1983 KZ650 Carbs.

Ok I'm editing this so that it makes better sense :whistle:

Heres the deal: 1983 KZ650 CSR, stock carburators, stock jetting, stock airbox, stock airfilter, 4-1 kerker exhaust.

What kind of carb is stock? VM24's?
What style jets should I use?
Where can I buy said jets?
Does anyone have a recommendation for a starting point with jetting?

I live in Michigan, so I think the elevation here is pretty normal (low) for the US.

Post edited by: newbikekiller, at: 2006/03/13 22:54

Post edited by: newbikekiller, at: 2006/03/13 22:57

Post edited by: newbikekiller, at: 2006/03/13 22:59

See, I eventually answer. Give me a chance. This is my work busy season and answering questions on the board has to take a back seat to my work right now. Be patient with me. I need to eat and the cash customers are the ones who feed me! bwhahaha

Ok I'm editing this so that it makes better sense

---by golly, we are OK with this so far...



Heres the deal: 1983 KZ650 CSR, stock carburators, stock jetting, stock airbox, stock airfilter, 4-1 kerker exhaust.

---OK so far....



What kind of carb is stock? VM24's?

---Mikuni BS32 carbs are stock. A Kaw Factory Service Manual or Clymers for your model will tell you this...

What style jets should I use?

---Style? The same style as are in there now. The main jets are the same for most all Mikuni carbs and you have a BS series pilot jets... I don't recall the series number but it is like BS34/90 or something.

Where can I buy said jets?

----www.z1enterprises.com - Tell Jeff you have BS32 carbs; he will know what pilots you have.

Does anyone have a recommendation for a starting point with jetting?

----Yeah, stock jets will be fine... you might want to go up a size. Look up your stock jet sizes in the manual I have already suggested.


I live in Michigan, so I think the elevation here is pretty normal (low) for the US.

----see jetting suggestion... altitude won't be a factor

Man Thanks A TON WG!

OK - now for a four more silly begginner questions (I've never dealt with jetting before)

1.) Which jets may need to be adjusted? (Main/Pilot/jet needle - or all?). I just wanna make sure I have all the necessary parts on hand before I start... I don't mind paying a little more and ending up with too many jets at hand.

2.) I understand that the jet needle on my bike is not the "adjustable type". But I also understand that I can probably get away with shimming the jet needle to tune it. That being said, is there any chance that I would need a different jet needle, or should shimming do the trick?

3.) What size shims should I use?

4.) Where may I get said shims?

You don't much need to rejet. Try running the bike as-is and see how it feels to you. The pilot circuit/midrange should be OK and these are governed by the pilot jet and jet needle/needle jet respectively. Once you hit about 7-8K rpm, you may feel sluggish with the pipe. If you do, you may need to go up ONE SIZE main jet. Look at what is stamped on one of your main jets and adjust accordingly. You don't need to "shim". I think that if you are not familiar with carburetors to go slow with making mods. MOST performance related issues can be solved by making sure the bike is tuned up and the electrical system is working as it should. Many folks jump on carburetion too quickly when trying to fix problems or perceived problems. The stock airbox and 4 into 1 Kerker which likely has baffles shouldn't need much tweeking from a jetting standpoint.