80cc motorised bike still running in,I start it it bogs out I try adjusting the idle
- Thread starter Abrahim1
- Start date
donphantasmo
Member
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
Well, Ibrahim, there are many many things that it could be.
First start with the choke. Make sure you have fuel getting in the combustion chamber, and just ride with it for a bit, pedaling, clutch out. After that, take the choke off. Not every bike needs the choke to start, but usually they do with a cold engine.
Start with that. If it runs, then dies, you may need to check your carburetor. I'm guessing you have a inframe chinease engine (But I don't know since you just said it's a 80cc). These carburetors are very easy to work on, and adjust. So, relax, it's probably something small and not expensive. Usually the kit needs a bit of adjusting and tinkering then it will run decently for a long time.
Well, Ibrahim, there are many many things that it could be.
First start with the choke. Make sure you have fuel getting in the combustion chamber, and just ride with it for a bit, pedaling, clutch out. After that, take the choke off. Not every bike needs the choke to start, but usually they do with a cold engine.
Start with that. If it runs, then dies, you may need to check your carburetor. I'm guessing you have a inframe chinease engine (But I don't know since you just said it's a 80cc). These carburetors are very easy to work on, and adjust. So, relax, it's probably something small and not expensive. Usually the kit needs a bit of adjusting and tinkering then it will run decently for a long time.
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
Sounds like you have a similar kit as me.
I am also having issues with mine.
Some advise for you to make starting easier.
Cut the plastic terminals off and solder the wires to make good connections and then insulate them.
I also had issues with the kill switch. I have since disabled this i suspect it was faulty.
Only problem i have now apx 3/4 throttle my engine starts 4stroking running rich.
I have adjusted the needle to the leanest position but same issue.
I now have ordered some smaller main jets to try out.
Pulling what little hair i have left to sort this issue out.
Will post my findings once i get the replacement parts.
Regards
Sounds like you have a similar kit as me.
I am also having issues with mine.
Some advise for you to make starting easier.
Cut the plastic terminals off and solder the wires to make good connections and then insulate them.
I also had issues with the kill switch. I have since disabled this i suspect it was faulty.
Only problem i have now apx 3/4 throttle my engine starts 4stroking running rich.
I have adjusted the needle to the leanest position but same issue.
I now have ordered some smaller main jets to try out.
Pulling what little hair i have left to sort this issue out.
Will post my findings once i get the replacement parts.
Regards
nightcruiser
New Member
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
I'm not sure what model carb you have? (the main styles are the single cable NT style or the dual cable CNS style carb) At any rate, the needle does not have much effect over the mix at 3/4 throttle to WOT, so adjusting the needle to cure the WOT bog is the wrong approach. (the needle adjusts MID THROTTLE range mix)
I would suggest you try a float adjustment to lean out your mix a bit at WOT, you want to adjust the float so the fuel level in the bowl is lower. To do this you need to bend the metal tab on the float that pushes the needle valve just a LITTLE bit. To have the float maintain a lower fuel level in the bowl you need to bend the tab in the direction where it will close the needle valve when the floats are lower in the bowl. (visualize it) SMALL adjustments are required here on the float....
I would bet that you can get your mix right by simply making a float adjustment, however, changing jets as you have suggested will also work.
EDIT: BTW, the proper way to tune one if these carbs is to FIRST adjust your carb so the WOT mix is right by adjusting the float or jet, then set the needle for mid throttle mix, then set the idle and air mix screw for best idle.
I'm not sure what model carb you have? (the main styles are the single cable NT style or the dual cable CNS style carb) At any rate, the needle does not have much effect over the mix at 3/4 throttle to WOT, so adjusting the needle to cure the WOT bog is the wrong approach. (the needle adjusts MID THROTTLE range mix)
I would suggest you try a float adjustment to lean out your mix a bit at WOT, you want to adjust the float so the fuel level in the bowl is lower. To do this you need to bend the metal tab on the float that pushes the needle valve just a LITTLE bit. To have the float maintain a lower fuel level in the bowl you need to bend the tab in the direction where it will close the needle valve when the floats are lower in the bowl. (visualize it) SMALL adjustments are required here on the float....
I would bet that you can get your mix right by simply making a float adjustment, however, changing jets as you have suggested will also work.
EDIT: BTW, the proper way to tune one if these carbs is to FIRST adjust your carb so the WOT mix is right by adjusting the float or jet, then set the needle for mid throttle mix, then set the idle and air mix screw for best idle.
Last edited:
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
Thanks for your reply.
It has an NT carb on it.
I tried adjusting the float but the result was the same.
I pushed those brass (tangs) i think thats what they are called a little lower.
I had the carb stripped yesterday and gave it a good clean out.
I tried the solder method on the main jet and left a small hole in it.
I didnt have a drill small enough but i used a fine piece of wire to push it through the solder whilst it was hot using a heat gun.
It improved a little but im not quite there yet.
I will have another go at it tonight when i get home from work and see if i have any success.
Aside from the above i will have to wait till the parts arrive and go from there.
Whats intresting when i first set it up initially it wasnt 4stroking after that it started doing it and now i am having difficulty trying to resolve the issue.
Hopefully my persistance pays off.
Regards
Thanks for your reply.
It has an NT carb on it.
I tried adjusting the float but the result was the same.
I pushed those brass (tangs) i think thats what they are called a little lower.
I had the carb stripped yesterday and gave it a good clean out.
I tried the solder method on the main jet and left a small hole in it.
I didnt have a drill small enough but i used a fine piece of wire to push it through the solder whilst it was hot using a heat gun.
It improved a little but im not quite there yet.
I will have another go at it tonight when i get home from work and see if i have any success.
Aside from the above i will have to wait till the parts arrive and go from there.
Whats intresting when i first set it up initially it wasnt 4stroking after that it started doing it and now i am having difficulty trying to resolve the issue.
Hopefully my persistance pays off.
Regards
nightcruiser
New Member
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
If you are going to solder closed the main jet you need to drill it back out with machinist drill bits so you can make the jet a particular size, you can't just "leave a small hole" in the jet. At any rate, if you have new jets coming then I would try a smaller one and see how that works out. Also, make sure your air filter is clean and not oil soaked if you are running rich...
If you are going to solder closed the main jet you need to drill it back out with machinist drill bits so you can make the jet a particular size, you can't just "leave a small hole" in the jet. At any rate, if you have new jets coming then I would try a smaller one and see how that works out. Also, make sure your air filter is clean and not oil soaked if you are running rich...
maniac57
Old, Fat, and still faster than you
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
The first thing to remember is these motors need several hundred miles to start running right. You should break the motor in before you try tuning. Several of my builds have had idle problems which disappeared once the motor was broken in. Try swapping the carb with a known runner and see if the problem persists.
The first thing to remember is these motors need several hundred miles to start running right. You should break the motor in before you try tuning. Several of my builds have had idle problems which disappeared once the motor was broken in. Try swapping the carb with a known runner and see if the problem persists.
crassius
Well-Known Member
Re: 80cc motorised bike still running in,I start it it bogs out I try adjusting the i
I stick a screw driver into the carb, mark with my thumbnail how far it went in, then put a scratch on the manifold at that depth - when carb is installed, it has to go on right up to that scratch.
not a hard process
I stick a screw driver into the carb, mark with my thumbnail how far it went in, then put a scratch on the manifold at that depth - when carb is installed, it has to go on right up to that scratch.
not a hard process