daveyamaha
New member
i posted a thread about my sled not idling last season. i cleaned the carbs like you all said to do and it worked temporarily. when i choke the carb it runs great. as soon as i take out the choke it begins to bog and the rpms drop to zero and the engine dies. while it is doing this, if i choke it, it begins to idle up again. it hesitates a bit when i pin the throttle but it goes like hell under full accelleration. i am only having this problem when i am at idle. i have cleaned the carbs two times and they are cleaner than clean. there has to be someone out there who has had the same thing happen. i don't want to take it to the stealership so they can start from square one and charge me for everything that they decide to try to fix. please.....somebody..........anybody........give me something.............don't make me beg
I know it probably won't help, but to me it sounds like the idle circuit and/or pilot circuit has trash in it or the idle/air control adjustment screws aren't set correctly. Whatever the problem is, it's a lean idle circuit problem. Are the carburetors sync'd with eachother as well? When you cleaned the carbs, did you pull ALL the screws out and clean them along with all the jets?
Check the air jet at the mouth of the carb. They seem to get dirt in them very easily. (belt dust). I have had this happen on several 500's. 
OnDaTrail
New member
Also check your float levels. Some carbs are very finicky as to what level the fuel is in the bowl.
Illinoisff133
New member
daveyamaha said:
those sypmtoms right there are telling you that it is a pilot jet issue, whether it is clogged or not getting enough fuel to your pilot jet. your pilot jet is getting gas pulled out of it from idle to 1/2 throttle, from 1/2 to wot, your main jet is supplying the fuel, and each jet was sized from the factory to run the air/fuel as close to 14.7:1 as possible. get some yamaha combustion chamber cleaner and put some in a muffin pan and let all of your jets soak in that stuff, it comes in a yellow and black spray can. dont use the carb dip, this stuff works ten times better. soak the brass pieces in there and run a wire through everything if you have to, then rinse em off in carb cleaner, then blow them out with air, do the same to the float bowl. make sure you blow out EVERY HOLE OUT IN THE CARB!!!! the tinyest piece of junk can clog up that pilot jet. and just like OnDaTrail said, check and adjust your float heights. i think the air jet is supposed to be turned out 1.5 turns. another thing to remember when working with carbs is every 20 degrees is equal to 1 jet size bigger needed.