yy50qy6 jonway gator bogging down at start off By dipdo (Read 1,448 times)

[dipdo]

Hi all.  My YY50QT6(Jonway Gator) bogs down at take off, no power then it picks up.  I have replaced the carburetor thinking that was the problem.  I buggered up the bolts on the old one trying to get it off.  I replaced my plug also, it was black with carbon(while replacing carburetor)  Even with the new carburetor its very boggy taking off.  I also replaced the fuel filter.  At stop lights i have held the brake and given a little gas, thing cuts off on me.  Restarts fine.  Starts fine normally.  I replaced the battery same time as carburetor because it was going bad.  Any ideas what I need to check?  Any help would be great.  Thanks all.

[JR]

Time to check the valves and see if they are off, classic symptom of tight valves. We have a how too in the tech section.


JR

[dipdo]

Cool.  Dont see the tech section, but found this video on Youtube:Valve Adjustment.  Seems simple enough, problem is where do I find the information on what to adjust them to?  .002, .003, .004 etc?

[dipdo]

I have done a google search to no avail on the adjustment for my scooter.

[JR]

Intake .003 and exhaust .004 can even add .001 to each if you like.

.thescooterprofessor.proboards.com/thread/321/valve-adjustment-troubleshooting" rel="nofollow" target="_blank">.thescooterprofessor.proboards.com/thread/321/valve-adjustment-troubleshooting

.thescooterprofessor.proboards.com/thread/99/daymark-gy-6-valve-adjustment" rel="nofollow" target="_blank">.thescooterprofessor.proboards.com/thread/99/daymark-gy-6-valve-adjustment




JR

[dipdo]

Awesome!! Thanks JR. I dont mean to question your knowledge, but where did you get the measurements?

[alleyoop]

A lot of experience with this motors, rule of thumb for the 50cc motors .003 inchs I usually recommend BOTH at .003 inchs and the 150s .004 inchs on both, the 250s .004 on the intake and .006 on the exhaust. What happens is depending on the quality of the head the valve seats compress with each explosion and closing of the valves. Due to the extreme heat on the EXHAUST valve that is usually the valve that after a time it will not seal and the motor looses compression.
The INTAKE VALVE not so much because it get nice cool air and cool fuel to help it keep the temp down. But the Exhaust valve gets really hot and when that happens the motors are hard to start and will not hold low idle. So after you start them and get the motor nice and hot and are riding around and you come to stops the motor wants to die or it will die if you do not keep giving it more gas to bring up the rpms.
If you let go of the throttle they usually will die.
Alleyoop

[dipdo]

Yeah that was happening to me back in December 2013. Took it to the shop and they adjusted the exhaust valve. They only let it cool about 30 min before adjusting. I was dumb at the time thought 30 min cool down was OK. So they didn't adjust properly. I am gonna try that in a day or 2. Again thanks for the information.

[dipdo]

I adjusted the valves this morning. In=.003, Ex=.004. Still no change in the take off.

I broke my belt a couple weeks ago had that replaced at a shop, they had to change my weights also(2 were in pieces). I know they put in 4 7g and I think 2 5g weights. I know it was 4 7's and 2 of something else. I just found out that is incorrect. I am going back up there in the morning to talk to them about it. Could this be my whole issue?

[alleyoop]

No those weights will not cause your bogging starting off.
Now that you re-adjusted your valves it is time to adjust the carbs fuel ratio mixture.
If it is bogging that means it is not getting enough fuel and just a lot of air.
Turn the FUEL RATIO MIXTURE screw on the carb COUNTER CLOCKWISE 1/2 turn and see if that eliminates the bog on take off.
Alleyoop

Here is what your carb probably looks like SEE THE FUEL RATIO SCREW turn it COUNTER CLOCKWISE 1/2 turn.

[dipdo]

I have adjusted that. I did what the guide said. While running, warmed up. Turn in till moped shuts off. Then turn out 1 and 1/4 turns. Then reset idle accordingly. It seems to have helped some. Sometimes i take off better others i have the snail effect. Haven't been able to mess with it for a couple of days. I will try the 1/2 turn clockwise in a day or 2. Thanks for your help and patience.

[alleyoop]

To adjust the carb correctly here is how to do it follow the procedure and take your time, OFF 1/4 in either direction makes a big difference. Once the carb is adjusted properly and it is still a problem then I would say the problem is in your CVT either the Variator Guides and or your weights and or belt. Also when the belt broke DID IT SHRED into pieces, if so did they clean out the clutch area specially by the CONTRA SPRING?
Alleyoop

thescooterprofessor.proboards.com/thread/3001/4-stroke-carb-tuning

[dipdo]

I adjusted the carb. there was no change, other than it getting to lean or rich. The belt did shred. They did clean it out. They took off the clutch and checked it for me. Two of the weights were destroyed so they replaced those. 4-7grams and 2-5gs(I believe 5gs...it was 2 of some weight). I realized recently there is a little black smoke that puffs out of the exhaust when i give it gas. It seems to run basically okay in the first mile or so, then goes down hill quickly. I am at a loss..

[alleyoop]

Black smoke your to rich you did not adjust the carb mixture correctly and it will run like a dog period.

[dipdo]

Okay. So I adjust the screw in(clockwise) 1/4(how about an 1/8)of a turn. How long should I give it to settle in? I am asking to be sure. Plus I don't have the guide with me as I type this.  One more thing.  How often are "new" carbs actually bad?


About the weights.  Is that ok the 4-7's and 2-5's? Or should it be all the same or 3of x and 3of y?