Hey guys just finished mounting my bike kit on my beach cruiser. Mixed the gas perfectly, but for some reason I am not getting enough RPM when turn the throttle. Can you please tell me what I am missing here? Do I need to break the engine in or something?
No RPM on my new 2 stroke engine HELP!!
- Thread starter marluzkat
- Start date
you need to break the engine in.
Do you mean the rpms are just off idle.
Or not high enough for your liking.
I would check the following.
With the engine off. remove the airfilter.
Look down the carb bore.
Is the choke closed or open.
Move the little handle up and down.
Leave it open.
Twist the throttle does the throttle slide move up and down.
Close the fuel petcock.
Unscrew the two screws holding the bottom of the carb on..
Remove the bottom of the carb.
Open the fuel petcock.
Does gas flow freely.
Close the petcock.
Reinstall the bottom of the carb.
Reinstall the airfilter and try again.
You may need to glue the carb to the intake manifold with rtv.
Do you mean the rpms are just off idle.
Or not high enough for your liking.
I would check the following.
With the engine off. remove the airfilter.
Look down the carb bore.
Is the choke closed or open.
Move the little handle up and down.
Leave it open.
Twist the throttle does the throttle slide move up and down.
Close the fuel petcock.
Unscrew the two screws holding the bottom of the carb on..
Remove the bottom of the carb.
Open the fuel petcock.
Does gas flow freely.
Close the petcock.
Reinstall the bottom of the carb.
Reinstall the airfilter and try again.
You may need to glue the carb to the intake manifold with rtv.
I added a extra gas filter. I will remove it and see what Happens I will keep you posted. I also noticed that there is a little back fireing in the muffler too.
Qustion for ya do you have the CNSv2 carb with the red air filter cover ? If you do that is the root of your troubles, You can spend day's trying to get it right,, "Wont happen" Spend a little more $ and get a NT carb you will be happy and so will your motor, I hear a lot about intake air leaks. These little 2 strokes dont seem to mind a little extra air, Even if it is aroung the carb to intake seal. Defentily remove the filter from the pet cock and install a inline the stock filter's just wont let enough fuel pass, gas to oil is extra important I run 3 1/2 oz's of oil to 1 gallon of fuel premenum grade. Also swap out the LD spark plug for a NGK you can find what # NGK by going to spark plug's here at the forum.
Just a little wisdom from
The bike surgeon
Thunderbolts
Just a little wisdom from
The bike surgeon
Thunderbolts
Great thank you so much Thunderbolt. I will try this out where can I buy the NT carb? I will change the ratio on the oil with premium gasoline too.
I'll have to disagree with the theory that these 2 stroke engines don't mind a little extra air. Any air leak in the intake system will seriously effect the way the engine runs. The carburetor should be sealed to the intake manifold and the manifold to the cylinder. I do agree that there seems to be a lot of dissatisfied owners of the CNS carbs but there are a lot of guys running them and doing so without problems.
Heed the advice given by Spad4me. Let us know what you find.
Tom
Heed the advice given by Spad4me. Let us know what you find.
Tom
Just a note I have a cousin that has worked on 2 stroke boat motors for 30 + years, we were talking talking about the carb to intake air leak and we got talking about the old Johnson's and evinrude's where the carb's didn't even have a clamp and would sometimes fall off. These carb's pulled air around the intake and carb. I have a pre 2010 66 cc with a NT carb It air leaks where it should not, carb cleaner will kill the motor there's no seal of any type this motor runs like super I also have put this same carb on a new 66 cc sky hawk and it runs OK better than the last one i did and put the CNSv 2 carb on and I did seal all air leaks on that one, there is a NT on it's way from bike berry NOT KINGS I have always been taught that if you have a air leak pre carb it will screw thing's up adjustment's, to much air from the wrong place So I do agree that any motor pulling air any place but from the intake of the venture of the carb. But why does the old 66 cc run so good and why does the new sky-hawk run better with it than the CNS ? I have been told that with the CNS carb you need to run the choke in different positions depending on the riding condition and load. I am a newbie here but I have had my share of 2 stroke gas on my hand's Again if you buy a NT get it from bike berry and remember until your new motor is broke in it will not run 100% . Are you running a ngk spark plug, did you remove the filter on the petcock and install a in line, Have you tried resetting your needle on the carb slide ? But most of all ride it !!!!! and do your best to seal that air leak, But a little wont hurt. I hope this helps you some. But this is just me everyone has there own opinion .. GOOD LUCK and glad to help if I have
Great thanks again Thunderbolts I will check with Bike Berry and take your advice on everythng. I will keep you posted.
I may be concidered a newbie here but like I said I have had more than my share of 2 stroke proplem's and plenty of 2 stroke gas on my hand's
First I would like to apoligize to Lord Norm, I guess this is his page and he has the force behind him. :0) Sorry Norm!!! Marluzkat I would like to keep helping you so I will start a help forum, I will take the Vadors advice, oh buy the way luke skywalker thanks for the comment I do have thunder ball's. Marluzkat I'll contact you.
Your more than welcome.
Maluzkat notice the info by the members with more experience, or the number of posts. 2Door and Spad4me. I'd listen to them.
I would not start throwing money at the engine hoping for a fix.
First there is no need to run premium gas, these engines are low compression. Regular fuel is better.
Most instructions tell you to use 16 to 1 fuel mix. I've found using 32 to 1 mix is better, after break in I use 40 to 1 using syn. 2 stroke oil.
If you have leaks on the intake tract, crank case seals, cylinder base gasket, or the split line on the crank case, that will change the fuel to air mix. It will make your engine very hard to tune.
The stock spark plug will work fine if it is not oil fowled, I use less gap 0.017 to 0.020"
You might want to check the carb's main jet find out what dia. the hole is drilled. To measure the jet you will need a set of micro drills and a micrometer. If you live above 3000' then you may want to decrease the main jet size. there is info on this forum about that. usually the stock jet size is 0.070mm the next leaner size will be 0.065mm
Some of these carb's needle is machined wrong on the taper. they will idle fine but will to rev up. Ask Palbo(one of the guys from sick boys parts) he had one. That repair was simple using a micrometer (to measure the taper) with the needle chucked in a dremel tool and 600 grit wet/dry sand paper I don't recommend doing this as it takes only about 0.002" to make a big change in the amount of more fuel that it will deliver, you need to work with a known good working needle for getting the proper measurements.
Most of these engine will work good using the #2 E- clip slot on the needle counting is from the bottom of the needle/ pointed end , If the E-clip is in the top slot then that is the leanest setting for the needle.
The fuel air ratio is effected by the needle up to 3/4 throttle, at wide open the fuel air mix is controlled by the main jet.
For a new engine they will a lot of times run crumby until broken in even worse if there is air leaks or if there is a fuel mix of 16 to 1 used, along with a wide spark plug gap of 0.028"
An inline paper fuel filter is a must, the tanks will have very fine particles of trash in them and these particles will cause problems.
Get the intake tract sealed.
Make sure the carb is assembled correctly and that the choke is not accidentally going to the choke position.
Take off the air cleaner looking in at the carbs throttle slide make sure it goes all the way up and closed.
You can also clean the foam air cleaner in warn water using a drop of dish soap, get all the oil and dirt out of it. Then either let it air dry or you can wring it out in a couple of paper towels install the filter without oiling it. Start it up and ride it for 30 minutes or so. The filter will oil itself due to the way these engines puke fuel/oil out of the carb every time the engine makes a revolution.
Maluzkat notice the info by the members with more experience, or the number of posts. 2Door and Spad4me. I'd listen to them.
I would not start throwing money at the engine hoping for a fix.
First there is no need to run premium gas, these engines are low compression. Regular fuel is better.
Most instructions tell you to use 16 to 1 fuel mix. I've found using 32 to 1 mix is better, after break in I use 40 to 1 using syn. 2 stroke oil.
If you have leaks on the intake tract, crank case seals, cylinder base gasket, or the split line on the crank case, that will change the fuel to air mix. It will make your engine very hard to tune.
The stock spark plug will work fine if it is not oil fowled, I use less gap 0.017 to 0.020"
You might want to check the carb's main jet find out what dia. the hole is drilled. To measure the jet you will need a set of micro drills and a micrometer. If you live above 3000' then you may want to decrease the main jet size. there is info on this forum about that. usually the stock jet size is 0.070mm the next leaner size will be 0.065mm
Some of these carb's needle is machined wrong on the taper. they will idle fine but will to rev up. Ask Palbo(one of the guys from sick boys parts) he had one. That repair was simple using a micrometer (to measure the taper) with the needle chucked in a dremel tool and 600 grit wet/dry sand paper I don't recommend doing this as it takes only about 0.002" to make a big change in the amount of more fuel that it will deliver, you need to work with a known good working needle for getting the proper measurements.
Most of these engine will work good using the #2 E- clip slot on the needle counting is from the bottom of the needle/ pointed end , If the E-clip is in the top slot then that is the leanest setting for the needle.
The fuel air ratio is effected by the needle up to 3/4 throttle, at wide open the fuel air mix is controlled by the main jet.
For a new engine they will a lot of times run crumby until broken in even worse if there is air leaks or if there is a fuel mix of 16 to 1 used, along with a wide spark plug gap of 0.028"
An inline paper fuel filter is a must, the tanks will have very fine particles of trash in them and these particles will cause problems.
Get the intake tract sealed.
Make sure the carb is assembled correctly and that the choke is not accidentally going to the choke position.
Take off the air cleaner looking in at the carbs throttle slide make sure it goes all the way up and closed.
You can also clean the foam air cleaner in warn water using a drop of dish soap, get all the oil and dirt out of it. Then either let it air dry or you can wring it out in a couple of paper towels install the filter without oiling it. Start it up and ride it for 30 minutes or so. The filter will oil itself due to the way these engines puke fuel/oil out of the carb every time the engine makes a revolution.
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