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05 125 Running Backwards


the artist formerly known as ish
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05 GG 125 pro, running backwards, things tested so far and not worked.

All electrics changed over from a known good runner, stator plate, flywheel,

also took key off crank shaft and repositioned flywheel on shaft to try change timing still same result, anyone any idea what the cause could be.

Could the crank be out of time ? only thing that has not been changed and tested yet ?

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Could the mounts for the ignition plate be drilled / marked wrong? The case side half.

It should be a timing issue, and I would guess that something in the basic setup is wrong.

can you see, read, tell when it triggers visually? Then check a known good one for comparison? Do an actual meausurment at the head type reading when it triggers?

Do you still have my work e-mail?

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John,

Assuming the bike ran correctly once upon a time: I am not familiar with this particular model but two strokes in general can run in either direction forward or back ward. If the ignition timing is set to fire before top dead center BTDC then it should run forward. If after (ATDC) it will run the other way. With a timing light and the bike running you should be able to see where the ignition is firing. However, you evidently have a bike to

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Frank, I love your sign on name..... Knew who it was the minute I saw it.

I think Ish is saying it has always done it from new, and has changed all the electrics, which makes me lean too it may be a manufacturing error in the case half itself.

Ish is a dealer, not sure if he handles GG though.

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I would sure want to hook up a timing light to establish the actual spark timing - regardless of what the timing marks "say". On vintage (points/magneto) systems on a two-stroke, either severely advanced timing (say 30-35 degrees BTDC) or severely retarded ignition timing (say 10-15 degrees BTDC) seem to result in an engine which is more willing to run backwards than a properly timed engine.

In my experience, strongly advanced timing often leads to running backwards through the following process:

1) a less than energetic kick brings the piston up relatively slowly

2) spark happens well before TDC and builds enough pressure to reverse the piston travel before it reaches TDC. Voila, engine is running backwards! (with spark timing now @ 30 some degrees After TDC)

Ed

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Ish,

If it has a typical stator plate with 3 screws, be sure it is oriented properly and not 120 deg out of time.

All else being correct, the magnet may have slipped in the flywheel causing an incorrect trigger point. That's all I can think of.

When are you going to answer my question about the spring?

:lol: MC

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Ish,

If it has a typical stator plate with 3 screws, be sure it is oriented properly and not 120 deg out of time.

All else being correct, the magnet may have slipped in the flywheel causing an incorrect trigger point. That's all I can think of.

When are you going to answer my question about the spring?

:lol: MC

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