Jetting.....Can't get it right :(
#11
01-09-2003, 10:58 PM
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Jetting.....Can't get it right :(
Originally posted by: JSsDS
This issue comes up about twice a month on this site so you may want to do an advanced search an see what others have done. OR
Generally speaking everything posted here has truth. The only problem is, you may have something else wrong. a few questions;
1) has the problem been the same since you started troubleshooting it? (popping around 2500 rpm)
2) Will the RPM go over 2500 or does it sputter to bad to let it
3) What throttle positions does it sputter at (wide open, half-full, only part throttle)
4) Did it ever run good with the new pipe/filter or did this start since you put it on?
5) Have you tried new plugs?
6) Have your valves been checked for clearance?
7) Have you checked your intake boot for cracks?
Lots of questions but without knowing more about your situation its all a guessing game and that can get expensive for you. [img]i/expressions/face-icon-small-wink.gif[/img]
This issue comes up about twice a month on this site so you may want to do an advanced search an see what others have done. OR
Generally speaking everything posted here has truth. The only problem is, you may have something else wrong. a few questions;
1) has the problem been the same since you started troubleshooting it? (popping around 2500 rpm)
2) Will the RPM go over 2500 or does it sputter to bad to let it
3) What throttle positions does it sputter at (wide open, half-full, only part throttle)
4) Did it ever run good with the new pipe/filter or did this start since you put it on?
5) Have you tried new plugs?
6) Have your valves been checked for clearance?
7) Have you checked your intake boot for cracks?
Lots of questions but without knowing more about your situation its all a guessing game and that can get expensive for you. [img]i/expressions/face-icon-small-wink.gif[/img]
2)It does go over 2500RPM, sometimes when it pops it does it so bad the motor quits(man that does not sound good at all)
3)It sputters just as you are pressing in the gas(it doesn't take much time to hit 2500RPMs)
4)It runs pretty good right now, just the popping through the carb, I can tell there is more power with the new exhaust.
5)Had new plugs installed when pipe was installed
6)No, valves have never been checked, honestly...I've never had the 10 hr inspection done on it
7)No, I haven't checked the intake boot for cracks.....I seem the remember something about spraying WD-40 on it while it is running and see if it idles different. Is that right??
Thanx for taking the time to help me out, I should be able to mess with it tomorrow to see if I can get it right. Is it possible for the cold to be causing these problems?? How long should I let it warm up??
#12
01-09-2003, 11:05 PM
#13
01-10-2003, 08:02 PM
Jetting.....Can't get it right :(
It sounds like the jetting.
Your mechanic was half right...if you talk mikuni jets you need a 170 to 180 but dynajet numbers there jets differently so the numbers are higher for the same gas volume. The jets mentioned on this thread and the jets you have are dynajet and are correct. go with the 195 main and the clip in the 3rd groove and that should do it. Check the site that Marky posted (third post down) it has just about any piece of info you could want for the DS including checking your valves [img]i/expressions/face-icon-small-wink.gif[/img]
Your mechanic was half right...if you talk mikuni jets you need a 170 to 180 but dynajet numbers there jets differently so the numbers are higher for the same gas volume. The jets mentioned on this thread and the jets you have are dynajet and are correct. go with the 195 main and the clip in the 3rd groove and that should do it. Check the site that Marky posted (third post down) it has just about any piece of info you could want for the DS including checking your valves [img]i/expressions/face-icon-small-wink.gif[/img]
#14
01-10-2003, 08:24 PM
Jetting.....Can't get it right :(
Just one thought.
When I first jetted my raptor, one of the needles did not get seated in the slide just right and it was causing symptoms like what you describe. I have not been into the needle part of the carb on mine in awhile so I cant remember if it is the same or not. You might try double checking that the needle is seated down into the slide all the way.
From my own experience it does not seem like main jets make that big of a difference on these 4 strokes. I think your problem could be something other then the carb also. But start with the carb. also check the float and make sure it is set correct also.
I purchased the dynojet kit and in my opinion it was worth the money.
Other then that I dont know what to tell you.
When I first jetted my raptor, one of the needles did not get seated in the slide just right and it was causing symptoms like what you describe. I have not been into the needle part of the carb on mine in awhile so I cant remember if it is the same or not. You might try double checking that the needle is seated down into the slide all the way.
From my own experience it does not seem like main jets make that big of a difference on these 4 strokes. I think your problem could be something other then the carb also. But start with the carb. also check the float and make sure it is set correct also.
I purchased the dynojet kit and in my opinion it was worth the money.
Other then that I dont know what to tell you.
#15
01-12-2003, 03:16 PM
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Jetting.....Can't get it right :(
OK....installed the 195, and checked to see if the needle was setup correctly. I'm still not sure about the slide thing, guess I should get a manual someday. Under the top cap on the carb I see.... A big spring, big black rubber thing, a little plastic "cap" of some sort, a small spring under that, a small washer, clip on 3rd groove on the needle, two more 'spacers' and thats it. Which part is the slide and how can it stick at full throttle??
Ok, so I started it up and it seemed ok, but then did the same popping thing twice. So I let it warm up for a bit then I revved it up and nothing happened. I then thought maybe the supertrap setup I have on the pipe may have something to do with it so I took it off, started it up revved it for awhile, and nothing. I then put the supertrap setup back on again and it ran fine. So I'm thinking it maybe has something to do with the bike not being warmed up enough, which I don't think that should have any effect on it anyways????
What in the carb should I mess with to tune from 0-3000RPM's??? Thanx for all the help.
Ok, so I started it up and it seemed ok, but then did the same popping thing twice. So I let it warm up for a bit then I revved it up and nothing happened. I then thought maybe the supertrap setup I have on the pipe may have something to do with it so I took it off, started it up revved it for awhile, and nothing. I then put the supertrap setup back on again and it ran fine. So I'm thinking it maybe has something to do with the bike not being warmed up enough, which I don't think that should have any effect on it anyways????
What in the carb should I mess with to tune from 0-3000RPM's??? Thanx for all the help.
#16
01-12-2003, 04:39 PM
Jetting.....Can't get it right :(
It sounds like your close now. When an engine is cold it requires more fuel to run properly. This is why carbs have chokes. If you're runnin lean it will run better as it warms up. It should run good shortly after start-up - maybe 1 minute of warm up - if its jetted properly.
0-3000 rpm is your pilot circuit and the air screw. If it cannot be adjusted by turning the screw (bottom of carb body, points straight down) CCW then the pilot jet may be plugged. The pilot jet is the small jet next to the main jet.
0-3000 rpm is your pilot circuit and the air screw. If it cannot be adjusted by turning the screw (bottom of carb body, points straight down) CCW then the pilot jet may be plugged. The pilot jet is the small jet next to the main jet.
