I was wondering if any of you modified your main jet I would like to go down a size, but I dont' want to hurt any engine reliability, what are all you 600ho riders running?
What is safe

lean is mean until you blow it up.

Here are two posts that may help you [url=http://www.hardcoresledder.com/forums/index.php?showtopic=175613]http://www.hardcoresledder.com/forums/index.php?showtopic=146337&hl=

400 mains with tempa flow

390's..................

Look at your spec chart that came with the sled and use the altitude and temp you will be riding in. 390 to 400 is norm for below 2000'

what would you do if the sled had zero miles? wait a couple hundred miles and switch, or go to town now?

Run it in first- 500 miles- then switch

Yes, run the stock jets for a tank or two of gas.

Keep jetting down until the DET flashes. Then jet up one size. You'll probably end up with 380 mains. I agree though. Put a couple hundred miles on the sled first.

Is the DET that reliable that you can depend on it for jetting?

I found that it works awesome. Very quick acting.

400 mains and 45 pilots air srews 1/2 turn

390's, 35 pilots

390's

400 mains with a Tempa Flow. Works good for me at WI riding elevations.

Add a gutted airbox to the above for me

May try 400 mains again this year but I didn't like what I saw when I ran them during
some testing last year....