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Hi all,

I am thinking of trying grass drags this summer in stock class.
I need some pilot stage tuning tips for a 98 xcr 600.
Normally I use the "increase in RPM method" and turn in about 1/8 turn from that, after I check for to see if my idle "hangs up" or bogs after I blip the throttle. But I can't seem to hear a difference when I try to tune it now.
I wish I could just concentrate on one cylinder at a time, Do any of you know if I can put "dummy plugs" in the other 2 cylinders to just be able to listen to 1. These triples are difficult to listen to individual cylinders.

Any tricks out there for fine tuning pilot stages on triples?

It's been difficult, I try one set, sync the carbs, adjust cable, install airbox, try to tune a decent idle, sync the carbs again, Adjust one carb pilot air, and so on, and so on,
Then I need to wait for the engine temp to come down so I can start all over because I am too hot and mixture gets too rich - real difficult and time consuming

PS - its a trio of round slide vm38's

thanks
 

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If you are going to run it in the grass you will definitely have to richen up your pilots. Once you have leaned your mains down to where they should be, your motor will be starving for fuel when you first crack the throttle wide open. We always put the sled on a track stand. get the motor up to operating temp. Bring your RPM's up just under where your engagement will be. Now crack the throttle wide open. If the motor hesitates, you are too lean on the pilot jet. If it blubbers and then picks up, you are too rich. My guess is you will have to go up a couple sizes on your pilots. See if your dealer has a number for the Polaris Race Dept. Call them and they will put you in the ball park on jetting and clutching. When we ran Cats we always got a good start from talking to Al Shimpa in the Cat race dept. Usually these guys are glad to help someone get started
 
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