- Location
- Marion, Ohio
So I've got a pair of 44mm Blackjacks on a B-piped 840cc running Art's recommended jetting for my setup. The carbs were bought used but supposedly freshly rebuilt by Art (receipts were shown and the internals looked new). The jets and setup seem really close and I've put about 25 gallons through it with no real issues. The ski starts easily, idles fine, and the throttle response is instant even after putting around at 1/8-1/4 throttle for a while. Top end seems pretty decent too. I'm pretty sure the pop off pressure is around the high 20's, but there isn't a clear cut pop like I'm used to, more of like a slow bleed off as it gets closer to the pop pressure then it bleeds off faster. Needles were kept wet. Should I replace the needles? Idle screws are about 1 turn out, mains are about 1.5 if I remember correctly.
Here are the tops of the pistons:
Here are the tops of the pistons: