I was wondering if anybody knew the proper DeLLorto carb sizing for a stock port '83 12a motor. Is a 50 mm to large? Thanks.

 

For the 12a the Dellorto RB sold was a DHLA 48mm with, I think 37mm chokes. 50mm would be too much for a stock port I think. You'd never get the drivability on the low end because the air velocity wouldn't be high enough. Of course that depends on the chokes used in the carb. You also want to make sure its a RB prepared Cell or you'll be doing a lot of work perpping it to work with a rotary.

 

it's a 48mm carb with 39mm chokes.

www.gruntled.com has lots o dellorto specs.