I have a 2004 Vinson that will only start and only stay running if it is fully choked. If I reduce the choke at all it dies. If I give it any throttle whatsoever, it dies. Also, when it is running it is not idling very high at all. It sounds to me like it is idling a normal un-choked idle instead of the increased RPM you should have fully choked. The bike has sat up for awhile, probably 5 months but ran just fine last time I rode it. I replaced the plug and I have taken the carb apart twice and went through it with carb cleaner. I also checked the fuel valve strainer for grit and blew it out with some air even though it was very clean looking.

I need some expertise here. What do I try next? Carb rebuild kit? Also, when I took the carb apart the first time I got a little sloppy and didn't keep track of which jet came out of which spot. I'm worried that I may have switched the main jet and idle jets. Can anyone give me the size #'s for each one or tell me which jet has the bigger hole so I can check mine to be sure I've re-assembled it properly.

I've been messing with this thing a bunch lately and I could really use some help. I hate to even look at it in the garage right now I'm so frustrated. LOL

Thanks very much in advance!!!

 

I'm not familiar with your exact carb, but with all the carbs I've seen, it's almost impossible to put the jets in the wrong holes.
I know you prolly looked, but I've had mouse nests in the air intake (after sitting) really mess things up.

 

I had a similar situation as yours. It wasn't enough to remove and spray out the jets. I had to get a thin wire and ream out crud out of the jet. It's a small hole and it may appear to be clean (because you can see the carb cleaner spraying through the jet). It may still have crud clogging it.

Once I did that, it runs like a champ now.

 

Poolsean is right, generally their is crud in the idle circuit. I generally cut me a piece of wire that is multistrian and remove a single wire to run thru the passages. Generally too, the main jet is much bigger, remember it has a rod that runs to it.

 

u may need 2 check intake/exhaust valves

 

what works really great in cleaning out carbs is torch cleaning tool that you get at welding supply store I keep one in my tool bag

 

I'll give that a shot. I admit that I haven't run anything through the jets like that. Hope I get the same outcome as you did.

To the previous post about reversing the jets, it is absolutely possible to do it on this model carb. The jets will screw into either hole.

Thanks for the help, I'll keep you guys posted on what happens when I run some wire through it. I think I could take this carb apart and put it back together blindfolded now. LOL

 

UPDATE: I went ahead and bought a rebuild kit. I decided that if I must tear it down once again I wasn't leaving anything to chance, namely my lack of cleaning skills. Anyway, started right up and after adjusting the idle speed and a minor tweak on the mixture screw, she runs fine. Ok, here is the but...it didn't have a lot of fuel in it after i drained the tank and i only put in a small amount of fresh gas in so I had it in reserve to start it and have it run. When I added some gas I switched to on and within a few seconds it died. Tried it a couple of times and same thing. If I leave it in reserve it runs like a champ. The fuel valve is clean, I blew it out with compressed air and it looked spotless anyway.

Any ideas why it runs in reserve but dies if I have the fuel tank in the on position?

 

Try it on PRI. your petcock isn't working or it has no vacuum to it. They work on vacuum once the engine is started.

 

Here is a instruction link to clean a carb next time. It a slide carb but the principles are the same.

Disassembly and Cleaning of a Mikuni Round slide Carburetor