I'm having a problem with my 99 Magnum 500....It starts fine cold (with the choke on) but within 15 seconds of running it starts to run rough and bog . So then i turn the choke off and the idle is so low it almost stalls.Once the quad is warm it runs perfect...It does'nt skip a beat ... the idle comes up and is smooth . I've emailed dyno jet and they told me to richen it up .....I tried that ..still when it's cold it does'nt idle proper. Also when it is cold it bogs a bit just off idle.

Any help or thoughts would be great!!!!!

Chris
1999 Magnum 500
K&N
Dyno jet

 

i think that you are running way too lean. im having the same problem with my 400EX. except mine wont even start. [img]i/expressions/face-icon-small-frown.gif[/img]

 

might be your m0ds doing it to with the k&n filter...............making it run too lean.........i've had 3 magnums and used another for a while and never have had a problem like that but my machines have all been left stock to so that might have somthing to do with it.........by the way have you had any problems with your magnum??????????

 

Well steve , that's what dynojet keeps on telling me ....Acording to the kit i should have installed a 155 main jet (wich i did to start)..and the jet needle on the 3rd groove(wich i also did)...and finnaly the mixture screw 3 turns out..

Currently there is a 160 main installed ....4th groove on the jet needle and 3 1/2 turns out on the mixture screw..

Like i said ..when it is warm it's fine (all speeds)

Do i unscrew the mixture screw some more??????????????????????????????????? I don't know...I guess it might be worth a try(TOO BAD THE MIXTURE SCREW IS SO HARD TO GET TOO)

Buy the way my float level is perfect ...I checked many times

CHRIS

 

Hey polarisman3....You know what ....I just purched that filter in the summer time...this is my first winter with it ...Never had too start it in the cold before ...you could be right...like i said in my last reply , i will richen it up...and see what happens

As for problems ....so far 3 besides regular matinence(Brakes..front end ...fluids)

1st ...The carb problem
2nd....Starting too get major vibrations at high speeds(70- 95 km)...And it's not a tire problem..It's almost like a pulsating vibration????
3rd.....My belt cover is starting too rub sometimes...If you pull out on it , it goes away....Might be warped - i don't know?????

Over all the machine is great...No break downs at all ...2300 miles on the machine
When we go too the rockies i ride it hard....GIDDY UP

 

When is the last time you checked your valve adjustment? On my Grizzly, when the intake valves get too tight (about every 30 hours), it won't idle at all until warmed up. You have to sit there and keep pressure on the throttle so it'll idle.

So... check your valves, that might be it.

Rob

 

Just had them adjusted 150 miles ago........Any other suggestions?????

Chris