OPmini
moo
[HELP] new Predator 420 stalls/knocks/surging/hunts
===========[THIS THREAD IS CONTINUED HERE: https://www.diygokarts.com/vb/showthread.php?p=556436#post556436 ]============

Hi, i bought a predator 420cc engine about two months ago for my mini bike. I finally got it all put together today but when i let off the gas the engine dies. any ideas as to why? or how i can fix it? thanks
EDIT 1: heres some more helpful info: All stock except intake and exhaust. I also noticed that when you turn the choke off it dies and you can rev it up alot with the choke on half way and it takes while to warm up. After running it for a while it is very hard to start again and keep on. I noticed that it says no e85 or higher than 10% ethanol blend tomorrow ill train the tank, lines, and carb and add no ethanol fuel, since idk what blend my fuel is I usually buy the cheapest gas. Are some of these symptoms indicitive of a bad blend? I also heard some knocking before the engine killed itself
Noticed that the engine is surging too
watch the videos i think that the clutch is engaging at too low rpms ill try to trim the clutch spring today or tommorrow and see if that helps
EDIT 2: there is a bearing that holds the bell on to the body and it has 6 pads inside with a spring holding them together... so I think its a bearing drum... its not that the bearing it seizing its the spring inside the clutch is super loose causing the clutch to engage at idle, thus causing the engine to struggle to keep running when the bike is not moving, THUS causing the the engine to bog down and the governer to try to rev up CAUSING surging / hunting. AND since when the choke is on, the engine will be at lower rpms causing it to run but when you take it off choke and it revs up to idle increasing the rpms CAUSING the clutch to engage and at the same time the engine wont be able to run because the clutch wont let the engine move! EURIKA!!! I THINK I FIGURED OUT WHAT THE ISSUE IS!!!
check my other post / video out here it proves my theory of garbage clutch spring: https://www.diygokarts.com/vb/showthread.php?p=556436#post556436
link to video with problem: https://youtu.be/DegYZFIyHq8
https://youtu.be/XZxXt5qghGk
https://youtu.be/VWz0flFog58
===========[THIS THREAD IS CONTINUED HERE: https://www.diygokarts.com/vb/showthread.php?p=556436#post556436 ]============

Hi, i bought a predator 420cc engine about two months ago for my mini bike. I finally got it all put together today but when i let off the gas the engine dies. any ideas as to why? or how i can fix it? thanks
EDIT 1: heres some more helpful info: All stock except intake and exhaust. I also noticed that when you turn the choke off it dies and you can rev it up alot with the choke on half way and it takes while to warm up. After running it for a while it is very hard to start again and keep on. I noticed that it says no e85 or higher than 10% ethanol blend tomorrow ill train the tank, lines, and carb and add no ethanol fuel, since idk what blend my fuel is I usually buy the cheapest gas. Are some of these symptoms indicitive of a bad blend? I also heard some knocking before the engine killed itself
Noticed that the engine is surging too
watch the videos i think that the clutch is engaging at too low rpms ill try to trim the clutch spring today or tommorrow and see if that helps
EDIT 2: there is a bearing that holds the bell on to the body and it has 6 pads inside with a spring holding them together... so I think its a bearing drum... its not that the bearing it seizing its the spring inside the clutch is super loose causing the clutch to engage at idle, thus causing the engine to struggle to keep running when the bike is not moving, THUS causing the the engine to bog down and the governer to try to rev up CAUSING surging / hunting. AND since when the choke is on, the engine will be at lower rpms causing it to run but when you take it off choke and it revs up to idle increasing the rpms CAUSING the clutch to engage and at the same time the engine wont be able to run because the clutch wont let the engine move! EURIKA!!! I THINK I FIGURED OUT WHAT THE ISSUE IS!!!
check my other post / video out here it proves my theory of garbage clutch spring: https://www.diygokarts.com/vb/showthread.php?p=556436#post556436
link to video with problem: https://youtu.be/DegYZFIyHq8
https://youtu.be/XZxXt5qghGk
https://youtu.be/VWz0flFog58