Lifan 110 running problems

[spat12]

New to the forum, been tinkering with minis for a while now. But this one has me confused. What I have is a Lifan 110cc 4-stoke with auto clutch mounted in a mini baja trail bike...I can get it started usually but it takes a while for it to kick over. Once I get it started I can rev it up only a little bit and only if I gently ease the throttle up. The second I wack the throttle to accelerate hard it boggs down (like it loses all fuel/ spark) and damn near stalls if I dont let off.

The jets have been cleaned pretty good and my fuel system is well vented...is there a chance it could be my cam timing? Or should I be looking elsewhere to solve this problem? Thanks in advance!

-SPAT-

 

[bulldog93]

This sounds like a carbi issuie, try cleaning out your carbi, then do your jetting at the same time. To set the timming the will be marked a 'T' on your flywheel and a mark on the engine it should line up at 12 o'clock, to do the cam sprocket take the cover by the middle bolt on the other side, after you do that the will be a mark on the cam sprocket (think its an arrow and a dot underneath it) that should be lined up at 9 o'clock with the mark on the head, should be doing all this with the timing chain off.

 

[no_crf50_here]

Does it act the same way once it's warm, If so I'd be looking at first doing some cheaper options.

1. Clean carbie (you've done this)
2. Change spark plug
3. Change out all the fuel
4. New coil & lead

then report back

 

[spat12]

You guys are quick!
I also forgot to mention;
Coil and plug are brand new (did it with the old ones too)

I guess Ill pull apart the carb one more time and clean it really good this time...if it still gives me fits Ill check the timing.

Thanks for the fast responses!

-SPAT-

 

[DvDRip]

Sounds to me like you need to adjust your valve clearance, then if that doesn't help check to make sure your exhaust gasket is ok and manifold is tight.

THEN you can start playing with your carby

 

[thump*140]

more than likely you also have a Fakuni carby.
These have a tendency to just up and die for no apparent reason.
If you do all the above, and still have no joy getting it to run right, try playing with the needle jet, and if that still doesnt work, pull carby off, immerse in petrol, stand back, throw match at carby. Go on ebay, and buy a new carby.
Whooska. problem solved.

 

[spat12]

ok...I cleaned the crap out of the carb, put fresh fuel in, checked for the proper gap on the plug...and yet it still boggs down when I hold it wide open...its no good because I have yet to see the full potential of the setup I have as I can only motor around at quarter throttle....

 

[thump*140]

try raising the needle jet... to do this, pull the top of the carby off, pull the slide out, remove the spring and throttle cable, and inside the slide, you will find a brass needle..which has a little clip on it, in a groove near the top of the needle...
pull the clip off, and move it DOWN a couple of grooves... reassemble, and see how that goes..

(sorry not sure how mechanically minded you are... If you know how to do the above, try raising the needle jet... if still not good, have a look at the float level.)

 

[headsmess]

i smell valves being the issue... mainly cus of the hard starting...

and even, possibly, (except you dont mention anything about backfiring) the "anti-kickback" mechanism having its lunch.... they hold the exhaust valve open slightly and can cause major headaches....

check the valve clearance, then report back

 

[spat12]

ok...valve clearance is perfect

but here is an update-
I noticed the throttle problem gets worse as I ride it around and it gets hotter, almost to the point where I can no longer give it enough throttle to get it moving without being in 1st gear

also...I will be getting a brand new carb next week for next to nothing, so I will update after I install it and give it a run