Engine Trouble Bike wont go faster than 24mph with 36t sprocket

[6blueoval9]

Okay, i really appreciate your help

Youre welcome...let us know how it turns out.

 

[BikePete]

Ok

 

[BikePete]

Hey i lowered the jet to the 64 and my top speed was 26-27mph a bit better. Heres my plug afterwords. U think its lean? I rode the bike for 10minutes after letting warm up for 5minutes

 

[6blueoval9]

The color on the second pic looks sort of white which would be lean...get a jet kit and start one size under the 70 till its right...id put the 70 back in till you get jets.

 

[BikePete]

Will do but i dont understand if im a bit lean shouldnt i have had a higher top speed than that?

 

[6blueoval9]

Depends...you may have some other issues that i cant see but running lean to a certain degree will make more power just not safely

How old is the motor?

What oil and fuel ratio mixture are you using?

 

[BikePete]

4 ounces in a gal and its fairly new i probably have about 200 miles on it. The piston and cylinder look good but i see burn marks on the piston rings threw the Exhaust port. Is that ok?

 

[6blueoval9]

Any chance you have a compression gauge to check cranking pressure?

I would think it would do better than that speed but something else could be wrong with it...none the less, the carb needs to be tuned properly to get all you can out of it.

 

[6blueoval9]

Might just be carbon on the rings..not sure.

 

[BikePete]

Sadly no. I wish i had a gauge to test it.