I have a 94 kodiak that has been missing when i bring it up to full idle. this continues for a while then resumes normal operation. i cleaned the carb, replaced the plug and replaced the air filter. while I was cleaning the carb, I noticed that the part between the carb and engine that supplies gas to the combustion chamber, (the book calls it the Intake manifold and parts websites, i think, call it the carbuerater joint?) is loose and sloppy. the carb is just hanging there and bouncing around which didnt seem right to me and the carb joint or intake manifold, whatever, is in two peices a piece that connects with a flange to the carb and a flange to the engine. the are connected by a thin pice of rubber but it doesnt make a seal between the two. now obviously you have realized I dont know much about this stuff, but it seems to me that is this is not airtight, air will be sucked into the head and is likely to be causing my problem. I would like to order the part but it is 50 bucks and I wanna make sure it needs to be replaced first. (the yamaha dealer wants 60 bucks just to look at it plus parts and labor. Any thoughts? I would be thankful for any help you could give me and please describe this part and what it does and wether it needs to be airtight and sealed.
thanks
John Thompson

 

Thats a pretty common problem. If its sucking air it will make your mixture lean. I think Yamaha calls it a carb joint. We always called it the intake on the Harleys. Anyway a way you can see if its leaking (sucking air) is to spray around the joint with starting fluid while its idling. If it revs up you can tell it sucked the staring fluid in. Those carb joints are high I don't blame you for wanting to make sure before you buy one.
There not that hard to change. $60 to look at it? I believe I'd try to fix it myself.

 

Shastadog is right,,,The rubber boot can also be cracked due to age....