2008 Yamaha Zuma Losing Power at 15 mph

Old 03-25-15, 02:51 PM
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2008 Yamaha Zuma Losing Power at 15 mph

Hi All,

First post so bear with me.. I'm having issues with my 50 cc 2008 yamaha zuma, it has 1,960 miles on it. I am not the first owner, I bought it off of a friend at around 1,400 to 1,500 miles on it. All of the sudden while riding it today the engine would cut power and start coasting if I pulled the throttle more than half of its full rotation. I find that it happens quicker when I'm riding up a hill. I found that if I fully rev the engine long enough, about 4 to 5 seconds or so the engine completely dies. It doesn't have issues starting back up after that however. I also have to kick-start it to start it up, my solenoid or something is shot, however I purchased it this way and I believe the issue is unrelated. If anyone has any ideas they are greatly appreciated.

It appears that I've posted this in Cars, SUVs, Trucks, etc.. Sorry guys.
Old 03-25-15, 08:05 PM
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Sounds like a carburetor issue to me. Might be a bit of water in it.
Old 03-26-15, 12:22 AM
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Thanks for the reply!

How exactly would I go about fixing this issue? I'm not really sure where to begin. If I were to clean out the carb, what would I use to clean it? Anyone with experience on this issue?

Old 03-26-15, 07:44 AM
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First make sure that when you add gas to your machine that it's fresh and clean. Small engines have small carburetors with lots of very tiny passages, jets and orifices. It doesn't take much to clog something.

Shine a flashlight into the fuel tank. How does the bottom look? If you see dirt, rust or other crud in the bottom this would be a good time to remove it and give it a thorough cleaning.

The carburetor will need to be removed from the engine in order to clean it. Then it will need to be disassembled at least partially and cleaned. If you are not comfortable taking the carb apart or don't have the tools almost anybody that works on small engines should be able to do it for you.

Old 03-26-15, 08:21 AM
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Sounds like a plugged main jet.
Remove fuel bowl & gasket. Spray carb cleaner in the bowl & wipe with clean paper towel. Slide out the float pivot pin (20) and remove the float (19) and valve (18). There may be a fine wire retainer holding the valve to the float--don't lose it. You should now be able to see the jets. Using the straw that comes on a can of carb cleaner spray cleaner into each jet and any other orifices you find. Wear safety glasses because sometimes the spray will shoot back at you or come out of a different port right in your face! Gently run a thin tag wire (from a hang tag or stripped from a garbage bag tie) into each orifice. Spray again. Reassemble and test. In my experience with small 2-cycle engines this is usually all that's needed.

Other possibilities:
Dirty air filter.
Dirty fuel filter.
Plugged air vent in gas cap (no air in means the carb has to draw against a vacuum that builds in the tank)

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