Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 12, 2013 21:26:43 GMT -6
Story behind the scooter:
i recently purchased a 2009 velocity 150cc gy6 scooter for 300$!...yes 300$!..the scooter is in pretty great condition for 4000 miles. I found it in my neighborhood..a middle-aged woman bought it for her nephew, he rode it, parked it a few months ago since he shipped off to navy.
Now then, upon pushing the scooter to my home (two streets away, battery was dead), i charged the battery, put it on the center stand and cranked the starter button. Behold, it started right up. After letting it run for a few minutes, I decided Id see what the scooter was made of, as Ive had 2 of these style 150cc gy6 scooters. Now the scooter has good throttle response and pulls hard at wide open throttle until about 30-40mph at which time it bogs and jerks around until i pull back on the throttle and it smoothes out. The scooter acts as if it has a speed governor. My initial thought was a valve adjustment, upon completing that task, the results were the same with a little better throttle response. My 2nd thought was a vaccuum leak, so i replaced all the lines with new hoses EXCEPT the bigger hoses for the PAIR canisters. (havent got to that yet). Upon completing all the fuel/vaccuum hoses and a new filter, same result, still bogging around 6k rpms. I then decided to pull the fuel bowl off of the carburetor and inspect/ clean. Everything was fine (float/ jets cleaned) Once again, no results. I also replaced the cdi with a brand new stock one.
Im at a loss, i know this scooter has good power and can be fast i just cant figure out what is making it bog out and making me drive around town at this annoying slow speed. i also pulled the fuse for the alarm on the off chance that that had something to do with the problem, nothing.
I know this is long to read but I wanted to give as much info as possible for help.
Any and all help is appreciated. Thanks
|
|
|
|
Post by Alleyoop on Aug 12, 2013 21:29:51 GMT -6
|
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 12, 2013 22:03:26 GMT -6
Thanks for the reply, Its been years since Ive been on this forum, when i was active on this site back then you sir helped on more than 1 occasion, thanks again I will try the procedure in the morning. |
|
|
|
Post by Alleyoop on Aug 12, 2013 22:10:04 GMT -6
Good luck, but how you describe the problem it is just a fuel delivery problem.
And you can find out which is causing it RICH OR LEAN.
Ride it and bring it up to where it starts to act up. Then back off the throttle about 1/4 of an inch and hold it there.
A. If the scoot speeds up it is running LEAN and needs a little more fuel.
B. If the scoot just settles down it is running RICH and needs a little less fuel.
That way you know which way to turn the Fuel Ratio Mixture screw right off the bat.
Alleyoop
|
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 12, 2013 22:40:37 GMT -6
Good luck, but how you describe the problem it is just a fuel delivery problem. And you can find out which is causing it RICH OR LEAN. Ride it and bring it up to where it starts to act up. Then back off the throttle about 1/4 of an inch and hold it there. A. If the scoot speeds up it is running LEAN and needs a little more fuel. B. If the scoot just settles down it is running RICH and needs a little less fuel. That way you know which way to turn the Fuel Ratio Mixture screw right off the bat. Alleyoop it speeds up when i back off the throttle a bit. This is all starting to make sense. Maybe a week ago, i put the scoot on the center stand and attempted to fool with the air fuel screw, however i wasnt knowledgable of doing a quarter turn and letting the engine catch up. i only turned one direction and that was clockwise and it was also while i was holding the throttle around the area where it bogs out. It did not change performance much at all upon turning clockwise. As a side note, when the scooter is under no load on the center stand and held at wot, it acts as if the rev limiter is set at 6.5k rpms bouncing at that rpm steadily. |
|
|
|
Post by Alleyoop on Aug 12, 2013 22:43:14 GMT -6
So It is running LEAN that is why the rpms bounce.
Alleyoopl
|
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 12, 2013 22:56:28 GMT -6
So It is running LEAN that is why the rpms bounce. Alleyoopl Come to think of it, when I replaced the spark plug in the middle of all this, the old plug was quite white ish, shouldve been a dead giveaway, thats when i started my whole vaccuum leak/too much air deal. Its 12:53 am and my curiosity of this being the cure is almost to the point of going into the garage. |
|
|
|
Post by Alleyoop on Aug 12, 2013 22:58:18 GMT -6
HAHAHA, It is 11:57 not quite midnight here yet.
Alleyoop
|
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 13, 2013 22:15:49 GMT -6
HAHAHA, It is 11:57 not quite midnight here yet. Alleyoop Is my fuel filter supposed to be full? Its maybe 40% full at all times and located AFTER my petcock (gravity fed). Found a scooter parts store literally 1 mile away from my home! so I will replace petcock for 12$. Just wondering if my petcock isnt giving the carb enough fuel. Thanks |
|
|
|
Post by Alleyoop on Aug 13, 2013 22:36:25 GMT -6
You can test the petcock by taking the Fuel Hose off the carb and putting it in a container then take the Vacuum hose going to the petcock and sucking on it and fuel should come out in a nice flow and stop when no suction is applied. If it dribbles out then there is a problem. If your fuel filter is to big it will not fill. I only use VISU fuel filters they trap everything and can also be cleaned and reused. Also For Gravity Fed Systems make sure the FUEL HOSE, Petcock and Fuel Filter are going DOWNHILL from the tank to the Carbs Fuel Inlet NO UPS AND DOWNS. Alleyoop  |
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 14, 2013 9:30:54 GMT -6
You can test the petcock by taking the Fuel Hose off the carb and putting it in a container then take the Vacuum hose going to the petcock and sucking on it and fuel should come out in a nice flow and stop when no suction is applied. If it dribbles out then there is a problem. If your fuel filter is to big it will not fill. I only use VISU fuel filters they trap everything and can also be cleaned and reused. Also For Gravity Fed Systems make sure the FUEL HOSE, Petcock and Fuel Filter are going DOWNHILL from the tank to the Carbs Fuel Inlet NO UPS AND DOWNS. Alleyoop So im an Idiot, theres a nipple on the air/fuel mixture screw side of the carb, there was no hose on it! Put my finger over it and euraka, revved all the way to redline, what does this hose connect to? |
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 14, 2013 9:58:36 GMT -6
You can test the petcock by taking the Fuel Hose off the carb and putting it in a container then take the Vacuum hose going to the petcock and sucking on it and fuel should come out in a nice flow and stop when no suction is applied. If it dribbles out then there is a problem. If your fuel filter is to big it will not fill. I only use VISU fuel filters they trap everything and can also be cleaned and reused. Also For Gravity Fed Systems make sure the FUEL HOSE, Petcock and Fuel Filter are going DOWNHILL from the tank to the Carbs Fuel Inlet NO UPS AND DOWNS. Alleyoop Research tells me that this is the carb vent, how come when i put my finger over it, the scooter acts as if its fine? I ran a hose to it and plugged it and it wont stay running, im confused. |
|
|
|
Post by Alleyoop on Aug 14, 2013 11:27:08 GMT -6
The thing your talking about is the VENT hose and overflow for the CARB BOWL. You do not plug that up.
That is just like your gas tank Vent hole or hose if it is plugged up it will stop the flow of gas going out to your carb.
Alleyoop
|
|
Clinician
Currently Offline
Posts: 39
Likes: 0
Joined: Apr 1, 2011 21:12:27 GMT -6
|
Post by gy6ownsall on Aug 14, 2013 11:41:57 GMT -6
The thing your talking about is the VENT hose and overflow for the CARB BOWL. You do not plug that up. That is just like your gas tank Vent hole or hose if it is plugged up it will stop the flow of gas going out to your carb. Alleyoop I must be missing smething because when i plug it with my finger itll run all the way to redline and further. |
|
|
|
Post by Alleyoop on Aug 14, 2013 12:54:16 GMT -6
Is it the one shown here that says VENT LINE near the top of the carb? Alleyoop  |
|
..BAD TO THE BONE..