Optimum range of rotations?

My dad dropped off his '12 DR650 for me to "freshen it up" if you will. I bought him a different type of choke (mounts on engine) as well as got him an extended fuel screw. Carb wise, everything is stock (whatever those parameters may be) as well as the exhaust. With that being the case, what is considered the optimum range of turns of the fuel screw for the stock carb? I wanted to try and play with the fuel screw some to get the sluggishness out of it before I went to the full jetting kit/airbox mod route. Thanks!

The optimum fuel screw setting will vary from machine to machine and with altitude . My approach is to adjust for maximum rpms then back it out another 1/2 turn (i.e. slightly richer). Then set the idle speed to spec (1500 rpms).

I normally ride at 2-4k feet. However, for the last two weeks I've been above 5k with lots of time above 7k. Running it in 1/2 turn improved idle and throttle response up there.

But, to answer your question, if the idle air circuit and pilot jets are clear and you have to open the screw more than 4 turns to achieve maximum idle speed you probably need a larger pilot jet.

Excellent... Thanks for the response!

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