Alot of people have a hard time starting and running the Chinese atv's when new and also when cold. Most of these come with a gelpac in the carb floatbowl for shipping so it does not ruin the float durring shipping. It is supposed to dissolve when fuel mixes with it. Many make the mistake of driving the atv once started. This is a mistake. You must let it idle for at least 30min for the gel to dissolve. If you do not do this you will risk the chance of clogging the jets and the initial adjustments will not work and it will not run right untill all the gel is gone. Most of the time these will start with the movement of the choke then you can lightly feather the throttle to keep it running. If you can reach the idle screw you can turn it up till you dont have to feather the throttle. After about 30 min you can make the final adjustments. CHANGE THE OIL BEFORE YOU RIDE!!! These come with a cheap shipping oil and MUST be changed or engine damage WILL occure.

The idle screw on the right side of the carb is usually a phillips head screw on the carb with a spring around it. The air/fuel screw is the flathead screw usually on the left side of the idle screw. Here are some basic adjustments to get it started and to tune it once broke in.

The mixture screw had been set-up at the factory before shipment and should not have to be reset. If necessary, refer to the adjustment as below:

1. Make sure the air cleaner is clean.
2. make sure the choke lever is OFF while running once warm.
3. Warm the engine up for 3-5 minutes.
4. Turn the mixture screw clockwise until fully closed,
then turn the mixture screw 2 full turns out.
5. Adjust the idling screw until the engine idles EASILY.
6. Turn the mixture screw slightly clockwise and
counterclockwise until the highest engine REVs obtained.
7. Adjust the idling screw again until the engine idles
EASILY.
8. Repeat the step of 6 & 7 till getting the best
performance...
*ENGINE IDLES EASILY means:
The engine idling screw must be set correctly to get a
slowest engine idle(1500 rpm - 1600 rpm), but does not
cut out if you press the accelerator quickly.


Cold weather starting will need an additional adjustment to help aid the starting process.

Most of the manual choke carbs have an adjustable needle inside the carb. Lowering the clip (raising the needle) you will be able to open the throttle and get more fuel into the intake quicker. This helps in the cold weather because the colder the weather the leaner the mixture is. You want richer in the colder weather.

1- Unscrew and pull the top of the carb off with the cable and there will be a slide with the needle in the center.
2- Disconnect the cable through a small slot in the side of the slide.
3- Now you can take the needle out from the slide.
4- The needle will have a very small e clip in a slot on the needle. The needle will have 5 slots. Lowering the clip is richer the and raising the clip will lean it out.
5- Put the clip on the lowest setting for cold weather. DO NOT DROP THE CLIP! They are very small and hard to find.
6- Reverse the process with installing the needle back into the slide, installing the cable, slide the slide back into the carb and screw the cap tight.
7- Now make any adjustments as stated above in the carb tuning.

8- Once the weather warms up you may need to lower the needle for the hotter temps or it will run too rich.

These steps will work on 99% of these atv's. They are very hard to get running and people get upset when they turn the key and it does not run. Dont forget these are not set up at a dealer like the name brands so the most basic adjustments are done from the factory. These are built in china and the temps are hot so thats how the adjustments are done. As we all know in America the temps vary and these are not set at all for cold temps.

Hopefully this helps everyone with these concerns. These really do run good once tuned properly and with proper maintenance they will last a long time. And if you have any questions PM me and I will try to help as best as I can.

Good Luck!
2many

 

First, thanks for writing such a detailed and informative procedure for carb adjustment. When my atv arrived ( 50cc meerkat), the throttle cable adjsutment jut was loose. I set it by the procedure in the instruction manual ( about 4mm play). I still have a problem with the engine cutting out if I open the throttle quickly. If I open slowly, it is fine; problem is, it's hard to get a 6 yr old to understand that! I have tried the c-clip in various positions, each time adjusting the idle and mixture screws for a smooth idle from 1500 - 1600 rpm. Any ideas?

 

Did you drain the float bowl a few tomes. There is alot of junk floating around in these. I just bough a Meerkat also and it took a while for it to run right but it is net perfect. When I drained the bowl I noticed alot of metal shavings in the fuel. This may have clogged the jets. You need to let it run for a while to get the gel to dissolve. It takes longer on these little 50's than the bigger 90-110's. I may have to take the carb off and clean all the jets.

 

We've run at least 3 gal of gas through the atv with no improvement. I have had the carb apart twice, and didn't find anything in the jets. One more thing I found is that if I have the choke about 1/3 open, I can rapidly depress the throttle with no hesitation; of course with the choke on there is no power once it accelerates. I have tried the c-clip on each slot of the throttle needle, with the same results. Also, if my son holds the throttle wide open to try to start moving then suddenly releases it, the atv will usually cut off when returning to idle. Concerning the jets, I removed both brass inserts inside the carb and can see light through all small holes in them. Is there anything else in the carb I can check for blockage? Like you said earlier, with this BMX tranny it really flies once it is going; I am going to switch from a 37 rear sprocket to a 47 tooth to pick up the bottom end. Once that is changed, and I get the carb corrected, it should be a solid machine.

 

Going from a 37t to a 47t is a HUGE HUGE difference. You may not want to go that big because the engine may rev too high once going.

 

Since I am going to have to machine an adapter no matter what sprocket I buy, I'm not limited by tooth count. What would you suggest to improve bottom end? Maybe 40 or 41? Also, am I correct that the chain size is 428? I'm going to mic it tomorrow at work and compare to a chain size chart, since I can't find any markings on the chain. BTW, the atv seems pretty tough, considering what my son has been doing to it once it's moving!!!

 

I would say no more than 41-42t. How would you use a spacer for the sprocket. Wont that make the chain out of alignment with the front sprocket?

 

Since I haven't found a rear sprocket to match the bolt pattern of the splined axle adapter, I will either machine a stepped disc with bolt holes for the new sprocket on the outer rim and the existing axle adapter on the inner circle. The step will be equal to the thickness of the new sprocket, to maintain alignment with the front gear. Or, I might weld a disc inside the new sprocket with bold holes to match the existing axle adpater. Just depends on what will give the best fit. Matt at Wicked Rocket was going to try to order a larger sprocket at no charge, but I figure I can spend $15 - $20 to try it myself, in case he can't find one.

I've pulled the carb to soak in an ultrasonic cleaner at work tomorrow. While I'm at it I think I'm going to add an extension to the right side footrest, to give my son a place to rest his foot beside the brake pedal.

Have you ever heard of a company called AceDivision.com ? They list a new carb for these atv's for about $30.00. Seems too good to be true at that price. They also have what appears to be a complete engine / semi-auto tranny for $170.00 plus s+h. I might go for that if I can't get enough power with the sprocket change and carb work.

 

I've been trying to find a replacement rear sprocket for my kids 110 redcat and i am having no luck with matching the bolt patterns. Does anyone know of such a thing. don't really want to have to have something machined.

 

By chance, the sprocket I ordered from Dennis Kirk had the correct bolt pattern for the 50cc rear axle. It was a sunstrand sprocket for a kawasaki, not sure what model though. Someone at Dennis Kirk might be able to find a fit if you can call and give them the bolt spacing on your sprocket adapter.