Needle supposed to have this many washers?

[The Standard]

@5twins appreciate the thorough insight on this as well as commentary from others on this thread. Looking forward to making these adjustments and fine tuning and will report back on result.

Have a set of VM34's begging to get off the shelf and installed but feeling like I have a much deeper grasp on dialing these BS34's for as much performance as they are capable of.

Just out of curiosity, are the VM34's the go-to induction setup for this application because the manual activation of the slides over the vacum diaphragm activation with the BS34's more immediate and the greater number of circuits for fine tuning? Assuming the common "34" in naming convention means they both flow the same CFM?

I recall from my auto hotrod days manual secondary performance 4-barrel carbs like a Holly Double Pumper were choice for hot motors over vacum secondary versions.

If this has already been thoroughly covered in a different thread please advise.

 

[The Standard]

@5twins, one additional question on the fine-tuning effort here for me. For this round of tuning I only have additional 130 Air jets (2 sizes down from stock). You mentioned having to go back up 1 size (132.5) in your tuning to get the smoke ring back down to bottom 1/4 of the insulator.

What running condition of the bike was observed with the 130 air jets installed? Stumble anywhere or flat?

Wondering if the extremely high-flow combination (extra lean) of medium length open velocity stacks and open 36" length TT pipes will support the 130 air jets. I am pretty much at sea level/ slightly above.

Other jetting installed presently:
135 air jets
137.5 mains
45 pilots
mixture screw plug removed - set at 3 turns out
Stock cam/compression

 

[5twins]

Tuning and then fine tuning carbs is all about experimenting. Every one of these motors responds a little differently depending on it's internal condition. There were no ill running effects with two sizes down on the air jets, just the plug color was off (smoke ring too high). Yours may be fine with it though, so you'll just have to try it and see.

Although I've never tried them, as far as the VM carbs having quicker and better response goes, I'm perfectly happy with my CV carbs. When I whack the throttle open, the bike immediately goes, no lag or balking before it responds. Frankly, I don't see how it could be much better or quicker, but folks say they are. Maybe they just didn't have their CV carbs tuned well enough?

I think you're doing the right thing by trying to dial in the original CV carbs. There aren't all that many variables and tuning items on them to deal with compared to the VMs. With all the tuning parts available for the VMs, you could spend years and probably still not try them all or get them perfect, lol. But thankfully, there is a baseline worked out for them, so to dial them in you shouldn't need to stray too far from that.