surge

[Tom Thomson]

My 83 650 is surging when at any steady speed (30-40-50 etc). What could cause this and what can I do about it?
tommyt

 

[resto]

First, and easiest thing to try is driving with your gas cap slightly open. This will answer whether or not you have a fuel tank venting problem.

 

[5twins]

Surging is an indication that you're running lean. I would start by cleaning the carbs. Uncap your mix screws if they haven't been already and set them to about 3 turns out. If none of that helps, try 135 mains.