[02Raptor660R]

ok so heres the story. i have a 2002 660R. Jetted air intake. Carbs. white bros exhaust. i think thats all the engine mods. i havent rode the bike since summer and i went to ride today. quad wouldn't start right away so i took the air filter out and sprayed some cab cleaner and it started right up. the bike has always ran on the warm side and idled high. ive had numerous mechanics look at the bike and no one has been able to give me an answer except the bike just runs hot. so anyway i let the bike warm up for like five mins. the quad was idling higher like always. as i went to take it out, i checked to make sure my gas was on and it was but i realized my headers were glowing cherry red. like as if i took a blow torch to them and was about to weld them. never have i seen something like that before. i checked the coolant and it was full. i let the bike cool down and checked the oil and oil was fine. i did both the coolant and oil after the last time i rode in the summer. does anyone have any ideas what it can be? if anyoe wants to email me rather than post to thread my email is [email protected]

 

[wobble]

So you are concerned about the glowing headers? If so, that's normal.

 

[mtlwiz]

sounds like carb jetting to me

 

[1FST690]

pull the carbs and see what the jet sizes are. Also check to make sure that the carbs are fully seated in the boots

 

[wobble]

Didn't the early model 660s have carb boot problems?

 

[Buck]

sounds like its runnin a bit lean

 

[02Raptor660R]

So you are concerned about the glowing headers? If so, that's normal.

yea thats what i was concerned about because today is the first time its happened. the bike idols really high. and also when i engage the clutch while riding the idol spikes really high.

 

[wobble]

I think 1fst690 is on the right track. Sounds like you are sucking in air.

 

[02Raptor660R]

can the jet sizes have anything to do with how high the idol is on the bike. this is a whole new world to me because ive always rode utilities up until about a year and a half ago

 

[1FST690]

yes if its not jetted correctly it could high idle lean. It could also be 2 completely different situations 1 its actually a tad rich, and 2 the idle screw is set too high. There is only one way to find out though and that is to do some basic diagnostics. Remove the carbs, clean them thouroghly, see what it has for main jets and pilot jets. screw in the air bleeds until the seat softly counting the turns as you screw them in. then report back what you find. We can him haw all day long about what it could be but until you start at the most logical steps then we will get nowhere. Also when you remove the carbs check to make sure they are fully seated in the boots.

frank

 

[02Raptor660R]

frank,

thanks man i appreciate. ill start there and see where it takes me. i have a buddy coming home from UTI this weekend to help me out so ill relay the message to him and see what we can do with it.

PJ

 

[CUETO700R]

yes if its not jetted correctly it could high idle lean. It could also be 2 completely different situations 1 its actually a tad rich, and 2 the idle screw is set too high. There is only one way to find out though and that is to do some basic diagnostics. Remove the carbs, clean them thouroghly, see what it has for main jets and pilot jets. screw in the air bleeds until the seat softly counting the turns as you screw them in. then report back what you find. We can him haw all day long about what it could be but until you start at the most logical steps then we will get nowhere. Also when you remove the carbs check to make sure they are fully seated in the boots.

frank

100% Agreed!!:thumb: First and foremost you need those carbs out to find out whats in there jetting wise. With an exhaust and k&n you definitly need that thing jetted. Probably 145-150 setup or maybe even 150-155 on your mains and maybe even bump up your pilots. You also need to factor in if your running no air box lid or a K&N lid like I am.

Your at the right place for advice and assistance!

Good luck buddy :beerchug:

 

[1FST690]

frank,

thanks man i appreciate. ill start there and see where it takes me. i have a buddy coming home from UTI this weekend to help me out so ill relay the message to him and see what we can do with it.

PJ

No problem, let me know what ya find and we can go from there. The glowing pipe at idle does not really concern me all that much. The high idle does though. That is indicative of a lean condition. You should also pull the plug and look deep down inside where the base or the porcelin is and see what color it is. Should also look for metalic/reflective bits on the end of the plug that could indicate a lean condition also.

 

[rwcasto]

You have a vacuum leak and it is running too lean...Your Carb boots could have cracks in them, or your synchronization boot is off completely on your primary carb, check that first, but you diffidently have carb issues.

 

[02Raptor660R]

Frank and rwcasto,

thanks again so much for your help. i checked a few other forums and sure enough someone with the same bike with very similar mods is having the same exact problem. i was also reading though that because of the carbs being jetted, the regular carb boots wont hold up and can keep cracking. assuming that that's the issue do you guys recommend any aftermarket carb boots so i don't run into this problem down the road? i didn't get a chance to look at the bike yet because it was a crazy weekend but im hoping i can spend some time on it this week and confirm if a cracked carb boot is the issue or not.

PJ

 

[wobble]

My buddy ran these on his '01:

UPP Racing - Manifolds - Raptor Intake Manifold

 

[1FST690]

I run stock boots on my stock carbed bike and trinity intake/boots on my dragbike. I think it has more to do with the rubber detiriorating (sp?) over time more so than the jetting of the carbs causing the boots to fail. I know if the back of the carb isnt supported well enough, that can help speed up the cracking
:lol:

 

[02Raptor660R]

OK!!! I'm going to be extremely happy if i just figured this out!! thanks to someones post in the "HOW TO" section i found a expanded assembly of my quad and i think im missing a part and im not sure but i think it would explain my vacuum leak and like you all said make my bike run too lean. in the picture im missing parts numbers 10 & 22. These are the air tubes that lead from the carbs to the air box. i have the ones for the left side however im missing the ones on the right. could this be my problem???!!!

Here is the link to the whole expanded assembly
Ronayers.com Fiche Desktop All-Terrain Vehicle (ATV) Yamaha 2002 Raptor 660 INTAKE

 

[02Raptor660R]

OK!!! I'm going to be extremely happy if i just figured this out!! thanks to someones post in the "HOW TO" section i found a expanded assembly of my quad and i think im missing a part and im not sure but i think it would explain my vacuum leak and like you all said make my bike run too lean. in the picture im missing parts numbers 10 & 22. These are the air tubes that lead from the carbs to the air box. i have the ones for the left side however im missing the ones on the right. could this be my problem???!!!

Here is the link to the whole expanded assembly
Ronayers.com Fiche Desktop All-Terrain Vehicle (ATV) Yamaha 2002 Raptor 660 INTAKE

anyone think this could be the problem??

 

[1FST690]

could be part of it. If im not mistaken that is the tube that activates the vacuum slide. If the slide doesnt go up it wont draw as much fuel out of that carb