hard starting huasheng 49cc - Motorized Bicycle

familyguy · #1 03-24-2012, 04:08 PM

bout 500 miles on the motor, started to start sluggish (wont start with choke). like symptoms of a dirty carb, so cleaned the carb real good, did find some debree in carb, blew out orifices. put back together, same issue. i have to pull with choke on ( wont fire), flip choke off & pull start giving gas and it stumbles to a start, after it warms up, it runs/ idles great....SO... i put in a new plug, a new magneto, fresh gas, and even changed out the old carb with a brand new one, still wont start in choke. i have even tuned the old & new carb starting at 2 turns out on the air screw(brass) and gone up to 3 turns. normally between 2 and 3 turns out works great for me. i can start it through the method i told above. and can ride it all day once i get it going, it runs well.lots of power! could the valves be causing this? pretty much the only thing i havent done.
your input is greatly appreciated.
thanks

familyguy · #2 03-24-2012, 04:39 PM

it used to start first pull, or even half a pull sometimes

Fugi93 · #3 03-24-2012, 05:25 PM

Does it try to start on full choke on the first pull or two? I know my 49er doesn't like full choke in warm weather. It'll start but dies immediately before I can get the choke lever back off.

Bikeguy Joe · #4 03-24-2012, 05:32 PM

Could be an intake leak, or valve not seating fully (for several reasons).

familyguy · #5 03-24-2012, 05:39 PM

well the new carb came with new gaskets and its sealed tight so i think im gonna start lookin at the valves...to adjust valves, does the piston have to be in certain position?

familyguy · #6 03-24-2012, 06:02 PM

Quote:

Originally Posted by Fugi93

Does it try to start on full choke on the first pull or two? I know my 49er doesn't like full choke in warm weather. It'll start but dies immediately before I can get the choke lever back off.

no it doesnt even try to start, i could yank it 10 times and nothing, so i flip the choke back off, and it will try to start but will need throttle to resess-i-tate.

The_Aleman · #7 03-24-2012, 08:42 PM

Definitely do a valve adjustment. It'll help overall - starting, idling, cruising.
Before you adjust it properly, try to find out how far off they are already!

Oh, and don't worry about air leaks. They are extremely unlikely, considering the intake is a ~3/8" piece of plastic with a gasket on both sides.