4 stroke doesn't want to stay running /power lag, hesitation.

Bradyb123

New Member
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8:39 AM
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Aug 14, 2021
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Hey everyone, this is my first time posting, and I'm new to these bikes and their centrifugal clutch system. So we picked up a 4 stroke from someone online who built this bike from scratch, but definitely spend some time on it. Unfortunately that means I can't find much info about it. It ran fine for a while 9 months or so, but then all of a sudden started having some weird problems. So the rear tire spun out of control on start up, it just kept going faster and faster. Pretty wild to see. So I did some research, and learned it was probably the clutch catching the bell. (Forgive me if the terms are wrong) so I pulled it off, greased it up, added a washer Infront of the clutch, behind the bell, and that seemed to help a bit. But now it's having a problem where it feels like it's slipping, almost like it's bogging. I can't wrap my head around what it could be. It was dropped a month ago, the dog jumped up on my girlfriend and she fell over, and I think that's when the problems started. I've included some pictures that might be helpful to someone smarter than me. And insight would be amazing, and I'll try to respond as fast as I can. Thank you so much in advance!
 

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Chainlube- Thank you for the suggestion! I'll move that tensioner, and adjust the carb. What kind of picture did you want? I have the stills from my first post with the cover and bell off.

Wrench- I'll go ahead and adjust the carb. As far as the clutch goes, do you think I should purchase a new one? Any suggestions?

Sidewinder Jerry- that's a great idea, is install pretty straightforward?

Thank you guys again. I really appreciate the info and helping me track down what the issues are.
 
Chainlube- Thank you for the suggestion! I'll move that tensioner, and adjust the carb. What kind of picture did you want? I have the stills from my first post with the cover and bell off.

Wrench- I'll go ahead and adjust the carb. As far as the clutch goes, do you think I should purchase a new one? Any suggestions?

Sidewinder Jerry- that's a great idea, is install pretty straightforward?

Thank you guys again. I really appreciate the info and helping me track down what the issues are.
I just wanted to see how much sag you had in your chain.
 
Chainlube- Thank you for the suggestion! I'll move that tensioner, and adjust the carb. What kind of picture did you want? I have the stills from my first post with the cover and bell off.

Wrench- I'll go ahead and adjust the carb. As far as the clutch goes, do you think I should purchase a new one? Any suggestions?

Sidewinder Jerry- that's a great idea, is install pretty straightforward?

Thank you guys again. I really appreciate the info and helping me track down what the issues are.
Just wind the meter wire around the spark plug wire; use a zip tie to hold the meter wire in place.
 
Wrench- I'll go ahead and adjust the carb. As far as the clutch goes, do you think I should purchase a new one? Any suggestions?
A clutch don't cost that much. I know there are a few different clutches for your engine, but I don't have an engine like yours and IDK what clutch would be the best to recommend.
Maybe another Member will chime in shortly with a clutch recommendation for ya.
 
https://www.ebay.com/itm/1439377566...d=&campid=5338458686&toolid=10001&mpt=3232705

The above link is for a replacement clutch for your engine. It's just like mine. The clutch for your 15mm straight shaft is different from the ones you'll see for a tapered shaft engine. I see nothing wrong with your clutch lining or the clutch bell and I can not imagine that the springs have lost their tension with all that lining remaining. I think you'll find after you turn down your idle everything will be fine. I followed @Deleted Member 4613 directions and replaced my stock bushing with an Oilite version. Either way make sure your clutch bell spins freely with the belt removed and the engine off. There should be just a little end play (in and out movement) and you should not hear any rubbing between the bell and the case of the engine.
 
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Alright, so I think I solved it. The idle but was all the way out, and it was still revving way too high, like you saw in the video. I took a video to show you guys too, but I think when it fell the nut connecting the throttle cable (green circle) loosened itself up, so I just had to tighten it back up into place and pull the little throttle lever (red circle) on the carb closer in. I'm not sure if this makes sense, I attached a picture for a visual. Seems to run just fine now. Now I just need that Oilite bushing.

Thanks so much for helping me narrow down what it could be. I really appreciate it!
 

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