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Lighting and Electrical Things that go ZOT! Ignition components, batteries, lighting and accessories

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  #1  
Old 05-30-2016, 07:36 PM
Kletus Kletus is offline
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Default Anybody know anything about the magneto magnet

My engine is misfiring at mid range and high RPM's After adjusting the carb jet needle all the way up and all the way down in steps It only got worse so i returned it to the middle factory position and started looking at the magneto and CDI. The rotating magneto magnet only has magnetism on one side. One side will clasp a screwdriver bade hard to it and the other side has very little magnetism and wont hold the weight of the blade. Could this be the problem?
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  #2  
Old 05-30-2016, 07:41 PM
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Venice Motor Bikes Venice Motor Bikes is offline
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Default Re: Anybody know anything about the magneto magnet

Lets start with the basics... How new is the engine, & what gas/oil mix are you using???
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Old 05-30-2016, 07:45 PM
Kletus Kletus is offline
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Default Re: Anybody know anything about the magneto magnet

Engine is a brand new LOL,LOL,LOL gasbike GT80. Mixture is 32:1.
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Old 05-30-2016, 08:35 PM
crassius crassius is offline
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Default Re: Anybody know anything about the magneto magnet

a rare thing, but that could give a weaker than normal spark - as the rotor turns, each side adds power to the CDI for a single spark

if this is your problem, you should see harder than normal starting and better running as speed increases

gasbike *should* send you a new one if you explain it to them as you did here
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Old 05-30-2016, 08:59 PM
Kletus Kletus is offline
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Default Re: Anybody know anything about the magneto magnet

LOL, I called Gasbike and finally got through. I talked to some guy named Lorenzo. His main focus was to explain to me how they weren't responsible for diagnosis and how they had protected themselves with their terms of service. He did agree to send me a new magneto coil and magnet but did not want to listen to anything else I had to say about the problem. was really quite obnoxious and aggressive.
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Old 05-30-2016, 09:32 PM
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Venice Motor Bikes Venice Motor Bikes is offline
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Default Re: Anybody know anything about the magneto magnet

Here's a few more questions...

Describe how you mixed your 32:1 ratio?

Did you shake the gas & oil thoroughly before pouring it into the bikes tank?

What is your spark plug gap set at? (.025" is good)

I ask these questions because the simple fact that the engine is running at all is a very good sign that it's not a ignition parts problem (& might possibly be a fuel, jetting or gap issue).


Please post some pics of your setup.
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Last edited by Venice Motor Bikes; 05-30-2016 at 09:37 PM.
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Old 05-30-2016, 10:09 PM
Kletus Kletus is offline
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Default Re: Anybody know anything about the magneto magnet

I poured 4 oz. oil in the can went to the as station put in 1/2 gallon shook the can and finished putting 1 gallon total in the can. and shook it again. Thought it might be the gas but it runs ok in my string trimmer. All 5 plugs gapped at.025". Engine idles well and has strong power on start up then as RPM's increase it starts misfiring and fouls the plug. I see no evidence of head gasket or base gasket leaks. My thoughts were it was running to rich or misfiring and loading the plug up. Lowering or raising the carb jet needle made it run worse so I concluded it must be an ignition problem. If the magnet doesn't fix it my next step is to cut the cdi box from the coil and wire the ignition coil straight to the magneto. If none of this works I will order a new coil and carb from Ebay. Only problem is the wait time and I'm ready to roll now and this thing misfires so bad its embarrassing to ride it down the street.

Last edited by Kletus; 05-30-2016 at 10:15 PM.
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  #8  
Old 05-30-2016, 10:57 PM
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mogollonmonster mogollonmonster is offline
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Default Re: Anybody know anything about the magneto magnet

I would be willing to bet your main jet is too rich. This is normal. Break in your motor, then rejet. I'm with Venice on this one. My money says jetting.
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Old 05-31-2016, 01:10 AM
MEASURE TWICE MEASURE TWICE is offline
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Default Re: Anybody know anything about the magneto magnet

I know the title of this thread has not really gotten any answer unless I missed something. What I mean is although I have a Briggs 4 stroke, the Magnet is only on one side of the flywheel on it. The other side is just a mass of metal weight to balance out the flywheel. I expect these engines might be the same. Some one using these engine and have it running good would probably find that one side is a magnet an the other side is not also.

The other information that is being offered aside to help I know probably less of so see what you can find help on Carb and CDI.

MT
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  #10  
Old 05-31-2016, 05:50 AM
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Agreen Agreen is offline
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Default Re: Anybody know anything about the magneto magnet

It is most definitely too rich. The needle does not do anything for upper rpm. It's only for partial throttle transition. If it's misfiring and sounds like a machine gun at high rpm, it's doing what's called 4 stroking. You can either buy a jet kit, or drill your own. A soldering iron and elecrical solder will work to close the jet, then a set of micro bits (size 60-81) can re size it properly.
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