So I'm not to familiar with combustion engines of any kind, and well I purchased an 80cc gas powered engine from ebay and a bike from walmart. I paid my friend to assemble the bike, I have owned it for about a month and about a week ago i was headed to work which is about 4 miles from my house. When I got about 100yds from my work when my bike stalled out and I haven't been able to get it started since then, I have checked the fuel line, the spark plug and have no idea how to diagnose it. Anyone have any ideas? I could really use the help!
Im new at this and I am looking for help...
- Thread starter DrkJEDInght
- Start date
Is there a local auto shop or lawn mower repair shop that you use? If not you will need to give everyone here as much info as possible on your bike and we will do what we can to help. Oh and welcome to the forum, Greg.
there are SO many things that can cause this, but i'll ask the obvious.
first of all, is this a 2 stroke china engine?
since you say that you are unfamiliar with combustion engines or 2 strokes, you DID mix 2 stroke oil with your gas at a 32:1 or so ratio right?
is the choke on the carb stuck closed?
does the spark plug have spark? (there's an easy procedure to determine this).
are any bare wires touching the frame or the engine?
did your friend use the push together wire connectors that come with the kit?
if so, are they still plugged together?
(those wire connectors should never be used. all wire connections should be soldered together, and covered with heat shrink).
is there anything (like a headlight) hooked to the white wire coming out of the engine where the rest of the wires come out. if so, whatever is hooked to the white wire should be removed, and the white wire shoudl be cut and capped off.
since you're not familiar with engines, i hate to ask if you have gas in the float bowl in the carburetor. It is possible that the float is stuck closed, which would allow the needle & seat to stay closed and no gas will flow into the float bowl. it's also possible that there's a peice of dirt stuck in the needle & seat, which would allow no gas to flow into the carb. The main jet could also be plugged with dirt.
was the gas tank fushed out before gas was put in ot for the first time? these gas tanks are known to have a lot of debris and paint chips inside of them.
do you have an in line gas filter?
is it plugged up?
is there gas flowing out of the gas tank through the fuel line? (there's another simple procedure to check this)
like i said, there are a ton of things that can cause your problem...we need to get more specific to diagnose it.
but if you don't know about engines, we may not be able to help you because you may not understand what we are talking about.
more than likely, it's something simple that can be fixed by you with a little coaching and help. these engines are not that sophisticated, they are simple little things, but they do require lots of tinkering and tuning to keep them running.
if you bought this under the assumption that you could just bolt it to a bike, throw some gas and oil in it and ride it with the reliability of a car or a motorcycle, then you've been mislead.
first of all, is this a 2 stroke china engine?
since you say that you are unfamiliar with combustion engines or 2 strokes, you DID mix 2 stroke oil with your gas at a 32:1 or so ratio right?
is the choke on the carb stuck closed?
does the spark plug have spark? (there's an easy procedure to determine this).
are any bare wires touching the frame or the engine?
did your friend use the push together wire connectors that come with the kit?
if so, are they still plugged together?
(those wire connectors should never be used. all wire connections should be soldered together, and covered with heat shrink).
is there anything (like a headlight) hooked to the white wire coming out of the engine where the rest of the wires come out. if so, whatever is hooked to the white wire should be removed, and the white wire shoudl be cut and capped off.
since you're not familiar with engines, i hate to ask if you have gas in the float bowl in the carburetor. It is possible that the float is stuck closed, which would allow the needle & seat to stay closed and no gas will flow into the float bowl. it's also possible that there's a peice of dirt stuck in the needle & seat, which would allow no gas to flow into the carb. The main jet could also be plugged with dirt.
was the gas tank fushed out before gas was put in ot for the first time? these gas tanks are known to have a lot of debris and paint chips inside of them.
do you have an in line gas filter?
is it plugged up?
is there gas flowing out of the gas tank through the fuel line? (there's another simple procedure to check this)
like i said, there are a ton of things that can cause your problem...we need to get more specific to diagnose it.
but if you don't know about engines, we may not be able to help you because you may not understand what we are talking about.
more than likely, it's something simple that can be fixed by you with a little coaching and help. these engines are not that sophisticated, they are simple little things, but they do require lots of tinkering and tuning to keep them running.
if you bought this under the assumption that you could just bolt it to a bike, throw some gas and oil in it and ride it with the reliability of a car or a motorcycle, then you've been mislead.
DRKjedi, First, Welcome to THE Forum. We have Never turned a New Member, or anyone else away! If it is broken, we can fix it! You have some good info, so far, I would like to point out the tank might have fuel still, But if it drops below a level of flow, the Petcock will not feed the motor. Check that as well. Just ask and we will help. 
First off I want to welcome you to the best MB forum I could find. Not only do we have a wide range of knowledgeable members, but also and the most active, should you have questions, the response time is really fast.
We have numerous “stickies” that cover just about any aspect on all MB’s, along with a “SEARCH” function. Although at times it isn’t the easiest to use. This is due to that the title of the post that isn’t specific enough. Posting titles like “Help” doesn’t help others doing a search, and I and others tend to pass them up at times, only going back a later time, which makes an answer longer to get.
Should you have a question, and to make it easier on members, Please state specifics about your subject, such as if you have a engine problem, tell us what engine you have, along with any other important information that we night need to help you, like what carburetor you have, if known. A picture is always helpful. Like the saying goes….a picture is like a 1000 words, also we may see something that might needs to be addressed. Believe me; it happens more often then you think. We know that there are those that are not that knowledgeable, or are mechanically challenged (unusually, PC correct :>), so there is not a stupid question, although I do think that sometimes there are some, so bear with me. Hey what do you expect with 50 years of wrenches in my hands, but we all had to start somewhere.
For those that are not knowledgeable on the terms of parts on a China 2 cycle (some are specific to these HT engines), here is a link that lists about every HT part. It is real hard for me to understand what a “thingy”, “whatcha ya call it” “thing of a jig” is.
http://www.bicycle-engines.com/2stroke-parts-c-4.html?osCsid=ges5a73qhdeuvshi19srjuq544
I have a link in my signature that everyone starting out with a Chinese 2 cycle ought to read. Most are also included in many of the “stickies” This deals with pre installing a HT engine in the frame, engine not running correctly and more.
Once again, welcome to the world of MB’s, and have a safe, enjoyable riding experience.
Ron
We have numerous “stickies” that cover just about any aspect on all MB’s, along with a “SEARCH” function. Although at times it isn’t the easiest to use. This is due to that the title of the post that isn’t specific enough. Posting titles like “Help” doesn’t help others doing a search, and I and others tend to pass them up at times, only going back a later time, which makes an answer longer to get.
Should you have a question, and to make it easier on members, Please state specifics about your subject, such as if you have a engine problem, tell us what engine you have, along with any other important information that we night need to help you, like what carburetor you have, if known. A picture is always helpful. Like the saying goes….a picture is like a 1000 words, also we may see something that might needs to be addressed. Believe me; it happens more often then you think. We know that there are those that are not that knowledgeable, or are mechanically challenged (unusually, PC correct :>), so there is not a stupid question, although I do think that sometimes there are some, so bear with me. Hey what do you expect with 50 years of wrenches in my hands, but we all had to start somewhere.
For those that are not knowledgeable on the terms of parts on a China 2 cycle (some are specific to these HT engines), here is a link that lists about every HT part. It is real hard for me to understand what a “thingy”, “whatcha ya call it” “thing of a jig” is.
http://www.bicycle-engines.com/2stroke-parts-c-4.html?osCsid=ges5a73qhdeuvshi19srjuq544
I have a link in my signature that everyone starting out with a Chinese 2 cycle ought to read. Most are also included in many of the “stickies” This deals with pre installing a HT engine in the frame, engine not running correctly and more.
Once again, welcome to the world of MB’s, and have a safe, enjoyable riding experience.
Ron
See if the spark plug cap came off. The top of the engine is called the cylinder head, and that is where the combustion happens. The spark plug ignites the fuel air mix, and without a spark the engine won't run. The spark plug is what makes a spark, as the name might suggest. Just Google "spark plug" to see what it looks like, I can't post pictures from my phone. There is a black cap that goes on the spark plug, and it carries the high voltage electricity the the spark plug to make a spark. Make sure it is connected good. The little black box that the cap is connected to by a wire is the CDI, and what it does is take low voltage from the engine magneto and turn it into high voltage so it makes a strong spark. The wires that connect the cdi to the engine must be connected well, blue wire to blue wire and black to black. The white wire is for accessories, so it should be taped up if not being used. If it touches any metal on the bike, it will short circuit and then you will not have a spark, or a weak spark at best. There are also wires that go to the kill button to stop the engine, all they do is short circuit so the engine stops making a spark. It doesn't matter how they are connected as long as one wire connects to the black wire and one goes to the blue wire. An easy way to make sure you are getting a spark is to unscrew the spark plug with a wrench, counterclockwise to loosen it, and put the cap on then turn the engine by turning the pedals with the wheel off the ground and the clutch lever out. The spark plug has to be touching part of the engine to make an electrical connection for the spark. Don't worry about eletricuting yourself, it is very low power even though it is high volts, all it can do is give a little jolt but no harm. Hope you get it fixed soon to enjoy this nice riding weather!
YGM
YGM
thanks to all your ideas, im gonna get out there and try some of these ideas. to dragray thanks for all those suggestions and i have mixed gas but its at a 50:1 ratio is that bad, ill need to check the needle and seat cause it does seem to be having a hard time getting gas to the carb, and the wiring is fine thats about the only thing i know for sure.. once again thanks to all you guys and if any more ideas come up then just lemme know
my engine is an 80cc china engine, i got it off ebay... there is a lot of Chinese symbols on the choke and im not sure but i think i could have a defective cdi coil...
Choke handle pulled up. choke on, restricts air flow (general used when starting the engine)
Choke handle pushed down, choke off, max air flow (used when engine warmed up and traveling.
Check out coil and CDI...use a multimeter. Read my link on Engine running problems?.
Last edited:
Running 50:1 may have damaged the engine, it needs more oil for break in. What kind of oil is it? If it is cheap stuff from a gas station, I wouldn't be surprised if the engine is damaged, but it would have been a gradual decrease in power from loss of compression unless you have bearing failure. In that case, you will need to take apart the engine to find out what is wrong. Take it to a small engine shop if you aren't comfortable with taking apart the engine, but it is very simple. Read up a lot on the troubleshooting and repair threads. Good luck!
YGM
YGM
I wouldn't start with 50:1 mix (I use a 20:1 mix then on to 32:1), but I don't think that mix will damage the engine, I could be wrong tho. Some are using 100:1
Last edited:
What happened when the engine cut out on you? Did it start loosing power a minute or less before it died? Or did it suddenly lock up? Or did it just stop firing and slow to a stop? If you describe exactly what happened, that can help diagnose the problem. Also, 50:1 is not enough oil unless you have really good synthetic oil.