Question regarding running idle and on choke

[fbrillou]

Question regarding running idle and on choke, new issue page 2

Hi,

Yesterday I bought my '05 Raptor 350. I had already looked at the bike last week, but it wouldn't start then. The previous owner had it checked out and it turned out to be a dirty carburetor. Yesterday when I picked it up, I noticed that when it was running on choke, it seemed as if it was running full throttle. Off choke, it didn't idle properly and would stall. Full throttle it runs fine, lots of power. I've already had a good read around the internet and have come to the conclusion that it could be a clogged pilot jet. However, I would like some second opinions to wether my assumptions are right.
Furthermore, it seems that the clutch handle engages the clutch only when it's almost completely let out, yet when I put it in gear with the clutch disengaged, it sometimes lurches ahead a little bit, as if the clutch isn't fully disengaged. This is however when the engine is still cold. I've also looked for answers for this and have read that this seems to be perfectly normal. Yet again, I'd just like to be sure that my conclusions are correct.

Cheers,

Frederic

 

[Beastmode17]

Take your carb off and clean it very good, Over time the jets can get gummed up, if had been sitting for awhile. Is the quad stock?? Have you tried adjusting your clutch??

 

[fbrillou]

Thank you for the quick reply. I presume the quad is stock, the previous owner was the second owner and he hasn't changed anything on the bike as far as i know. I'll go ahead and clean the carburetor out this evening, I guess they forgot to clean the pilot jet when they cleaned the carburetor a few days ago. The quad had been sitting for about 6 months.
I haven't adjusted the clutch yet, will have a look around for a tutorial and do that as well this evening.

Cheers,

Frederic

 

[CJCaldie]

clutch adjustments are pretty easy. the cable sounds too loose. if i had a carb sitting for 6 months and was to only clean one thing it would be the pilot jet every time. its the smallest jet and can gum up pretty quick. good practice: when your going to let the bike sit for some time or you dont know when your going to run it next, turn the fuel petcock off and let it run at idle until it dies. this ensures you dont have any gas just sitting in that jet to potentially cause you problems later on

 

[fbrillou]

Thank you for the input, I will definately do that if I need to let it sit for a while.
Will have a look at that pilot jet, I presume I can reach it without taking the carburetor off the bike or would that be too difficult?
Regarding the very high engine speed when on choke, could that also be caused by a clogged pilot jet?

Cheers,

Frederic

 

[YAMAHAULER]

It should idle high on choke
as for not idling when off choke have you tried turning up the idle screw?

 

[fbrillou]

I have not been able to look at adjusting the idle screw yet.
I am aware that it should idle a bit higher when on choke, but with my Raptor it sounds as if it's almost running full throttle.

Cheers,

Frederic

 

[jeffsyfm350x]

I have not been able to look at adjusting the idle screw yet.
I am aware that it should idle a bit higher when on choke, but with my Raptor it sounds as if it's almost running full throttle.

Cheers,

Frederic

The high idle is most of the time caused by air leaks check you carb boot for rips and make sure its tight when you pit it back toghether 90% of the time thats the problem..

 

[fbrillou]

Will check that as well, thank you for the tip!

Cheers,

Frederic

 

[fbrillou]

Right, status report.

Dismantled the carburetor, cleaned the pilot jet. Made it run a bit better, but then I discovered that the engine idle speed screw was turned up way to high. I set it lower and I achieved a more stable idle. Afterwards, when it was cold, it fired up nicely, but the idle still wasn't stable. I have checked the carb boot for rips, but couldn't find any. Also I made sure that it was snugly tightened. Went out for a run and when starting it up on choke, it still sounds as if its being revved high, yet that was not the case. I also noticed the header was glowing red. I've read that that means that it is running lean, however there are no mods that I can see. Do I need to adjust the fuel screw? If so I will have a go at that tomorrow, maybe it will resolve the rough idle and high revving engine on choke.

Cheers,

Frederic

 

[nukacola]

What are your jet sizes? If you're running lean don't run it too much!

 

[fbrillou]

I don't have a clue what size jets I am running, I presume the standard jets. Previous owner has been running it like this for a while already, says he never had trouble. But maybe the guy that cleaned the carburetor for him changed some settings, because if it were running like this when he had it, he surely must have noticed.
And when I say the idle speed setting was way too high, I had to turn it down at least 1 full rotation (probably more), after which the bike started idling better.
Is it also possible that all forementioned problems can be attributed to the old fuel still being in the tank? It is still 3/4 full and I haven't put any new fuel in yet.

Cheers,

Frederic

EDIT: I should clarify that it was only the first 2-3 inches of the header that was glowing and I could only see it at night.

EDIT 2: Also, would it be any use that I video the bike idling? Maybe it will be easier for you guys to figure out if I'm doing something wrong. I'll also get a picture of the header glowing tonight then.

EDIT 3: Also, sometimes, not all the time, it will idle at higher rpm without anything special happening. And sometimes it will take a fraction of a second to return to idle after it's been revved. Any pointers?

 

[jeffsyfm350x]

When it revs high with the choke on that means its time to turn the choke of its like a alarm.. Also the header getting red at idle is pretty normal when at idle they run lean at idle you can adjust the air screw out a 1/4 turn see if that helps.. As for the gas I'd get rid of it and add a filter to your fuel line and put fresh gas in that should help with the rough idle take it for a ride and check to see if its idles ok..

 

[fbrillou]

Ok will do that, thanks.
Also, sorry for the numerous questions, does anyone have an idea how to fix the fuel petcock? I turned it to the off setting and petrol was still running from the fuel hose when I removed it from the carburetor yesterday.

Cheers,

Frederic

 

[alex456123]

Replace it... That's the only way to fix it lol

 

[bassfishr81]

if you need a petcock i have one

 

[fbrillou]

After playing around with the fuel screw, I managed to get it purring nicely. Thanks for all the advice guys!
Thank you for the offer, but I think it would be pricey trying to send it over here.

Cheers,

Frederic

 

[jeffsyfm350x]

After playing around with the fuel screw, I managed to get it purring nicely. Thanks for all the advice guys!
Thank you for the offer, but I think it would be pricey trying to send it over here.

Cheers,

Frederic

Your very welcome..:tup:Glad to hear you got it running right..

 

[JupiterWarrior]

Where is the "fuel screw" on my 1989 exactly?

 

[fbrillou]

The fuel screw should be on the underside of the carburetor near the front of the carburetor, at least it was on my Raptor.

I have a new issue at the moment. Since a few days the Raptor has developed an intermittent rattle near the top of the engine, but I am not sure what it could be. I've checked the cam chain, but couldn't see any issues there. I've also checked the exhaust valve, but didn't found anything wrong with that either, yet I didn't have feeler gauges on hand to check it thouroughly, nor did I have the time to check the intake valve. I made a video of the sound, maybe someone knows what it could be?

Another issue is that the engine has cut out on me 2 times when I was going full chat in 6th gear and it would not immediately start back up again. Anyone had this before?

http://www.youtube.com/watch?v=Ae89hwV3L00