ATV Mechanic/Help in Tucson???

[PelaPapas]

I cannot get this quad to run properly. 2006 Yamaha Bruin - It starts and idles perfect but after 1/2 throttle it starts to bogg and loses power.

 

Just got it a few weeks ago from a couple who bought it new and had been sitting in the garage for the last 4 years. They bought a new battery, had carb rebuilt and new spark plug before putting it up for sale. The thing starts and idles perfect and takes off good, but as soon as you give it more throttle (past half) it starts to bogg down.

 

I have completely gone through it all. I've changed all fluids/oils, spark plug change, ran a little seafoam in the fuel, tried adjusting the air/fuel screw, tried running it without air bow lid, etc. Nothing has worked.

 

Last night I took off the carb bowl to check the jets. Everything seemed to be good to go. There was the slightest amount of dirt at the bottom of the bowl, but for the most part it was all clean. I removed the main jet (size 60) and shot it with some compressed air. I tried to remove the pilot jet (size 94)but it was really on there tight. When I tried to remove it with a flat head screwdriver, the brass seemed like it was going to strip. So I didn't remove it and left it as is. I didn't want to chance it and break the head off.

 

I'm not sure what else is left to do. Seemed like it would be an easy fix, when I had my Banshee that was a very touchy machine and could get it running perfect . Now that I have a simple 4-stroke I can't figure out this dang thing! I'm almost positive that it's not getting enough gas in the bowl, so when I try to give it gas/throttle there's not enough gas to get it to move. Maybe the float needs adjusting or bigger main jet?

 

If anybody here in the Tucson area knows how to work on these more in depth please let me know. Message me and let me know your asking price. Thank you...

[ivhunter]

I would try and get that jet off that might be your prob, after cleaning the whole carb and that's your only thing that hasn't been cleaned I would want to check that. Did you do the ole' guitar string through jet holes thing... good luck

[PelaPapas]

I would try and get that jet off that might be your prob, after cleaning the whole carb and that's your only thing that hasn't been cleaned I would want to check that. Did you do the ole' guitar string through jet holes thing... good luck

 

No I didn't do the guitar string trick. Didn't have any on hand. Yeah it was weird that the pilot jet was on there really tight. I didn't want to break off the head!

[More D]

Air filter?

[PelaPapas]

Air filter is clean and like new.

[trufletch]

You said you changed fluids and ran some Sea foam. Did you drain the old gas out and replace with fresh? 4 year old gas will cause all kinds of issues.

[PelaPapas]

You said you changed fluids and ran some Sea foam. Did you drain the old gas out and replace with fresh? 4 year old gas will cause all kinds of issues.

 

 

Yes I did drain all old fuel. I figured out the problem and now it runs perfect! Thanks to all for the info/input.

[Arizona Griz]

So what was the culprit?

[PelaPapas]

I went online to see how the carb was put together. Turns out whoever the previous owners had the carb rebuilt by had put the main jet (#94) and the pilot jet (#60) in the wrong spots. So I just switched them and the bike runs prefect. So being that the #94 jet was in the pilot jet position it wasn't getting enough fuel in the Carb when given full throttle. It runs like new now.