49cc 4 stroke hua sheng trouble

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knarrgrant

New Member
I'm having a lot of trouble getting my engine started and keeping it running. It dies constantly and then won't start again. Any help?
 
That's not much to go on.

Start by thoroughly inspecting the fuel system; tank, filter, drain-cock, lines, carb. Ensure that your fuel is clean and fresh. A particle smaller that a grain of the pepper we put on our food will prevent proper operation. Be sure that your carb is adjusted properly.
If that's not it, move on to air and spark.



also- you haven't forgotten to turn off your choke have you? It does happen...
 
I don't have nearly as much experience as these two builders. I'm still trying to cast a wide net.
Yes. It is the carb.

Any progress knarrgrant?
 
Also I would say that it could be a possibility of a kink in the fuel line. After it sits for a little it may have enough fuel, but after it has used that fuel it has nothing to go on.
 
YesImLDS said:
Also I would say that it could be a possibility of a kink in the fuel line. After it sits for a little it may have enough fuel, but after it has used that fuel it has nothing to go on.
Click to expand...

Visually inspect the fuel line for kinks.........but it's still the carb ;)
 
I got a new issue now. When I try to start it, it makes a weird noise. Like a high pitched reeeerrrrrrrr. It's mechanical. I took the cover off and spinning the thing by hand which the rope spins it makes the same noise. I got about 250 miles out of it, never heard it before. Went riding around yesterday, came home shut it off and about an hour later it wouldn't start and was making that noise
 
I have a 4 stroke kit & I got so I could disassemble & reassemble the stock Ruixing carburetor with my eyes closed. Part of this was my fault for not having a fuel filter, which is dumb, but this carb is still an awful design, and it was hard to work on tucked between the engine & frame. When that carb got stuck open it would leak fuel all over through it's overflow tube.
On this site I read about another member that mounted an angled manifold & NT carburetor on his 4 stroke. I went ahead and tried that and the difference is astounding. For the first time since I installed the kit I am actually riding the bike farther than a block, and working on stuff besides the carb.
Anyone curious, the manifold is a member on here called FFV8, and I got the carb from Kings, although they almost seem to grow on trees.
 

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Panhead said:
...Part of this was my fault for not having a fuel filter, which is dumb, but this carb is still an awful design, and it was hard to work on tucked between the engine & frame.
Click to expand...

They don't well in most bikes without doing something like cutting off the choke lever, but overall pretty good carbs I think.

On this site I read about another member that mounted an angled manifold & NT carburetor on his 4 stroke.
Click to expand...

Ya, nothing to it.

2_SlugoDoneRight-Covers-1280.jpg


The NT is not quite as good as the HS but it's simple and it works.
 
Your fuel mixture screw might have been be set to lean at the factory mine was and it took many pulls to get it started and it always died on me when coasting. You might have a brass plug covering the mixture screw if so it's easy to drill it out with a left hand bit.

My was set from the factor about 1 and 1/4 turns out. The base setting to start tuning is 1 and 1/2 turns out. After many rides and fuel adjustment settings I'm just under 2 turns out and it always starts on the second pull and is running great now.
 
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I used to have one of those engines and never liked that carb. It wasn't until I was running a 99cc predator that I read about changing over to the NT carb, made the change and it made a big difference in how well the engine ran, throttle response. This was on a Predator and not the HS, but I think you can expect the same results. If all else fails in the good suggestions you have gotten from members, change to the motorcycle type of carb (NT) and be done with it. And I always install a fuel filter into the gas line first thing on a motorbike.
SB
 
Ok , this is just a stab in the dark. Did you ever put real oil in the crankcase when you got your engine? or did you leave that tiny amount of factory build oil in it? perhaps the noise you hear is the connecting rod/crankshaft friction.

If you have the 7G kit, the clutch bushing - oillite- or whatever they call it may need to be oiled or soaked in oil, then put back in place?

Both scenarios can cause the wild screeching you stated.
 
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