a 36mm. It already had some plastic adaptors that are clearly home built. Looks like someone managed to find the correct size plastic pipes to cut pieces off. The smaller one is white, the other black - water pipe and drain pipe??

Initially the bike was very down on power. Ok for previous owner who must be half my weight. I put the 38mm back on but still bad. Traced it to a cat pipe with a loose catalyst! Sometimes the bike worked other times it didn't.

I want to try the 36mm because I'm looking for a bit more bottom to mid acceleration/torque/lugging. I already have a Gnarly pipe, PV box, flywheel weight. Tickover hasn't been a big issue on the 200 however it is better with the 36 but this could be a number of reasons not necessarily the size of carb. I am spurred on by the fact KTM went back to 36mm. I'm trying to get a 300 without the aggression so it's trialsy at low revs but can still fly at higher revs. I am looking for a very linear throttle, as standard you get sudden ramp then it becomes linear but still a little lacking in torque at bottom to mid. So willing to sacrifice the ultimate top end for smoother bottom.

 

[stainlesscycle]

My bike came (used) with a 36mm. It already had some plastic adaptors that are clearly home built. Looks like someone managed to find the correct size plastic pipes to cut pieces off. The smaller one is white, the other black - water pipe and drain pipe??

adapters? mine fit right in.. took the 38 out and put the 36 in... according to keihin the 36 and 38 are identical in size..

 

[iancp5]

adapters? mine fit right in.. took the 38 out and put the 36 in... according to keihin the 36 and 38 are identical in size..

Mine's smaller engine side and airbox side. Must be different models of carb although it looks identical so it must be a PWK. The size of spacers required is consistent with the carb being 2mm smaller. I have never actually measured just believed the previous owner! Maybe I have an even smaller one. The slide in my 36mm is shorter than the 38mm slides as well. Otherwise they look identical in all respects. Looking at the carb on the bike it looks identical to the 38.

 

[RBD]

The slide in my 36mm is shorter than the 38mm slides as well. Otherwise they look identical in all respects. Looking at the carb on the bike it looks identical to the 38.

I bet you have a PWK 35 mm carb on it, they look the same, but thay are a little smaller in body size.

Ron

 

[Jim Cook]

the reason i switched to 36 carb was to get a more consistent idle, and felt the 38mm carb was just plain old too big for the 200... i assumed a smaller carb could get increased fuel velocity, and gain performance......... ltr was the first to suggest the smaller carb.

no adapters of any kind. fits right in there.

how are your 200's jetted? i could never get the bike to not stall when hot with 38mm carb, unless i jacked the idle way up, and pretty much out of the idle circuit. changing pilots around got me to idle, but lost performance. it would idle fine till it got hot then slowly die. i'd have the idle screw all the way in, and start turning the throttle adjuster so much that the slide wouldn't slap shut...i'd start a race fine, then 10 minutes into it half to jack the idle way up.

Our 200s have the #7 slide in the 38mm carb. They all have the 42 pilot jet. With the smaller pilot jets, they tended to bog on hard acceleration, and the 40 pilot jet was the smallest that we could get them to idle with. We use a variety of jet needles, from the N1EF to N1EH and the original LTR needle, and from a 178 to a 180 main, depending on ambient temperature and intended usage.

On my 2006 DE300, I can get more power (stronger pick-up from idle) on acceleration from a 45 pilot, but with all the mountain single track that I ride (in the sub 3000' Ouachita and Ozark mountains of Arkansas) throttle responce is more "crisp" if I use a 42 pilot jet. I run the N1EG needle with the clip in the 2nd groove from the top (#2 position).
If I'm running a hare scramble in colder weather, I may use a 180 main jet. Otherwise, in hot weather I use a 175 main, (We recently had eleven days in a row with temps over 100F and 60+% humidity.) snd in colder weather (when it gets below 55F) I will run a 178 main jet for normal trail riding and working.

Good Riding and Tuning!

Jim

 

[iancp5]

I bet you have a PWK 35 mm carb on it, they look the same, but thay are a little smaller in body size.

Ron

Could be.
What should I be doing on jetting as a baseline. Down a bit all round due to the stronger signal a 35 would provide? I'm thinking it might not matter on the pilot but maybe down a notch on the needle and a size or two on the main? 175 or smaller? Maybe just the main needs to shrink?

 

[stainlesscycle]

I bet you have a PWK 35 mm carb on it, they look the same, but thay are a little smaller in body size.

Ron

yep. 36mm carb is marked s63...

 

[iancp5]

Whatever my carb is, lets assume it's the 35mm as it has the shorter slide, it worked well today.

I went to my club's practice day to find it was actually a closed to club Hare & Hounds (Hare Scramble). I wasn't prepared to race so just let everyone start and used it as a test for an hour. I was running 40P, 175M and DEK needle on #2 with a #5 slide. The bike performed very well and ran better than it ever did on the 38mm. It wasn't quite perfect there was a slight bog/hesitation at 1/4 - 1/2 throttle low to medium revs climbing. I think it's too rich here - how do I tell the difference between a rich bog and a lean one? I think rich because it 4 strokes quite a lot at small openings on the flat at low revs. At high revs it pulls cleanly at any throttle opening. I couldn't tell if it had a little less power WFO on the smaller carb, it doesn't feel like it's lost anything at top end.

I couldn't make any adjustments in the field because they started the course on a wet, sandy MX track so I didn't dare pull the carb open for fear of getting muck in.

I have a race next weekend and if it is rich 1/4 - 1/2 I think I may try the DEK on #1 or an EGK on #3 (If I get one in time).

 

[iancp5]

Update - it was a lean bog. Raised the needle and response improved. Still not perfect but as I could only test on the road I'm going to have to race it next weekend and see how it goes. Still hesitates a little but as only at low revs/high gear I'm not sure if it simply needs to come on the pipe.

Currently at 40P, 175M, DEK on #3, Slide #5 on the 35mm carb.

 

[iancp5]

(35mm Carb on 200)

I had a fiddle with the jetting again and raced on the following setting:

38P, 175M, FEJ on #2, slide #5

Very good everywhere except right at the bottom where it's too rich, wont idle and needs quite a bit of throttle to start pulling. Once past 1/4 throttle it seemed to respond well. Will try a 35P. An FEK needle would be a better solution I feel except they don't exist according to JD chart.

 

[stainlesscycle]

it's possible it won't idle due to lean condition on pilot???

also, i found my float to be too high ,even though i checked it twice.. i lowered it a tad..
i'm gonna jet some more - i should have it completely solid later today.

 

[iancp5]

it's possible it won't idle due to lean condition on pilot???

I think so. Remember I have quite a different needle, slide & carb to most 200 Gassers. Normally when running the single taper needles people get good resullts with those ending with K which is a larger base diameter. When I tried DDK & DEK needles it idled nicely with a 42P. Now with the FEJ it's too rich I think - spluttery and 4 strokey on tiny throttle openings. On the FEJ needle I have tried 42P (tons of smoke and no idle) 40P (idles for a few secs) to 38P (will idle very slowly with idle screw full in). Anyway I'll try a 35 and see what happens. I think were there such a thing as an FEK needle I wouldn't need a small pilot. I know at idle the needle is not supposed to do anything but that isn't the impression I get from the changes. As soon as I went to FEJ it wouldn't idle.

 

[Jim Cook]

I think so. Remember I have quite a different needle, slide & carb to most 200 Gassers. Normally when running the single taper needles people get good resullts with those ending with K which is a larger base diameter. When I tried DDK & DEK needles it idled nicely with a 42P. Now with the FEJ it's too rich I think - spluttery and 4 strokey on tiny throttle openings. On the FEJ needle I have tried 42P (tons of smoke and no idle) 40P (idles for a few secs) to 38P (will idle very slowly with idle screw full in). Anyway I'll try a 35 and see what happens. I think were there such a thing as an FEK needle I wouldn't need a small pilot. I know at idle the needle is not supposed to do anything but that isn't the impression I get from the changes. As soon as I went to FEJ it wouldn't idle.

If your "idle screw" is the "throttle stop screw", then you are no longer using just the pilot/idle circuit. Instead, you are raising the slide and needle to the point that you are now getting into the "needle jet/jet needle" circuit by raising the slide with the throttle stop screw; effectively bypassing the idle circuits.

Jim