Which needle is richer?

[DogBunny]

5J10 or 6H2, which is richer?

I am working on a 1976 XT500, Carb is a VM34-SS Frankenstein, it is supposed to have a 5J10, instead it has a 6H2 from a 1977 VM32-SS. Thanks in advance.

 

[5twins]

Measure the length, longer is usually leaner. The first number in a Mikuni needle code represents the needle series, and they go in 10mm increments. A 4 series would be between 40 and 50mm long, a 5 series between 50 and 60mm, a 6 series between 60 and 70mm, etc.

 

[DogBunny]

Thank you.
The 6H2 is 62mm long.
I do not have a 5J10 to compare to, but I am going with what you said, and will assume that the 6H2 is longer and leaner.