On my 2003 ds650 there is some kind of serious problem i need some help with if anyone has some answers it wuld be a big help.

anyway i have a 2003 ds 650 baja wiht a hmf slip on exhaust, and a KnN filter wiht a dynojet jet kit.
i am running a 180 main jet wiht the needle in the second position for about 3000t in
elevation and the fuel mixture screw is about 1 3/4 out. And the problem is that once i get into 5th gear it doesnt rev much past 5000rpm even after i put a 15 tooth front sproket on it didnt seem the change that problem. i have 22 inch tires on the rear

i need some help if anyone has the answeres thx alot

 

I can't remember what the dynojet jetting is. You may want to spend a few bucks and take it to a dyno to make sure you are properly tuned.

 

I am just guessing but your mainjet sounds too big. At that elevation I would have expected something more like a 160 to 170 with those mods. I also would have expected to hear that the needle was in the 3rd position.

Just a guess with very little info................

Good luck[img]i/expressions/face-icon-small-wink.gif[/img][img]i/expressions/face-icon-small-smile.gif[/img]

 

Actually the dynojet jets are smaller, so you will need larger numbered jets. Nuts right about the stock jetting. Does this only do this in fifth, and does it run up fine in all the other gears? And when it stops pulling, does it make any strange sounds? And when you let off does it make any strange sounds?

 

Thanks Viper. I have never used dynojet. I will remember that.[img]i/expressions/face-icon-small-wink.gif[/img]

 

yeah only in 5th and no, no weird sounds and thanks for the info

 

No weird sounds eh? Hmmm......you will need to run it again and check your plugs. Make sure to check both plugs though. Then let us know.
I can only guess it is jetting as it runs up in the other gears, it does it quickly and does not stay there very long. So it doesnt have enough time to load up. It sounds rich to me though.

 

i have recently check the plugs only tho outside one tho its was a nice tan color

 

Did you check it right after you ran it at full throttle, or did you let it idle down and drive back to the truck and then check it?

Also, are you saying the clip for the needle is in the second groove from the top? Or the bottom?

 

If topend jetting is off and causing a lack of power, it can easily be off just enough to be virtually undetectable in the first 3 gears, slower reving in the top of 4th and simply won't rev out in 5th.

I would run it wide open in fifth until the revs stop climbing. Let it run like that for a few seconds then pull in the clutch and kill the motor. Coast to a stop and do a plug check. That should tell you if it is a main jet issue.

Oops, sorry Jed. Didn't know you were already on the plug check.lol

Do what Jed says![img]i/expressions/face-icon-small-smile.gif[/img]