Thinking about getting VM34/6, need info

I currently have a 1979 KZ1000 with a bored engine (sad issue is I'm not sure the size of the bore, the idiots who rebuilt my engine left me the dark about a few things) I believe it is at least around 1100cc's now as supposedly when I got the bike it was 1075cc or so and then when I had to get it rebuilt it was bored again.

I currently have VM29 smoothbores and a gravity fed petcock (the standard one) I have K&N oval pods (not sure if this is prudent information or not).

So I suppose my questions are as follows:

1. Which of the two is probably better for the bike; the VM34's or the VM36's?
2. What am I going to need to consider other than question 1, and just simply getting the set? Such as, it is guaranteed that I will need to intake manifolds and clamps etc.?
3. Is there any reason to avoid them or any general voices of concern or suggestion in regards to carbs for a bored KZ1000?


This is the little bit of info I am working with so far: www.redlinecycle.com/VM34-36%20Conversion.html

Thanks in advance!

Limitlesstruth wrote: I currently have a 1979 KZ1000 with a bored engine (sad issue is I'm not sure the size of the bore, the idiots who rebuilt my engine left me the dark about a few things) I believe it is at least around 1100cc's now as supposedly when I got the bike it was 1075cc or so and then when I had to get it rebuilt it was bored again.

I currently have VM29 smoothbores and a gravity fed petcock (the standard one) I have K&N oval pods (not sure if this is prudent information or not).

So I suppose my questions are as follows:

1. Which of the two is probably better for the bike; the VM34's or the VM36's?
2. What am I going to need to consider other than question 1, and just simply getting the set? Such as, it is guaranteed that I will need to intake manifolds and clamps etc.?
3. Is there any reason to avoid them or any general voices of concern or suggestion in regards to carbs for a bored KZ1000?


This is the little bit of info I am working with so far: www.redlinecycle.com/VM34-36%20Conversion.html

Thanks in advance!

I think you should learn more about your engine and read all the information on that web page.

I've read over the page, I was hoping for some elaboration on the information given.

It says that petcock replacement is recommended but not always necessary, also that the vm36 is meant for bikes "1135cc engines and larger with more radical cams and head work". What does this mean exactly? That it will be no different than vm34s or that it won't really work unless the engine is bored out that far and has higher end cams and such?

Also I have a wisco bore kit, that is all the guys who rebuilt my engine let on, I suppose I can contact them and inquire about more info...

I guess I'll just completely repost this question later when I have more information and I am closer to actually making the purchase or just talk to the guy at Redline about it.

Are you referring to the Mikuni RS34 and RS36 carbs? If so the 36 flows more air at full throttle but gives up some power down low. The 34's will be better suited for your engine if all you have done to it is a larger bore. Why not run the VM29's and save yourself some money. If you really want the modern carbs I would go with the RS34. They will probably be set up correctly right out of the box. You are going to need the larger intake manifolds from the later 1000J engine or the GPz1100.

With just a 1075 or 1100 kit the VM34's or VM36's will be too big.
You will need major head work and cams at least to need anything near that size.
I have vm32mm smoothies with high comp 1100cc, manzano race head, o's stainless valves, race cams and the VM32's are plenty big enough ( 170mph big enough )in fact there's no real difference to the 26's i bored out to 30mm i had fitted previous.
You want the smallest carb possible matched to your engine spec to keep good throttle response and smooth running throughout the rev range.
Just fitting big carbs won't make your bike faster but will ruin your bottom end throttle response and fueling.
Go spend your money on some head work and street cams.

There we go, responses that mean something more.

I've just been looking over different parts and different custom bikes and took a notice of them without much knowledge, I suppose I will just save myself that money and put it elsewhere on the bike as Zed has suggested.

If down the road I have a more built up engine at least I'll know that if I did decide to get new carbs that the Mikuni VM34rs carbs are probably the way to go.

I still need to look into higher output coils I believe, or at least would like to.

Thanks for the information and everything!

Dyna coils (green 3ohm for points models) are good and produce more voltage than the std ones.
However if you are on points it's hardly worth fitting them without DYNA 'S' pick-ups too.
Fit the whole package and you'll have sparks like an arc welder that will light a bucket of piss.

The point Zed1015 made about wanting the smallest carbs for that build of engine is key. Larger is not better when it comes to carbs. You need a MATCHED set of components to get the best out of the bike. RS34's are really for 1200cc engines or bigger. You can make them work on smaller engines, and while you gain good top-end performance, you lose on the throttle response in the rev range you typically ride in.

I would assume 1075cc is the bore on your bike. If that is the case, the VM29's are the best choice - even with a flowed head and moderate lift cams.

"VM34RS are recommended for smaller bore engines and specific applications up to 1197cc"

That is from the website I listed whose information I was working with; he says its "UP TO 1197cc".

Your guess is just about as good as mine, I'm working under the assumption of 1105cc cause it was supposedly bored when I bought it then bored again when I had to rebuild the engine cause the head was cracked. However I'm working on such little information about it that I'm not sure if both were actually done. I'm planning on sticking with the VM29s for now. I don't ever use the full power of the bike or even go for rides of much length either.

Thanks for the reply though.