I bought a new 2006 Chinese 150cc scooter ( yes it new ). It starts fine and seems to idle OK by it takes about 12-15 minutes to warm up so that you can ride it. It will stall around 3000rpm if it's not warmed up enough. It has a auto choke and not sure why it takes so long. All my other small outdoor engines, i start and go! Any idea's?
New ( 2006 ) scooter warm up time issue?
- Thread starter mez
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Shouldnt be my friend take er back. Would have bought domestic or Japanese myself but still, go back and complain. Nothing should run like that brand new. Don't mean to insult you with that comment, wish you luck with it.
That's a great engine. Fan cooled, CVT gas-n-go trans, etc. It's a Honda GY6 "clone". You've most likely got a carb issue, either with adjustment or debris in there somewhere. Worst case, a new replacement carb is around $30. FWIW, I've got a Chinese 110cc ATV for my kids. Have had it since last winter. Not a single problem with it and it was just over $600 shipped to the door. FWIW, this exact 150cc is used on lots of Chinese ATVs and the engines themselves are pretty much indestructible.
Joel
Joel
Sounds like the auto choke isn't disengaging and might be causing the engine to bog down.
I'm not familiar with the type of choke on your machine but the ones on my ATVs are electric. It would appear that yours might be thermostatically controlled and functions by reacting to engine heat. It might be a bi-metal control that disengages the choke and it's not responding to engine temps as it should. I'd pull the carb and take a good look at the choke to see how it works and go from there.
I'm not familiar with the type of choke on your machine but the ones on my ATVs are electric. It would appear that yours might be thermostatically controlled and functions by reacting to engine heat. It might be a bi-metal control that disengages the choke and it's not responding to engine temps as it should. I'd pull the carb and take a good look at the choke to see how it works and go from there.
Originally Posted By: JTK
FWIW, this exact 150cc is used on lots of Chinese ATVs and the engines themselves are pretty much indestructible.
Joel
Yeah, there's a lot of them around here too - on scooters and atvs. Those engines actually are pretty good. The only problems i've commonly seen related to them are carb or electronic related. As long as you don't bypass or replace the rev-limiter (over-revving) they are hard to kill.
I'd start with replacing the electronic choke. If that doesn't do it then it's the carb. Replace the fuel filter as well, the stock chinese filters are junk and can actually come apart and block fuel-flow too. Don't forget an NGK plug as well, those factory plugs are notorious for the tips breaking off - falling down into the combustion chamber (not a good thing).
FWIW, this exact 150cc is used on lots of Chinese ATVs and the engines themselves are pretty much indestructible.
Joel
Yeah, there's a lot of them around here too - on scooters and atvs. Those engines actually are pretty good. The only problems i've commonly seen related to them are carb or electronic related. As long as you don't bypass or replace the rev-limiter (over-revving) they are hard to kill.
I'd start with replacing the electronic choke. If that doesn't do it then it's the carb. Replace the fuel filter as well, the stock chinese filters are junk and can actually come apart and block fuel-flow too. Don't forget an NGK plug as well, those factory plugs are notorious for the tips breaking off - falling down into the combustion chamber (not a good thing).
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This is what i gather on the web.
These models use an electric "choke". It's not a standard choke, in the sense that it doesn't choke off the flow of air (and make the fuel/air ratio richer). It is a device that shuts off the flow of air to the starting circuit as the scooter warms up. The bystarter is a small, black cylindrical device with two wires coming out of it. When the engine is running, 12V are applied to these wires. Over about 10 minutes or so, the bystarter warms up as the engine warms up. There is some wax in the bystarter (believe it or not) that is heated by a small heater. It expands, and extends the bystarter needle about 1/8". This is enough to close off the starting circuit.
After a number of years, the device builds up electrical resistance and it doesn't do its job any more. A new bystarter has a resistance of about 4 ohms. When resistance builds to over 10 ohms, it should be replaced.
To check for proper bystarter function, there is a complex test in the service manual that can be performed, but there is a simple test that works almost as well. Remove the bystarter and examine it. Are the wires in good shape? Is the needle in good shape? Nothing looks broken? Hook up a 12V source to the two wires. After about 10 minutes, the bystarter should become warm, and extend the needle 1/8" or so. Measure it with a pair of vernier calipers or whatever you have handy. If it extends properly it's probably ok. The only sure way to tell if it is bad is to do the full test as described in the service manual. This involves removing the carb and leaving the bystarter attached. Draw a vacuum in the starting circuit outlet. There should be little resistance when the bystarer is cold and plenty of resistance when the bystarter has been heated up. A bad bystarter will either not expand properly or not contract properly.
These models use an electric "choke". It's not a standard choke, in the sense that it doesn't choke off the flow of air (and make the fuel/air ratio richer). It is a device that shuts off the flow of air to the starting circuit as the scooter warms up. The bystarter is a small, black cylindrical device with two wires coming out of it. When the engine is running, 12V are applied to these wires. Over about 10 minutes or so, the bystarter warms up as the engine warms up. There is some wax in the bystarter (believe it or not) that is heated by a small heater. It expands, and extends the bystarter needle about 1/8". This is enough to close off the starting circuit.
After a number of years, the device builds up electrical resistance and it doesn't do its job any more. A new bystarter has a resistance of about 4 ohms. When resistance builds to over 10 ohms, it should be replaced.
To check for proper bystarter function, there is a complex test in the service manual that can be performed, but there is a simple test that works almost as well. Remove the bystarter and examine it. Are the wires in good shape? Is the needle in good shape? Nothing looks broken? Hook up a 12V source to the two wires. After about 10 minutes, the bystarter should become warm, and extend the needle 1/8" or so. Measure it with a pair of vernier calipers or whatever you have handy. If it extends properly it's probably ok. The only sure way to tell if it is bad is to do the full test as described in the service manual. This involves removing the carb and leaving the bystarter attached. Draw a vacuum in the starting circuit outlet. There should be little resistance when the bystarer is cold and plenty of resistance when the bystarter has been heated up. A bad bystarter will either not expand properly or not contract properly.
You can thank the EPA for problems like this. I bought my son a new Honda Recon atv last Christmas and it was slow to warm up and idle on it's own.
You would have to "baby" the choke in and out to keep it running until it warmed up some....some 5 minutes or so.
I pulled the carb, removed that stupid "D" head idle mix screw and took my Dremel and put a slot in the head. It now starts easily and idles better after adjusting that screw and enriching the fuel mixture.
You would have to "baby" the choke in and out to keep it running until it warmed up some....some 5 minutes or so.
I pulled the carb, removed that stupid "D" head idle mix screw and took my Dremel and put a slot in the head. It now starts easily and idles better after adjusting that screw and enriching the fuel mixture.
You can almost bet it's a carb and/or choke issue if this baby sat idle for ~4yrs. Given it goes away once hot, you gotta think choke.
I've also heard that some of these come with a tiny desiccant bag packed in the carb that is supposed to dissolve once soaked with fuel. Some leave residue that gunks up a jet or makes the float stick.
I know some of the Chinese knock-off carbs will have a bronze cap mashed over the mixture adjustment screw. You can pop it right off with a small flat blade screwdriver. It's hit/miss to what you've got. The carb on my 2009 model year 110cc happens to have accessible idle and mixture screws, but has a funky air injection system on the exhaust with a tiny catalytic converter!! The little quad is kind of [censored] as far as materials and build quality, but I'm always amazed at how well that little 110cc starts, sounds and performs!
The key to Chinese motorized toy ownership is; You NEED to be able to wrench a bit. Parts are easy to source and cheap if you've got internet access. Be sure to go over that scooter and BLUE loctite ALL critical fasteners. Blue loctite is your Chinese power sport friend.
Joel
I've also heard that some of these come with a tiny desiccant bag packed in the carb that is supposed to dissolve once soaked with fuel. Some leave residue that gunks up a jet or makes the float stick.
I know some of the Chinese knock-off carbs will have a bronze cap mashed over the mixture adjustment screw. You can pop it right off with a small flat blade screwdriver. It's hit/miss to what you've got. The carb on my 2009 model year 110cc happens to have accessible idle and mixture screws, but has a funky air injection system on the exhaust with a tiny catalytic converter!! The little quad is kind of [censored] as far as materials and build quality, but I'm always amazed at how well that little 110cc starts, sounds and performs!
The key to Chinese motorized toy ownership is; You NEED to be able to wrench a bit. Parts are easy to source and cheap if you've got internet access. Be sure to go over that scooter and BLUE loctite ALL critical fasteners. Blue loctite is your Chinese power sport friend.
Joel
Well I took the scooter apart to try to fix the warm up issue. No luck. I tried to adjust the fuel/air mixture screw and it did very little. I did adjust the idle screw up to 2000rpm when warm and now the rear tire rotates because it idles around 3000rpm for the first minute when cold then drops to 2000rpm. I have ordered a new auto choke lets hope that works!
Hi,
mez - Good news - most things like this are usually very simple - it's the diagnosis that fools most people
Enjoy your scooter
mez - Good news - most things like this are usually very simple - it's the diagnosis that fools most people
Enjoy your scooter
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