I have a few jetting questions about my bike. I am currently running the factory jets etc.. in the carb(180 main,45 pilot,NOZG needle #3 position,1.5 as, #6 slide).I am running 40:1 CompII Silkolene oil.The jetting has never been right since I bought the bike.I ride single track tight trails in Indiana. The thing was running rich during the summer but never rich enough to foul a plug.Did have a lot of oil spooge coming from the muffler though.I went out and rode about 25 miles this weekend (temp. around 50 F) and it seemed to run good once on the throttle but it had a nock when decelerating and would not idle steady(the bike would rev slightly when stopping at idle.) I know it will not be the same both summer and winter and I ride a lot all year round. I currently have a 178 and 182 main,48 pilot, and NOZH needle but not sure which if any to use.I would like to do what I can with the parts I have until I can order different jets as needed. Thanks
00 KTM 250 EXC Jetting????
- Thread starter kadman
- Start date
B
biglou
It's early so this will hurt my brain, but let me see if I have this right:
Surging is a sign of being lean (I think). I've had mine act this way after being heated up during some serious hi-RPM/low-speed woods riding.
I also think that you might go one leaner on the pilot or perhaps raise the clip (lower the needle) one mor notch to take care of the off-idle response.
The knocking you here could be the power valve closing. I can hear mine when I am on-and-off the throttle very quickly or when I "chop" the throttle sometimes.
Surging is a sign of being lean (I think). I've had mine act this way after being heated up during some serious hi-RPM/low-speed woods riding.
I also think that you might go one leaner on the pilot or perhaps raise the clip (lower the needle) one mor notch to take care of the off-idle response.
The knocking you here could be the power valve closing. I can hear mine when I am on-and-off the throttle very quickly or when I "chop" the throttle sometimes.
jeb
Member
- Jul 21, 1999
- 633
- 0
Here are the jetting specs I used in my 99 250 E/XC. Since you already have the needle, it might be worth a shot.
45 pilot @ 1.5 turns out on the air screw
170-172 main jet
NOZH needle in the 2nd leanest clip (2nd from the top)
Stock slide
This is running at about 1000' most of the time. Summer temps. Pump 92
premium at 40:1 with yamalube 2R. It ran well for me with no spooge on both the stock exhaust setup and a full FMF setup (M21 or M29 pipes w/TCII).
You may still get some spooge depending on your premix. One of my riding
buddies has the exact same bike and doesn't like Y2R so he tried a bunch
of other 2 stroke oils. They all spooged with this jetting anywhere from
not bad to really bad. He finally went to Y2R and it cleaned it up. His
bike still ran well with this jetting and was not fouling plugs just more spooge.
With the cooler temps in the fall in the upper midwest I'd go to the middle clip on the needle to richen it up just a bit.
45 pilot @ 1.5 turns out on the air screw
170-172 main jet
NOZH needle in the 2nd leanest clip (2nd from the top)
Stock slide
This is running at about 1000' most of the time. Summer temps. Pump 92
premium at 40:1 with yamalube 2R. It ran well for me with no spooge on both the stock exhaust setup and a full FMF setup (M21 or M29 pipes w/TCII).
You may still get some spooge depending on your premix. One of my riding
buddies has the exact same bike and doesn't like Y2R so he tried a bunch
of other 2 stroke oils. They all spooged with this jetting anywhere from
not bad to really bad. He finally went to Y2R and it cleaned it up. His
bike still ran well with this jetting and was not fouling plugs just more spooge.
With the cooler temps in the fall in the upper midwest I'd go to the middle clip on the needle to richen it up just a bit.
woods_rider1
Member
- Sep 27, 2001
- 355
- 0
Kadman
if I may lend my $.02, have you tried a single taper needle? It really helped my bike ('01 250 MXC) I tried the NOZG and NOZH, and going to the DDK or CEK needle was a night and day difference in the power delivery! VERY smooth in the slick muddy woods! w/less of a hit going into the mid range. If this is what you are looking for, give them a try, they are $5.00 each through SUDCO.
if I may lend my $.02, have you tried a single taper needle? It really helped my bike ('01 250 MXC) I tried the NOZG and NOZH, and going to the DDK or CEK needle was a night and day difference in the power delivery! VERY smooth in the slick muddy woods! w/less of a hit going into the mid range. If this is what you are looking for, give them a try, they are $5.00 each through SUDCO.
kadman - why not jet what KTM says you should. You have an orange book that came with your bike. In the back are jetting charts.
Put those jets in, try it out....
I've had '98, '00, and now an '02. Me and the buddies follow the chart with good luck. We get some spooge/drool when riding really technical stuff, but no plug fouls. My '02 came with a leaner slide (6.5), and runs a little cleaner off the bottom
We are three A enduro riders, all riding at elevations from 1,000' to 9,000' regularly.
Put those jets in, try it out....
I've had '98, '00, and now an '02. Me and the buddies follow the chart with good luck. We get some spooge/drool when riding really technical stuff, but no plug fouls. My '02 came with a leaner slide (6.5), and runs a little cleaner off the bottom
We are three A enduro riders, all riding at elevations from 1,000' to 9,000' regularly.
- Thread starter
- #6
Thanks for all of the reply's so far. I have all the books that came with the bike. I checked the book and I am spot on with what they say for the temps. I'm riding in. Most of my concern right now is the unstable idle and knock at idle. I think it is running lean!!! Thanks again.
Last edited:
- Thread starter
- #7
Well I tore the carb down and used about 3/4 of a can of carb cleaner on it and it still had the same problems. I replaced the 45 pilot with a 42 and still had the same problem. At low speed when decelerating or coming to a stop it actually sounds like valve clatter you would here in a car.The engine still revs up when coming to a stop and then returns to idle. I can also feel the bike "lurching forward" when going through the woods in first gear. Any ideas?????
Kadman
Purchased a leftover 00 250 EXC last year and had similar problems except for the high idle when slowing down. Here`s what I found has worked the best for me so far. 182 main/42 pilot/NOZH needle and arond 1 1/2 on the air screw. When my bike was new it sounded like it was being hit with a ball-peen hammer on the cases when I backed of the throttle. My dealer told me to exp. with different mixtures of race/pump gas. I now run 1/3 race gas(110 oct) and 2/3 prem. with Golden Spectro at 50:1 and only get "the knock" when first started cold for maybe the fist min. then it disapears. The main was a little rich during the summer but is working fine now.
I do my riding in SW Oh ,Ky , and Ind.
Frank
Purchased a leftover 00 250 EXC last year and had similar problems except for the high idle when slowing down. Here`s what I found has worked the best for me so far. 182 main/42 pilot/NOZH needle and arond 1 1/2 on the air screw. When my bike was new it sounded like it was being hit with a ball-peen hammer on the cases when I backed of the throttle. My dealer told me to exp. with different mixtures of race/pump gas. I now run 1/3 race gas(110 oct) and 2/3 prem. with Golden Spectro at 50:1 and only get "the knock" when first started cold for maybe the fist min. then it disapears. The main was a little rich during the summer but is working fine now.
I do my riding in SW Oh ,Ky , and Ind.
Frank
- Thread starter
- #10
Hey, 242frank
Thanks for the info. What position are you running the clip on the needle? I have been out working on mine tonight. I'm getting closer.It got dark on me and my headlight stopped working....in the middle of the woods.....pinned in third gear!!!! I found out I don't know those trail that well after all !!!! I may try this set-up tomorrow night. Thanks
Thanks for the info. What position are you running the clip on the needle? I have been out working on mine tonight. I'm getting closer.It got dark on me and my headlight stopped working....in the middle of the woods.....pinned in third gear!!!! I found out I don't know those trail that well after all !!!! I may try this set-up tomorrow night. Thanks
Kadman -
I started out in the middle pos. then ended up going up one leaner. Also one thing I forgot to add was that trying a few different plugs seemed to make a bit of a difference also. I ended up with an NGK BR8EVX (Platinum = big $).
One other thing - I talked to Enduro Enig. on the phone and was told that there was a design change on the head midway through the prod. year and if the part # cast into the head(I think you have to remove the tank to see it) doesn`t have an * after it , it is of the design that they scraped mid way through. I was told these bikes are pretty hard to get spot on in the midrange jetting.
My bike is still not where I think it could be but it definently is rideable for now.
Know where I could get some seat foam like an XR-600 for my bike + a seat cover ? I have an E.E. soft seat foam but it just doesn`t have enough foam going back towards the rear fender. This things KILLING me!!!
Frank
I started out in the middle pos. then ended up going up one leaner. Also one thing I forgot to add was that trying a few different plugs seemed to make a bit of a difference also. I ended up with an NGK BR8EVX (Platinum = big $).
One other thing - I talked to Enduro Enig. on the phone and was told that there was a design change on the head midway through the prod. year and if the part # cast into the head(I think you have to remove the tank to see it) doesn`t have an * after it , it is of the design that they scraped mid way through. I was told these bikes are pretty hard to get spot on in the midrange jetting.
My bike is still not where I think it could be but it definently is rideable for now.
Know where I could get some seat foam like an XR-600 for my bike + a seat cover ? I have an E.E. soft seat foam but it just doesn`t have enough foam going back towards the rear fender. This things KILLING me!!!
Frank
James Dean
Member
- May 17, 2000
- 137
- 0
Same Bike in My Garage
-
Kadman,
I also have a '00250EXC and found the knocking on deceleration to be excessive. Any clean running jetting produced it, and I have LOTS of carb parts in my tool box. The only acceptable result was a mixture of 40-50%race gas and pump gas. Test ridden back to back by adding the race fuel to the tank stopped the knocking immediately. I tried 30% race, but it came back to a small extent.
Also check the ignition timing. Mine was on the edge of the 2 marks towards more advance. I shifted it slightly to the lesser advance mark.
With the stock needle most guys use clip #2 and live with a little sputter. Try your richest needle in the leaner clip position first. (NOZE or F #2)
Needles DDK#3 and CEK#4 are great choices for clean jetting, #45 pilot, #175 main. Small amount of spooge after 50 miles and smooth delivery. NOZ- will give more hit coming off the sputter though, looped mine out the first week I had it.:confused:
James
-
Kadman,
I also have a '00250EXC and found the knocking on deceleration to be excessive. Any clean running jetting produced it, and I have LOTS of carb parts in my tool box. The only acceptable result was a mixture of 40-50%race gas and pump gas. Test ridden back to back by adding the race fuel to the tank stopped the knocking immediately. I tried 30% race, but it came back to a small extent.
Also check the ignition timing. Mine was on the edge of the 2 marks towards more advance. I shifted it slightly to the lesser advance mark.
With the stock needle most guys use clip #2 and live with a little sputter. Try your richest needle in the leaner clip position first. (NOZE or F #2)
Needles DDK#3 and CEK#4 are great choices for clean jetting, #45 pilot, #175 main. Small amount of spooge after 50 miles and smooth delivery. NOZ- will give more hit coming off the sputter though, looped mine out the first week I had it.:confused:
James
James D, I had the same trouble with my '99 300, and I solved it exactly the same way. Fifty percent race gas works great; anything less brings back the slight knock. I use an N85D-2 needle, and I do live with a tiny sputter, but it really comes on hard everywhere. My son won't ride it now that it's jetted clean; he used to like the soft delivery when it was running rich, but now it's just too much for his 130 pounds to handle.
- Thread starter
- #14
James D.
Thanks for the info. I have been reading some of your stuff on the Holeshot forum. I have not messed with the main jet yet but it is next on the list. I took your idea on the needle clip and raised it one notch tonight. Got dark before I had a chance to try it.I plan on purchasing a few other needles to try out also. It sounds like I might be going to the race gas mixture. Could the main jet be the cause of most of the spooge out of the tail pipe?
Frank, I know Scott Summers sales all kinds of stuff for those big red bikes. Try and locate his web site and see what he has to offer.
Thanks for the info. I have been reading some of your stuff on the Holeshot forum. I have not messed with the main jet yet but it is next on the list. I took your idea on the needle clip and raised it one notch tonight. Got dark before I had a chance to try it.I plan on purchasing a few other needles to try out also. It sounds like I might be going to the race gas mixture. Could the main jet be the cause of most of the spooge out of the tail pipe?
Frank, I know Scott Summers sales all kinds of stuff for those big red bikes. Try and locate his web site and see what he has to offer.
kadman,
Have you eliminated the knock sound on deceleration? I am curious since my bike has a knock sound when I let off the throttle. It started when the temps got a little cooler. The sound my bike makes is like between 1 to 3 muffled detonations when I let off the gas. It makes the motor jump when stationary. I have also been fouling the heck out of plugs as part of this problem.
BTW, do you have the idle screw turned way in? If you do then when you chop the throttle you could be pulling off of the main jet.
Have you eliminated the knock sound on deceleration? I am curious since my bike has a knock sound when I let off the throttle. It started when the temps got a little cooler. The sound my bike makes is like between 1 to 3 muffled detonations when I let off the gas. It makes the motor jump when stationary. I have also been fouling the heck out of plugs as part of this problem.
BTW, do you have the idle screw turned way in? If you do then when you chop the throttle you could be pulling off of the main jet.
- Thread starter
- #16
Sharp,
I am currently running a 175 main,45 pilot,stock needle in the third clip, and 1.5 turns out on the air screw. The bike runs great with this set-up with only a slight knock every once in a while. I cannot find any race fuel around town here but I plan on going to a 50/50 mixture as James Dean said. I have tried everything else. I plan on playing with needle this weekend just to fine tune.We have had some real warm weather here in In. so things could change in the near future.I have never fouled a plug with this set-up.
I am currently running a 175 main,45 pilot,stock needle in the third clip, and 1.5 turns out on the air screw. The bike runs great with this set-up with only a slight knock every once in a while. I cannot find any race fuel around town here but I plan on going to a 50/50 mixture as James Dean said. I have tried everything else. I plan on playing with needle this weekend just to fine tune.We have had some real warm weather here in In. so things could change in the near future.I have never fouled a plug with this set-up.
