Lifan 140 Wont start? Very very strange...

[unit_mx]

Ay , posting this for a mate who recently bought a dhz monster 140cc. The bike has always been a bitch to start , had the valve clearences all checked by the shop etc. But now it wont even run. So basically I sorted this from a msn conversation:

Sickness:
- 'Bitch' to start , but always has been
- " doesn't sound like its firing on all cylinders but there's only 1"
- Once started it just runs rough like its cold but alot worse
- You rev it and it just dies and loses revs , then cuts out

What it has:
- Plenty of compression
- Plenty of spark
- It does start but doesnt run.

Whats been checked:
- Valves have been checked twice since new , bike has done about 8 hours riding. Valves checked when this problem occured by a proper motorcycle mechanic
- New spark plug
- Changed and checked CDI/REV BOX( so its not fried)
- Changed stator ( Old one had rust)
- Carby cleaned out ( was spotless)
- Fresh fuel , flushed tank
- Filter is clean
- Fresh oil

Sounds strange , I have checked many threads but no avail. All listed work was done with a motorcycle mechanic but he couldn't work it out.

So calling on all the tech heads or guys with experience on lifan as to what is occuring.

Also set up:
- 2008 DHZ Monster 140cc
- So guessing it has a 28mm Molket - a copy of a kehin PD28? Still on Standard jetting...
- Altitude - sea level
- Riding style: Playriding


Cheers

 

[coolmodee01]

uuuummmmmmmm,

maybe timing could have jumped a tooth but it's a long shot
could be a bent valve making it stick open
after that maybe coil and lead you might not be getting the best conection there somewhere

could also be carby problem still maybe a leak or air fuel or somthing

have fun with that

 

[unit_mx]

Yeh Thanks for the input Coolio , He has checked the timing too. Sounds like the shitty Molket carb , I cant see it really being an electrical problem. But at this stage anything could be the issue....

 

[coolmodee01]

yeah the mulket 28 are useless

my mate has had the same issue with this carby

he should maybe chuck somthin else on and see if it still play's up

 

[themountain]

Did you checked for airleeks on the intake??...but its probably the shitty carb....28 is anyway too big for that thing!!

 

[Dreadful]

Yeah I agree ....the runnin n dying thing sounds like carby for sure ...personally I'd take a punt and replace that before anything else.

 

[Sidney]

Sounds like you need some miracle juice.

 

[Custom]

Thats no help...Its out of stock

 

[unit_mx]

Haha classic Sid

I reccomended replacing the carb to him , but he couldnt justify buying a new one when his bike is new haha. Tried to explain how shit molkets are. Should go down to a vm26 of dhz im thinking.
I thought it would of been the carb due to the spluttering and coughing.

 

[sc140]

i had the same problem on the same sort of bike (DHZ 140cc) choke on the carby 30mm carby was stuff and also the grounding for the CDI was shot, good as new after replace 30 wit 26 and new wires for grounding.
could be the same for you.