Well, I'm back again looking for help. After lots of good advice from you guys I finally got it running a little over a week ago. I gave it about a half hour of heat cycles to break it in and after that started taking it up and down the street and running it through the gears. Finally this past Wednesday I decided it was time to let it rip. I took it out on the pond for some ice racing and opened it up. Of course it absolutely ripped...at first. After a couple laps it started to sputter on the top end, so I changed the plug. It didn't seem to help, I took a few more laps and it kept sputtering on the top end, and it finally died and lost compression. I knew I didn't melt the rings the plugs showed it running plenty rich. I pulled it over a couple times and I could here compression coming back through the carb. I took the top valve cover off tonight and this is what I seen. The valve on the left is stuck open, when the rocker arm makes contact it only pushes the valve down about 1/8" and it stays open until the piston comes to TDC and pushes the valve back that 1/8". The one on the right functions perfectly.

- what would cause the valve to stick? I only have about one hour on the new motor.

- Can I take the valve apart without removing the head? and do I need a manual.

- Heres my info
-107cc Lifan 3 valve
-DrAtv 22mm carb
-crf50 chinese pitbike exhaust

Thanks again for all your advice!

one more

springs, seals, dirt etc in the guides?

take them out clean the head real well and see if it fixes it.

you may have sizing problems, if they are aftermarket valves/head

i had an 80 do the same thing but i cleaned it and it works great

Might of bent the valve.

Correct me if I'm wrong but I don't think I could bend the valve unless the timing chain jumped off track, and the timing is perfect.

Oh mannnn! At this point you need to pull the head and get the valve out of the head and check if it is bent, the guide may need to be reamed also.

Could something be stuck in the valve holding it open?

My 110 heads don't look like that. Did you modify your head or run an aftermarket one?

That is the head that came on the motor, and I never touched it. I have looked at hundreds of pictures of Lifan motors, on this forum and others, and I have only seen one other 3V motor. It's in "spontanious combustion" I cant remember the forum members name, he also has a "tonka trike".

Contact Larry at Hooper Imports and ask him he knows the Lifans really well.

Heres a link to Flying W's "spontanious combustion" build. http://www.glamisdunes.com/invision/index....=131567&hl= This is the only other three valve motor I have ever seen, and its not even that similar. I will send Larry an email and some pics and see what he has to say. I'm suprised that I ended up with such an odball motor......these lifans seem to be a dime a dozen, and all the same. Only my luck I guess.

Update: I called Larry Hooper today and he doesn't sell these motors because they aren't legal to be raced anywhere in the U.S. But he said he has heard they are great motors and very fast. He also said he's not a mechanic, and theres no point usually because the motors are so cheap typically poeple just throw them away and buy another. I'm going to take it apart tonight and see what it looks like, hopefully theres no damage.

- is there any possible way that the head is supposed to have a bypass oil line going to it to oil the head?

- how are the valves supposed to be oiled? splash from the cam, etc?

Well I took it apart yesterday........And heres what I found. I am running a 22mm carb from DrAtv, the carb is brand new and only has one hour of time on it. I took the head off the cylinder and found one of the screws that holds the butterfly onto the carb STUCK inbetween the valve and the valve seat. It was the absolute last thing I expected to see, I was half pissed the screw was loose and half releived. There was zero damage, not one ding or dimple in the head or top of the piston. The valve was fine too, as well as the the valve seat, even the screw was untouched. I compressed the spring, grabbed the screw, took off the carb and put it back on the butterfly (with locktite of course). The valve dropped back down, and everything seems perfect, I reassembled it and I'm going to start it in the morning. I guess moral of the story is if you buy a cheap POS chinese carb don't assume they tightened all the screws. Luck must be on my side, I cant beleive there's not any damage.

First pic shows the screw inbetween the valve and the seat