Kz750ish carb advice

I am in the process of putting a 750 block on my kz650 (1981 csr). So I need someone to tell me if I am dreaming about using my stock carbs or if it would work.

Carbs = vm24ss

I already purchased a dyna jet kit. Right now set at stage 1.

Could these work with the following setup =

Stock airbox
4 to 1 exhaust
Kz650 head with mild port/polish
Kz750 block

I was thinking maybe with the stage 3 it would work??? Stage three shows 122 (jets) and a certain needle setting.

If I am just dreaming I need to know so I can just try to sell the vm24's and buy something bigger...

Thanks,

Jeff

elr658 over at the kawasakimotorcycle.org site is using VM24 carburetors on his 750-4 Ltd --- he's is one of the more knowledgeable Kaw guys around. I do not know what jetting he used.

Instead of the kits, I would install larger jets & maybe shim the jet needles to raise them.
For reference & in general, a KZ650 with pod filters & 4-1 exhaust typically uses ~115 main jets, #17 pilot jetss & the needles are raised 1 groove above stock (ie, clipped 1 groove lower on the needles). The CSR jet needles don't have grooves, so you'd have to shim them with small washers --- probably ss.

Instead of the kits, I would install larger jets & maybe shim the jet needles to raise them.

That's what I'd do too, maybe change the needle profile if jets and shimming doesn't sort it.

A freind of mine had just this set up, the bike was really nice and tourquey and the carbs tuned really nice. He used an air corrector kit too, but he was running velocity stack bellmouths - no airbox. The dynojet kit might have this, or a drill bit to enlarge the air jets.

Well, I already have the stage 3 kit from dyna jet so I have the adjustable needles. The stage three setting is 122 main jets with two marks and a washer on the needle. Sounds like with a little adjustment the vm24 carbs may work.

Just to add another twist to what is already quite a complex problem; dynojet have a different jet numbering notation so it isn't a like-for like numerical comparison on main jet sizes.

Oh great. Is there a reference sheet somewhere?

I have the stock jet in the carbs right now. I can't really tell the difference between the 118 and the 122. Maybe an elevation adjustment? I am in salt lake city so I am at a higher elevation.

That instruction sheet is for a KZ650. [strike]Wouldn't you need kits for a 750?[/strike]
my mistake. a kit for a 750 isn't going to work on vm carbs. doh.

Jet x-ref. Do an internet search for Dynojet mikuni conversion chart or something like that. From what I've been able to ascertain, Dynojet numbers are based on the actual diameter, whereas Mikunis are based on flow rates.

Here's a topic with a chart but I do not know its original source. thegsresources --- GS850 Jet Kit work around Questions.

I have the 650 carbs. I was hoping that I could re-use those with bigger jets so I don't have to buy different ones....
I already have the vm24ss carbs and dyna jet kit I purchased many years ago...

Jeff

Lou here has a jet conversion chart on his 550 website, plus a lot of other interesting info.

Ive seen a reccomendatin of Jetting for a kz750 with pods and exhaust as 70/140 on the cv34s keihins they come with.... Stock is 68/125? I think?

My 750r1 CV34mm is on 137.5 mains with pods and a 4-1 pipe, seems a big step over stock I know but this has been discussed recently here and the other poster was using a similar/same main jet.