Hey everyone, I just recently bought two quads as a bundle, they are both red cats one is a 110cc and the other a 200cc. I got the 110cc running perfect and I have no issues with that one. But the 200cc doesn't like to crank under load. What I mean by that is when the spark plug is installed the motor will turn over like once and then act like the battery doesn't have enough voltage to keep it going. But when I remove the spark plug the motor turns over with no problem. Its not a voltage issue, I just reclearenced the valves and they are in spec, the exhaust isn't plugged. Im lost and unsure what to do or check at this point. If anyone has suggestions or has experienced this problem please let me know.

 

Alex71 has just had the same problem. Turned out to be the trigger coil wired backwards. However, have a read through this Coolster 125 slow cranking as if too much compression before doing anything.
Link doesn't seem to work so, Coolster thread is in the kids quads section of the forum.

 

Hey merryman, I read through his post, and he mentioned that the bike would turn over normally when the lead was off his spark plug. The issue with that is whether I have the lead on or off the plug, it doesn't turn over correctly. So I want to say it has to be a timing issue rather than an electrical one, but from what I have read online, you can't adjust the timing on these 200cc pushrod motors. I may be wrong I'm not sure, this is the first time I'm working with a 200cc so I don't know much about them.

Also I tried what Alex71 said fixed his problem, switching two wires on the stator, unfortunately it didn't make any difference.

This was taken after I switched the blue and green wire back to where they originally were.

 

Also Ive never got this bike to run. It seems like a lot of the people experiencing the same issue can get their atvs running regardless of how badly it turns over. I've got it to start for maybe a second at a time but I have never seen it run for longer than that.

 

Switch those wires back, if it doesn't alter the slow cranking when you take the plug lead off it isn't an ignition timing issue. A flat or poor battery will cause slow cranking, as will bad connections on any of the thick wires, including earths. The Chinese makers have a tendency to make these leads too thin, so extra earths and thicker wires to solenoid and starter can help. For a bike to run you need a spark and fuel, check for a good spark, though as you say it sometimes fires, you are probably getting one. That leaves fuel. Clean the carb out, float bowl off, remove jets and blow through them and the holes they came from out with compressed air, check for water in the float bowl and clean it out. If there is a lot of water or dirt in the bowl, clean the tank out too.

 

I'll try replacing the possible "bad connections". I've previously worked on many bikes I understand what the engine needs in order to run. I have a great spark, brand new carb with a clean fresh tank, and fresh gas. I know it isn't a bad battery because I've used multiple that are known as good batteries and I've hooked it up to a jump pack to see if that would help (it didn't). But like I said I'll try adding some thicker wires to see if that helps.

 

Most likely cause is worn out crank bearings.