I used to run my old DT250 35 miles to the next town. Crused 55 to 60 mph, speed limit was 55. Air cooled, oil injection, never heard of varying the rpm, pulling in the clutch, or applying the choke. It's a wonder I didn't go up in flames Are you really running with the throttle wrapped clear around? Find a comfortable cruising speed and don't rap it out tight. Unless you are running lean on the top end of the throttle opening I can't see where you would get into too much trouble. Both bikes you are talking about are water cooled aren't they? Thought those bikes were "enduro" types were it could see a long stretch of high speed through desert like conditions.