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

 

my guess... it is in the carb...make sure you put in together right....has this quad ran good on your settings before?

 

when it was completly stock it ran like a top

 

What size was the original main jet? Putting on a slip on and just a K&N filter won't require rejetting on most machines. A full exhaust with airbox mods will require rejetting. Remember rejetting up does not create power, it just makes the fuel mixture richer, and you may have over richened it. I would put the original jets back in and try it.

 

as far as jetting goes your plugs will tell you if its running to rich by being real black. if its too rich it will be very boggy at high altitudes.

 

I would move the clip one spot to allow more air...very easy to do but a few small parts to keep an eye on (one spot toward the end with the grooves not toward the point)

 

ok thanks everyone