Kill Switch Won't Work When The Engine Runs Aaway

[yuckfoo]

air leak, you're running with an air leak

STOP RIDING IT TILL YOU FIND THE LEAK OR YOU WILL KILL IT. just saying.

Ok. But I can't find an air leak. I've checked twice. I don't know how to check for a case leak. No one seems to be able to tell me how. All I hear is "behind the magneto cover" and "behind the clutch cover. If any of you like to make instructional videos well then, here's a great topic. You'll be the only person in the universe to have done so.

 

[yuckfoo]

air leak, you're running with an air leak

STOP RIDING IT TILL YOU FIND THE LEAK OR YOU WILL KILL IT. just saying.

And for every two people that say it's lean another one will say it's rich. But this kind of stupid crap always happens to me. There's no way I'd ever get the engine that is good enough to run without the most impossible to fix problem. If I drop a screw it doesn't land on the floor. It hits the floor, bounces, rolls along for 3 feet, hops over a shoe and goes under the fridge. Nothing is ever simple.

 

[yuckfoo]

The kill switch not always working would have nothing to do directly with an air leak in the carburetor. In directly the high rev could be causing increased frame vibration which in turn could be causing loss of the ground contact to the kill switch.

Here's how I fixed the issue when it happened to me. I used a self tapping screw through the clamp and into the handlebar. This served two purposes.
It fixed the grounding issue and helped keep the switch held in one place.

In the video I saw on the motorcycle he said the kill switch didn't work because the engine (or part of it, or the plug) was so hot it was dieseling.

 

[Sidewinder Jerry]

In the video I saw on the motorcycle he said the kill switch didn't work because the engine (or part of it, or the plug) was so hot it was dieseling.

More often than not the simple solution is the solution. Try running a self tapping screw through the clamp and into the handlebar. I'd say there's a 95% chance that'll fix your kill switch issue.

If the smoke trick doesn't revel any leaks here's a couple of videos on the principals of adjusting air flow in a motorized bicycle carburetor. A techometer will help you really fine tune it.

Here's a couple of videos

 

[yuckfoo]

More often than not the simple solution is the solution. Try running a self tapping screw through the clamp and into the handlebar. I'd say there's a 95% chance that'll fix your kill switch issue.

If the smoke trick doesn't revel any leaks here's a couple of videos on the principals of adjusting air flow in a motorized bicycle carburetor. A techometer will help you really fine tune it.

Here's a couple of videos

Thanks!

 

[Greg58]

Here’s the how to.

Breaking Down a China HT Engine in PICTURES

I have made a 59 photo tutorial (each and every step) on how to break down a China 2 stroke 80cc (49cc same). The pics are located here: https://motoredbikes.com/media/albums/teardown-chinese-ht-49-80cc-engine.808/ Text description for the pics is below: Photo 1 of 59 Remove engine from...

motoredbikes.com

 

[Karl Snarl]

Ok. But I can't find an air leak. I've checked twice. I don't know how to check for a case leak. No one seems to be able to tell me how. All I hear is "behind the magneto cover" and "behind the clutch cover. If any of you like to make instructional videos well then, here's a great topic. You'll be the only person in the universe to have done so.

Mapp torch, same way you checked the intake and case gaskets. Just take covers off. Sometimes theres oil, sometimes it hasn't creeped out yet. If it hasn't creeped out, thats good to catch it before it goes all the way.

 

[Greg58]

The way I’ve found a blown seal is evidence of fuel in the magneto area, I blew two seals due to worn crankshaft bearings. I’m not saying that’s what you have but fuel where it shouldn’t be is a sign.

 

[yuckfoo]

The way I’ve found a blown seal is evidence of fuel in the magneto area, I blew two seals due to worn crankshaft bearings. I’m not saying that’s what you have but fuel where it shouldn’t be is a sign.

Thanks. Opened the magneto cover, it's clean as a whistle. I'll still test it though next time I start it.

 

[Karl Snarl]

Thanks. Opened the magneto cover, it's clean as a whistle. I'll still test it though next time I start it.

So whats the problem now? Your plug is looking pretty good. Is it still lean surging?