need help figuring out whats wrong with my Lifan 200cc GY-5

[garyfisher]

I just bought a used 2007 American Lifan LF200GY-5 from a guy on this website. It had 800 miles on it. I rode it once 2 weeks ago. Then I rode it again today. I tried taking it on a 2 hour trip. I was riding in 5th gear at about 7000rpm for about a hour (65mpg) all of a sudden I hear the bike die.

What I mean when I said the bike died is that it stopped going. It seems like the bike ran out of gas but the bike has a full tank of gas. I pulled over and tried to start it. It wouldn't start. After a few minutes of sitting, I could start the bike with the choke on. I turned the choke off and could ride the bike again. yippie.

Then, it did it again. Seemed like it wasn't getting gas and just shut off. I pulled over and let it sit for a few minutes, then it started back up.

To make a long story short, this happened about 7 times. Each successive time, it would happen faster than the time before.

Finally, I couldn't get the bike to start at all and it got dark out. So I left the bike in a parking lot, where it sits now.


Once I get the bike started, it sounds like it's running great, until it dies.
What may be wrong with this bike?

[bechandler07]

i have a hi-bird 200 and mine has done that after alot of hard riding . to my understanding there is a rev limiter in the cdi ignition and that kills the motor if it revs too high . there could be a problem with the cdi box . i am thinking about putting a performance one on my bike without the limiter to see if that solves all my stalling issues

[forchetto]

Sounds a lot like fuel starvation caused by an air lock in the gas tank. What happens is that the breather that lets air into the tank to replace the gas that is being consumed, is somehow prevented from getting in. A vacuum is created and no gas can leave the tank until some air gets in.
The fuller the tank is, the quicker and more often this manifests itself, as there's less air above the fuel.

The symptoms are the same as running out of gas and one clue is wether you can hear a "hiss" of air rushing in when you open the gas cap as soon as it happens. With your helmet off of course, as it will be a very faint noise.

I don't know the breather arrangements your bike has. Some rely on a hole or channel in the gas cap, not immeaditely obvious but it's there, together with a ball valve that prevents gas escaping when you drop the bike. This ball can be heard rattling inside the cap if you hold it to your ear. If it has one and you don't hear it, it may be stuck in the closed position preventing air getting in.

Sometimes the airways can be blocked by dirt, fluff or even moulding flash left over from the manufacturing process. They're not easy to check, as they follow convoluted paths inside the various parts of the gas cap. In the old days the breather holes were visible from the top and bottom of the cap and you just poked a bit of wire to clear them. Not now of course.

Others, with more modern emissions specifications, have a sealed cap and a hose that goes to a sort of plastic canister full of charcoal that absorbs raw hydrocarbon fumes from the fuel evaporation. Not sure how this works. If so, check the hose to ensure it's not trapped or kinked in anyway.

This sort of system can be identified by the fact that there will be two hoses running down from the gas tank: One, the fuel hose, and a second one that is the breather hose. Check this one out carefully for kinks and being trapped by a clip or under some metalwork on the chasis, etc.

If you suspect those are the reasons, you can check this out by riding with your gas cap not fully closed and see if it happens then.

Another possibility is a gas vapour lock. This happens when a part of the fuel system, a fuel supply hose or even the carb itself gets very hot and some fuel vapourises creating a bubble of gas vapour in the pipe. No gas can get through. After allowing time to cool off, things return to normal. Check the routing of the fuel hose and ensure it doesn't have a huge loop downwards on it, get it going as directly into the carb as possible and away from hot parts like fins, etc.

Yet another is carburettor icing. Cold, damp weather together with the cooling effect of gas evaporating in the carb, actually creates ice inside the carb venturi that ends up choking the carb. Sometimes some frost is visible on the outside of the carb as well.
Once again, after a short interval the engine residual heat melts this ice and things return to normal. The perfect crime...like stabbing someone with an ice dagger, no-one will ever find the murder weapon.
If this is the problem there are additives to mix with the fuel, mainly alcohol based, that absorb the moisture that gets into the gas and is the main cause of the ice forming.

Other things to try out if all the above seems unlikely is checking to see what make of spark plug you have. If it's something obscure like "Torch" or some other strange make produced in a jungle clearing somewhere, replace it with an NGK Spark plug. Chinese plugs give trouble sooner or later.

[BUG]

Another thing to check- Some of the Chinese bikes fuel lines are much longer than needed, that compounded with heat and a soft thin fuel line cause them to kink.

[SeerAtlas]

I don't like the fact that it finally got to where you couldn't start it at all.
I'd turn OFF the petcock and check the float bowl of the carb. Could be you got some debris in there clogging up the works.
Hope its something simple.

Seer

[suprf1y]

Yet another is carburettor icing.

That was my first thought.
What was the weather like at the time?

[AZ200cc]

Loosen the gas cap and go for a ride...That's my guess

[garyfisher]

Hello all. I am back. I abandoned the bike at a gas station because it was getting dark and would no longer start.

I came back to the bike this morning and it started right up. I rode it home, no problems whatsoever.

I know it wasn't getting fuel.

Thanks for all of the advice.

[warrior91]

Classic Chinese gas cap/air lock syndrome.

[joebrads]

that was what mine was doing to the tee. i drained gas tank put fuel filter on and changed fuel lines to better ones. also cleaned carb or bowl. it was fixed thanks to all of you on here.