150cc power loss By jomama0867 (Read 853 times)

[jomama0867]

Going to work last week, I came off of the highway (55-60 MPH for about 3 miles) and stopped at the service road light. When the light changed I noticed a severe drop in power (not as much on take-off, but 10 kph to 40 kph takes FOREVER)! It made me think I was back on my 50cc! Rode it home for lunch (no highway, obviously) and back to work, no change. On the way home after work, it suddenly regained power . . . while in motion! Needless to say I couldn't troubleshoot it when it's working.

This week I noticed a slight power drop occasionally when leaving a stoplight, but just for a fraction of a second, then it would accelerate normally. Now it's back! I thought it might be a clogged muffler (that's kind of what it felt like when it "freed" itself up) so I took off the muffler and ran it with just the pipe . . . no change. I've also tried cleaning the air filter, checked for vacuum leaks (lines and intake), changed the gas tank vent line (read that somewhere), and checked the valve lashes . . . all checked out normal. A neighbor suggested maybe a burnt valve, but wouldn't that affect the performance consistently instead of being sporatic?

I'm going to check and clean the carb today (inspect the jets, slide, etc.), but would be open to any other suggestions!

[olivertwisted]

Sorry, you're having troubles @ jomama0687 . After all that you've checked already, I'd for sure be checking for fuel delivery problems too. I've had vehicles behave that way when a particle frees up from the tank and plays "peek-a-boo in the fuel line . I hope so, easy fixes are great.

[jomama0867]

UPDATE! I found the culprit . . . stuck slide in the carb! Learn from my *@#%in mistake . . . when searching for an intermittent problem, CHECK THE COMPONENT WITH MOVING PARTS FIRST (duh)!    

[olivertwisted]

Hooray!!!!