What would you do?

I've re-jetted, raised the needle, and have the BS34's working well, but may want to upgrade at some point, and maintain the option of using the air box. I wonder what make/model and size carburetor would be the best choice to replace the BS34's, while keeping cost reasonable. I would rather find a used carburetor set on ebay, instead of buying new.

Would Smoothbores be the best choice?

I'd prefer to keep the stock single-cable throttle system, unless a push/pull replacement throttle unit is available with a start/kill switch, specifically designed to replace the original unit.

The KZ1100-A2 motor is stock. Upgrades to date include a V&H header/baffle (no glass wrap), and Dynatek 2000/Mini-coils, and misc. minor things.

HELP! :blink:

You would be best served by staying with the BS34s. If you feel the need for more fuel, consider the DynoJet Stage 1 or Stage 3 kits instead. BTW, the Stage 3 kits have all the jets for doing the Stage 1 jetting, so you would be best served by just getting it while you are at it.
The smoothbores would be a step backward IMHO.

koolaidkid

Its probably a lot to ask, but...

How effective are the Dynojet mods at enhancing engine performance throughout the range, and do they create any adverse tuning issues? With a kit installed, will acceleration be smoother, or will there be dramatic power surges as the throttle is opened and closed?

I want to run with the stock air box, so does that require a Dynojet Stage-2 setup? I only see Stage-3 in the 2310 Dynojet web instructions, and it appears that changes are limited to the main jet/needle, and vacuum slides.


Thanks

I cant speak for the KoolAide Kid, but I used a dynajet kit on my Mrs's little GPZ. It has a Kerker 4-1 and always had a little stumble just off idle. The DJ kit has eliminated the stumble. That's been my experience with them. Paul

slayer61

Is Mrs's little GPZ an 1100? Was it a Stage-3 kit you installed?

There is no Stage 2. Not sure why, but that is the way it is. There are many changes that it provides, mostly the needle. Its taper is far better than the stock needle, plus it is fully height adjustable, for fine tuning the needle. Also raising the diaphragm quicker and letting a bit more air in right off idle.
I have a Stage 3 in my GPz. It has pods and a pipe, which requires the Stage 3.
Tuning is the issue. I have a wideband, aka a sniffer, so I used it to dial in the carbs. If you do not have that luxury you have to do plug chops, which are quite tedious.
But I would never, ever go back to stock Mikuni parts.
The kits are around $125, a few sets of plugs, some patience and understanding of how the Mikuni CV carbs work, and you will be grinning from ear to ear.

Will use of the Stage-3 kit require changing over to pods, or can I still use the air box?

It doesn't really matter the size of the motor. The same is true across the board, for all brands with the Mikuni carbs, such as those off-brand Suzukis. :lol:
The Stage 3 kit contains the main jets required for a Stage 1 also.
Pods or a pipe, install the Stage 1 jets. Pods and a pipe, install the Stage 3, which is mainly changing the mains and retuning the needle.

Now I'm starting to get excited...

I've got a stage 3 kit on my '78 650 with an overbore, pipe, and pods. It's made a huge difference in performance, especially when you hit into the upper range (with the needle taper being thinner). Pulls a lot smoother, with good response over the range. Agreed with what's been said- the stage 1 should be fine, but I'd get the stage 3 if you ever did any more mods to the bike.

Getting the Stage 3 kit to begin with allows you to set the other parts aside. If you ever go to pods, just pull the box out, follow the instructions, retune, put the box back. The difference in price is minimal, if any at all.