Finally got a chance to do some meaningful testing with the pz20. 68 degrees and 20mph wind. Still too windy to do one-to-one comparisons with my old numbers, but after all these years, I think I can make a fairly good seat-of-the-pants judgement.
When I pulled out of the garage, I fully expected to ride a block or two, then come back and make some adjustments. Apparently I was pretty lucky with my initial setup. Other than a quick stop to adjust the a/f screw, it ran great, so I just kept going.
Started out with 38/82, needle on 2nd-richest clip, a/f 2 turns out, and my short little v-stack intake. No bogging, no hesitation, no sputtering or backfire, it just GOES! Think I may need to go up a size on the main, it felt like it wanted a little more, but definitely no lean bog.
Like I said, I don't have exact numbers, but the butt-dyno reports a power increase. Noticed myself at one time doing 43 against the wind up a slight incline, and hit 47 several times with the wind. I was out right after the moms picked the kids up at school, so I had to abort almost every high-speed run. I did see 51 at one time.
Still need to do some tuning, but under the circumstances I was pretty pleased. Seems to be potential to out-perform the stock carb. Of course I still don't know how finicky it will be to temp. changes and such, but for now at least, I'm leaving it on there.
I had noticed that the idle speed screw didn't fit very tight, and sure enough it kept vibrating out of place. I got to the bottom of a big hill and it died. Reached down to adjust the knob, and it was gone! Puttered up and down that hill 5 or 6 times hoping to find it, when it finally occurred to me, Hey, maybe it's on top of the motor! Sho nuff, the knob and spring were laying right there! Gotta put some gooey on that.
Anyhow, that's my first real experience with the pz20, and I gotta say, I was pleasantly surprised. I was EXPECTING a bog at takeoff, and it just didn't happen.
PS: BIG thanks to the TRBRO who sent me this stuff to play with. Like most philanthropists, I believe he prefers to remain anonymous. If not, I'll give you a big public THANKS!