Adjusting the HuaSheng 142F (49cc) carburetor

[user51768]

I have had a few members pm me for help adjusting their HS carbs
this info was posted by Quenton (pres of EZM)
I am reposting because I couldn't remember where it was located

"Adjusting the HuaSheng 142F (49cc) carburetor

In order to adjust the carburetor it is necessary to warm the motor up first. The motor should have at least 5 minutes running time before any adjustments are made.

On the left side of the carburetor near the front is the idle mixture screw.

On the HuaSheng motor the idle mixture screw is a fuel adjustment, not an air adjustment.

Simply adjust the screw for maximum idle, and then turn the screw approx 1/16" counter-clockwise [slightly rich].

Check the throttle response, and adjust the mixture if there is a hesitation. Turn screw clockwise if it "bulks" and then catches on [rich], or adjust screw counter-clockwise if it accelerates and then drops off quickly [lean].

Have fun,
__________________
Quenton "Lee" Guenther
EZ Motorbike Company
www.ezmotorbike.com"

Replying all the way into 2018. Oh well this is a very informative thread, hopefully there are still people following and active on this. On my current motorized project bike I'm having a huge pain in the ass starting the motor up if even at all. I have to use starting fluid :/. From what your post was saying I could drill out a brass plug that is in place of the A/F mixture screw. If I adjust the screw would that put life in the motor?
I was also told that this motor might be running too lean thus it not starting up.
Here's a picture of my bike:

I have the HuaSheng 142F (49cc) motor. From recommendations from another forum I was told that there is a A/F adjustment screw hidden behind the brass plug on the other side of the carburetor. Pictured here:

(A/F adjustment screw behind the brass plug closest the the engine)

He stated "Lean engines burn cleaner, but too lean = no fire. I prefer slightly on the rich side, engine runs cooler."
He said if I took out the plug, I would be able to tune the motor.

Would this be the miracule cure to make the motor start?

 

[KCvale]

Glad you are fixed cliped.

 

[KCvale]

Ohh my...

The V-mount HS carbs unlike their rack mount brothers, have no fuel pump. If your tank is almost empty it doesn't have the weight to push all the fuel up to the carb from that huge fuel filter below the carb.

I suggest you loose that filter and use a smaller one, and keep all gas ABOVE the carb.

 

[CrazyDan]

I agree kcvale, way too much fuel line dipping below the carb.

 

[KCvale]

I agree kcvale, way too much fuel line dipping below the carb.

This is an easy fix, you just got to understand the problem ;-}

 

[artmaker]

This is a great thread. I'm having issues too and already see a few things I need to go try.
Was sitting on hold at gasbike.net when I found this. They never did pick up but I might not need to buy a whole new carb.
Mine (long story) wouldn't fire. I HAD it running, cleaned the carb when it wouldn't idol or would die coasting on down hills.
Just walked it across the street to my mechanic. They were able to get it started. They checked my plug, it's fine. (I need a socket that fits... on my to get list.) But it won't stay running.... so gotta be a fuel mix issue.

I did see the post above with the fuel line dipping below the carb. Mine is too. Easy fix there.... will do that first.

So what are everyones thoughts on getting a micro drill set and fitting a bit into the jet, then use the next size up and widening the thing?
Read that somewhere but I would think that's a last resort.

 

[KCvale]

So what are everyones thoughts on getting a micro drill set and fitting a bit into the jet, then use the next size up and widening the thing?
Read that somewhere but I would think that's a last resort.

What is your altitude?
When I was in Phoenix (1088 ft.) I never had to adjust the mix or dick with the jets.

We just bought a house and moved up to Camp Verde at (3153ft), with that 2K gain in altitude I expect my last 4-stoker will need some tuning if I sell it up here, but I think I'll have better luck down the hill in Phoenix, I always sell my 'no customer, wild hair' builds there ;-}

Hey Art, whats with the zip ties?
It looks to me like you are trying to hold your engine in with zip ties across your carb!?

 

[artmaker]

Hey Art, whats with the zip ties?
It looks to me like you are trying to hold your engine in with zip ties across your carb!?

I think you have me confused with someone else. I only use zip ties to hold cables in place, nothing more.
Here, my ride (photo taken before that horrible transmission was replaced. NEVER buy from thatsdax. Notice the clutch is exposed? yea bad idea. All replaced.

 

[curtisfox]

Where did you get them fenders? Got a link?..........Curt

 

[artmaker]

Where did you get them fenders? Got a link?..........Curt

Came with the bike. Actually when I first started thinking about a motorized bike and signed up for this and another forum, someone on there had this bike, almost brand new with a 2 stroke on it. not even broken in yet. Offered to sell it to me and I jumped at it. Now that bike originally had the coolest pinstripe design on the fenders, but the shipper DHL mangled the bike. And live and learn, I should have made the driver wait while I looked. But the seller felt so bad he contacted the place he bought the bike and sweet talked them into sending me a new set of fenders. (minus the stripe.)

If you google the bike, they still make these. It's called a Manhattan flyer 6 beach cruiser…. or here, easy enough to find it.
http://www.manhattancruisers.com/10_flyer6_m.htm

Note…. I had to have the tires replaced, and had the rear wheel respoked with thicker spokes. Rolling over a twig was enough to cause a flat. No more flats since I did that. Get good tires and the respoking job is well worth it.

 

[KCvale]

I think you have me confused with someone else.
I only use zip ties to hold cables in place, nothing more.

Sorry, I was referring to this bike a few posts up.

On my current motorized project bike I'm having a huge pain in the ass starting the motor up if even at all.
If I adjust the screw would that put life in the motor?
I was also told that this motor might be running too lean thus it not starting up.
Here's a picture of my bike:

Its hard to see the result of a project that may have been over the builders mechanical skill level.

 

[artmaker]

Sorry, I was referring to this bike a few posts up.

Its hard to see the result of a project that may have been over the builders mechanical skill level.

I figured you meant that one. NP.


I'm still trying to figure out my own carb issues. Ordered one from gasbike.net on May 31st, it's now June 4 and they still haven't even shipped it. They don't answer the phone, or chat. And I am pretty sure it's not even the right carb. Trying to contact them now to cancel the sale. Found the right one elsewhere.

Here, they have this listed as a 4 stroke, but it sure looks identical to every TWO stroke one I find. I'm going to bail on them. Another company with zero customer support.
https://www.gasbike.net/products/4-stroke-nt-carburetor

 

[Larry 4570]

Replying all the way into 2018. Oh well this is a very informative thread, hopefully there are still people following and active on this. On my current motorized project bike I'm having a huge pain in the ass starting the motor up if even at all. I have to use starting fluid :/. From what your post was saying I could drill out a brass plug that is in place of the A/F mixture screw. If I adjust the screw would that put life in the motor?
I was also told that this motor might be running too lean thus it not starting up.
Here's a picture of my bike: View attachment 97961

I have the HuaSheng 142F (49cc) motor. From recommendations from another forum I was told that there is a A/F adjustment screw hidden behind the brass plug on the other side of the carburetor. Pictured here: View attachment 97962
(A/F adjustment screw behind the brass plug closest the the engine)

He stated "Lean engines burn cleaner, but too lean = no fire. I prefer slightly on the rich side, engine runs cooler."
He said if I took out the plug, I would be able to tune the motor.

Would this be the miracule cure to make the motor start?

I have this problem with mine. When I start my bike it starts fine throttle response is to the touch of the throttle. When I start to take off the motor runs real rough and shake then smooths out. Any ideas?

 

[Venice Motor Bikes]

I have this problem with mine. When I start my bike it starts fine throttle response is to the touch of the throttle. When I start to take off the motor runs real rough and shake then smooths out. Any ideas?

It sounds like 'clutch chatter'.... Use the pedals to help the bike take off & build up some speed (so the clutch isn't doing all the work).

 

[Larry 4570]

It sounds like 'clutch chatter'.... Use the pedals to help the bike take off & build up some speed (so the clutch isn't doing all the work).

Is there anyway around it rather than pedaling. Would my belt be to tight?

 

[Venice Motor Bikes]

Is there anyway around it rather than pedaling. Would my belt be to tight?

Keep in mind that these are 'motorized bicycles' not motorcycles... You're supposed to pedal it to help the tiny engine get going, (just like a moped)

If you don't want to pedal at all?, I suggest you buy a motorcycle or scooter instead.

 

[newfie]

all you people on here are great appreciate you all and hope ur all doing well down there.
I have this on the go, 49cc huasheng 4 stroke, it's a marcargi bicycle .
question I'm getting at is , if I remove that plug and get at the air/fuel mix screw will this give me more top end/speed I only gets 40k almost 30mph which I think is slow for this motor, idk? I hear it should do around 35mph or more, it seems to bog down in top end ...is like she wants go more but not getting it, would this hidden screw help with this problem, I don't have any other issues other than too GD slow...lol
thanks everyone and greatly appreciate any info I can get.
oh one know of and where to get a muffler for these things other than these lawn mower type things they come with...lol
thanks again .

 

[artmaker]

I have had a few members pm me for help adjusting their HS carbs
this info was posted by Quenton (pres of EZM)
I am reposting because I couldn't remember where it was located

"Adjusting the HuaSheng 142F (49cc) carburetor

In order to adjust the carburetor it is necessary to warm the motor up first. The motor should have at least 5 minutes running time before any adjustments are made.

On the left side of the carburetor near the front is the idle mixture screw.

On the HuaSheng motor the idle mixture screw is a fuel adjustment, not an air adjustment.

Simply adjust the screw for maximum idle, and then turn the screw approx 1/16" counter-clockwise [slightly rich].

Check the throttle response, and adjust the mixture if there is a hesitation. Turn screw clockwise if it "bulks" and then catches on [rich], or adjust screw counter-clockwise if it accelerates and then drops off quickly [lean].

Have fun,
__________________
Quenton "Lee" Guenther
EZ Motorbike Company
www.ezmotorbike.com"

Gotta be warm huh? I haven't been able to get mine STARTED in a few years now. Just built another bike with a two stroke. Thinking of taking off this so called UPgrade to a four, tossing it in a landfill, and buying another two stroke. Had nothing but bad experiences with this lousy four stroke. Never had near the headache with the two.

 

[curtisfox]

Here it is, https://motorbicycling.com/threads/adjusting-the-huasheng-142f-49cc-carburetor.41561/ ...........Curt

 

[Choochoo_nesby]

all you people on here are great appreciate you all and hope ur all doing well down there.
I have this on the go, 49cc huasheng 4 stroke, it's a marcargi bicycle .
question I'm getting at is , if I remove that plug and get at the air/fuel mix screw will this give me more top end/speed I only gets 40k almost 30mph which I think is slow for this motor, idk? I hear it should do around 35mph or more, it seems to bog down in top end ...is like she wants go more but not getting it, would this hidden screw help with this problem, I don't have any other issues other than too GD slow...lol
thanks everyone and greatly appreciate any info I can get.
oh one know of and where to get a muffler for these things other than these lawn mower type things they come with...lol
thanks again .

As I have done that recently, the easy answer is yes, adjust that screw will make a HUGE difference. I had the same issue, I could feel that the engine wanted to go more, adjusted that and instant improvement. As for the top speed, that will depend on the gearing you are using, easiest to change would be the rear sprocket. Finally, my engine kit came with the "basic" muffler, this one: https://www.gasbike.net/collections/mufflers/products/chrome-exhaust-muffler-1 , not sure how much it would affect performance.