Topic: Danielle CB550K Build - Toyon Moto Club #5

[Blackfin5]

After a couple long rides yesterday, all I can report is the bike handles exceptionally well.  I am giddy with delight.  The jetting is a little off compared to last year.  A bit rich.  I tried opening the air screws 1/2 to 1 turn, which seems to help lower end response, and now taking off the bowls to drop the mains from 115 to 105 first, then depending on how it responds, back to 110 after looking at the plugs.  Leaving the needle alone for now which is a Y8 at clip #3.

[Blackfin5]

Boy, am I bad at jetting.  Felt rich.  Turned out air screws, and she ran worse.  Then turned in 1/2 turn more than where I had them to start.  Ran better but not perfect.  Pulled plugs.  They all look slightly lean.

[Blackfin5]

Closer.....

[Blackfin5]

All sorted . . . I think.  It's based on plug chops at various throttle positions and butt dyno.

As a frame of reference, this 550's engine has JE 592cc pistons, lightened and balanced APE crank, Carrillo balanced rods, a MRieck Stage III head with +1mm valves, and a Web 358b cam grind, and CR 26 smoothbore carbs.

What I ended up with:

Main jets - 110
Pilot jets - 65
Needles - Y8 on 4th (middle) clip.
Air jets - 220
Starter jets - 35
Slides - 2.0
Air Screw - 1.5 turn out
Idles at 1300 to 1400 very well
No vacuum leaks

She idled better with 55 pilots at 1100-1200, but off idle as you roll on to 1/4 throttle, she runs better with 65 pilots.  Go figure.

I'm very happy.  Pulls evenly throughout the range.