two 440ex's, one big problem

[hotlicks]

I have a great running 440 ex and one that all of a sudden after months of great running shut down, and when I tried to turn it over killed the battery in about 10 seconds. With the battery newly charged it will not idle, but with 1/4 to full throttle runs irradically. I took everything ( coil, carb, cdi box, voltage rectifier ) off the great running bike, except for the stator, one part at a time and still get same results. Could the stator cause it not to idle and only run at high rpms, and even then when the throttle is held constant it spikes high and then low rpms erratically? Any way to test the stator? Any idea or thoughts?

Thanks for your time.

[exrider008]

when was the last time it was rebuilt? give us a little more info

[Wheelie]

Do a leakdown test.

[hotlicks]

the 440 kit is about 6 months old, and what do you mean a leak down test?

[Wheelie]

I'm bad at explaining things, but here it goes

A leak down test is injecting air into the cylinder via the spark plug hole when the piston is at TDC on the compression stroke. A leak down test will have two guages on it, one tells how many psi is injected into the cylinder, the other how much psi the cylinder holds.

If there is a leak it will be noticable/audible, whether it's through the exhaust, intake or crankcase (bad rings). Head gasket failure is another thing that will pop up.

Also, check your valve clearance before testing.

[boricua]

so basically, the leak down test will let you know if your valves and piston rings are sealing properly. i'd be willing to accept that if the rings were wasted, that it would be hard to start due to compression loss. then after it started would require some extra throttle to keep it running. also that it would perform like crap again due to loss of compression. how much can you lose before the engine loses the ability to run........:rolleyes: :confused:
however, its hard for me to fully accept that a low compression engine will idle or rev irradically......maybe on a two stroke.
wait.....you said it shut down after months of great running and when you tried to start it, it killed the battery in about 10 seconds....so your battery was low, which tells me its not being charged...at least not well enough. maybe it is your stator. isnt that what charges your battery when the motor is running?
hmm:ermm:

[dragracer101]

[i]that what charges your battery when the motor is running?
hmm:ermm: [/B]

ya i think so

[boricua]

easy tiger.....the question was rhetorical.....:blah:

[hotlicks]

I think I need to test the stator. Does anyone know how to use an ohm meter to do that?

[boricua]

i just got a repair manual....ill take a look at it and get back to you later today.......

[boricua]

did you figure it out..........

[hotlicks]

still working on it