PLEASE HELP, engage clutch, no rotation of sproket!

[Chickenegg787]

I had my first build running good and clean for about 2 months. Went to refuel as I have done multiple times by now, but either the ratio was off or I had to wrong oil as I was experimenting which combinations would run the best. Anyways, I was on my way to a camp out so I had a pretty heavy load with me and after about 18 min into my ride (luckily I was practically there) the engine started slowing down to the point where it shut off, and when I looked down to see what was wrong, visual flames were coming out of the exhaust. At this point it was shut off and I pedaled the rest of the way.

The next morning is my issue. I went to go see if the overheating damaged anything and this is where I am at. When I pedal to get momentum to turn over the engine, everything is smooth until i engage the clutch. What happens is, my rear tire completely stops rotating and I skid until I stop. I took off the clutch plate and looked at the sprocket. I was unable to turn the nut connected to it to the point where it rotates the whole gear along with the chain as you have to do to get the chain on. I went to tighten the nut and it just keeps spinning due to the limited thread...HELP! what's going on!?!?!? the clutch sprocket doesn't rotate at all!

 

[Bikeguy Joe]

Sounds like you seized it, and then stripped the threads trying to turn it.

 

[Chickenegg787]

You say I seized it...what does that mean and can i fix it?


I defiantly didn't strip the bolt that the nut screws onto... I can see that there is just limited threading to work with and its almost as if the washer isn't thick enough? because when I tighten it down, it surpasses the threading and then rotates freely.

 

[Bikeguy Joe]

Hmmmmm can you post a photo?

By seized, I mean locked up the engine by overheating it due to too lean of a mixture.

Usually, but not always means the end.

As for the sprocket turning, you lost me there...you said the wheel locks up when you try to start it. Then you say the sprocket is turning and you are trying to tighten it....now my head hurts.

 

[Al.Fisherman]

Which nut are you talking about? The sprocket (on the clutch shaft) nut or the (large) clutch gear nut?
Remove the spark plug (I'm also afraid you toasted the engine, although repairable), and see if you can rotate the engine (crankshaft) using the nut on the magnet. Turn clockwise, and don't put a lot of pressure on the wrench/socket.
Me too.....

 

[Chickenegg787]

that would be the worst day of my life. it took so long to get it going...

I post post pictures, but Im not sure of what... it looks as though everything is the same visually.

I'll try to be a little easier to understand...I apologize for the lack of detail


the only issue I have is that the external sprocket that the chain is resting on does not rotate when the clutch is engaged. Normally, and prior to this incident, the nature of the sprocket was so that you could manually rotate it with a spark plug wrench. This is also the same method used to initially get the chain around the sprocket before you connect the master link. Now, when I try to engage it after pedaling or by manually turning it with the spark plug wrench, it doesn't rotate. When I hold the clutch lever down and the clutch is not activated, the entire system rotates freely and functionally which is how I am able to pedal around still.

Hope that helps
THANKS SO MUCH BY THE WAY

 

[Bikeguy Joe]

That's what I thought you said.

Sounds like it is seized.

 

[Al.Fisherman]

Use this link and there are the correct terms for the different parts.
http://www.bicycle-engines.com/2stroke-parts-c-4.html?osCsid=ges5a73qhdeuvshi19srjuq544

 

[Bikeguy Joe]

If you got it so hot that flames were coming out of the exhaust, I think you roasted it. (technical term)

It is likely fix-able, but you will have some work ahead of you....and some parts to buy.

 

[Chickenegg787]

I am uploading pics right now, the *drive sprocket will not rotate when the clutch lever is engaged and the *m14 nut is the nut that continually rotates when I try and tighten it down.

 

[Bikeguy Joe]

By "experimenting" with the mixtures of oil and gas, you probably ran it too lean. Does my signature take on any significance now?

 

[Bikeguy Joe]

I'm waiting for the pics, but I am still guessing you stripped the nut trying to tighten it due to the whole works being locked up solid.

 

[waistofhumanspace]

Chinagirl!

 

[Chickenegg787]

 

[Bikeguy Joe]

Have you tried removing the nut and looking at the (likely stripped) threads?

 

[Bikeguy Joe]

sounds like you seized it, and then stripped the threads trying to turn it.

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[Al.Fisherman]

I am uploading pics right now, the *drive sprocket will not rotate when the clutch lever is engaged and the *m14 nut is the nut that continually rotates when I try and tighten it down.

Sounds like a sheared key, along with possible other problems. The flames would have me concerned.

 

[Bikeguy Joe]

i'm waiting for the pics, but i am still guessing you stripped the nut trying to tighten it due to the whole works being locked up solid.

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[Chickenegg787]

this is why I don't think it is stripped. the nut just passes the threading and spins on the un-threaded portion

 

[Al.Fisherman]

If the key is stripped, and the chain installed the shaft will turn but the sprocket won't. Try adding another washer if the key is intact. Check threads in the nut.
To tighten the nut, remove the clutch cover, wedge a penny between the two gears and tighten the sprocket nut.