2-Stroke Engines (Won't go more than 25 MPH)

[Nathanbub]

so I just did my first build of hundred cc motorized bike conversion kit and I did about 22 heat cycles to make sure the motor was completely broken into and I am just now starting to go full throttle but my friends are going way faster than me and I am stuck down at 25 mph I don’t know what to do and I’m worried that one of the cylinder rings didn’t set does anyone know how to fix this or know the problem thanks

 

[mony0_3]

Which 100cc engine, YD 100 or Steel Sleeve?

 

[Sidewinder Jerry]

so I just did my first build of hundred cc motorized bike conversion kit and I did about 22 heat cycles to make sure the motor was completely broken into I am just now starting to go full throttle but my friends are going way faster than me and I am stuck down at 25 mph I don’t know what to do and I’m worried that one of the cylinder rings didn’t set does anyone know how to fix this or know the problem thanks

What size are your tires?
What size is your rear sprocket?
Do your friends have the same size tires?
Are they using the same size rear sprocket?
Are you a lot heavier than them?

 

[FrizzleFried]

...have you adjusted your carb needle for your altitude? I found an extra 4+ MPH when I leaned mine out one notch.

 

[Nathanbub]

What size are your tires?
What size is your rear sprocket?
Do your friends have the same size tires?
Are they using the same size rear sprocket?
Are you a lot heavier than them?

yes we have all the same tires and all the same 36 tooth rear sprocket and I weigh about 16 pounds less than them

 

[Nathanbub]

...have you adjusted your carb needle for your altitude? I found an extra 4+ MPH when I leaned mine out one notch.

no my carburetor needle is at the right spot

 

[Sidewinder Jerry]

yes we have all the same tires and all the same 36 tooth rear sprocket and I weigh about 16 pounds less than them

So what size tires do you have?

 

[DAMIEN1307]

no my carburetor needle is at the right spot

I am curious as to how you ascertained that you have the C clip in "the right spot" as I see your right at or about actual sea level based on your location.

The picture below shows a needle valve that has 5 positions to put the C clip, tell me which one yours is clipped into please.

 

[Sidewinder Jerry]

I thought you meant the needle on my choke I'm not sure how to find the c clip and where it is

You never did tell me your tire size??? I'm going to assume 26" tires which with a 36t rear sprocket topping out at 25 mph; means the engine is turning 4771 rpm. A broken-in engine with a tuned carb should at least turn 6000 rpm.

 

[DAMIEN1307]

I thought you meant the needle on my choke im not sure how to find the c clip and where it is

Its at the end of the throttle cable that fits inside the barrel slide that then is inserted into the carburetor...You would have had to put that altogether yourself....I have not got a clue what you meant by "needle on my choke" since that is merely an up and down lever with nothing to adjust.

So unscrew the top of the carburetor, pull the barrel slide out, and tell us what slot the C clip is in so we can help you with the proper carburetor adjustment before you put it back together.