'80 KZ650F Jetting question

Hi all,

I have a bone stock '80 KZ650F that I'm looking at putting pods on (after pulling the carbs off the stock airbox 3 times, I've had enough). It has pumper carbs, non-adjustable needles, 15 idle jets, and 97.5 main jets. Considering I'll have the stock exhaust on and that the 97.5s are already tending toward lean, would 102 mains be about right? What size idle jet would I want to try first?

firehawk400 wrote:

Hi all,

I have a bone stock '80 KZ650F that I'm looking at putting pods on (after pulling the carbs off the stock airbox 3 times, I've had enough). It has pumper carbs, non-adjustable needles, 15 idle jets, and 97.5 main jets. Considering I'll have the stock exhaust on and that the 97.5s are already tending toward lean, would 102 mains be about right? What size idle jet would I want to try first?

Hello, Scott, and WELCOME to KZR!
We're glad you're here!

R&R carbs easy as pie with new airbox hoses, cheaper than pods, and none of the headaches.

Click> www.z1enterprises.com/detail.aspx?ID=331

And BTW, would hold onto the airbox, just in case. :lol:

Good Fortune!

Yes, get the new airbox ducts. Might be less trouble too.

firehawk400 wrote:

Hi all,

I have a bone stock '80 KZ650F that I'm looking at putting pods on (after pulling the carbs off the stock airbox 3 times, I've had enough). It has pumper carbs, non-adjustable needles, 15 idle jets, and 97.5 main jets. Considering I'll have the stock exhaust on and that the 97.5s are already tending toward lean, would 102 mains be about right? What size idle jet would I want to try first?

I agree with the above answers but to address your question... 102.5 was the "standard" jetting for most all pre-EPA 650's. Even with stock exhaust I would think you would want at least 105's, if not more with pods. A lot of guys here run pods with great success but they can be a major PITA to jet properly. Plus you need to consider water (rain, washing bike, etc) plus other factors associated with running pods. So, are you having a problem with your carbs? :huh:

My carbs are working perfectly, I just want to be rid of the stock airbox - pain in the butt to get carbs on and off, and its restrictive.

I know my way around carbs pretty well, and I'm not afraid to mess with jetting. Some jetting headaches are more than worth the trouble if I don't have to work around that airbox anymore.

My main source for parts (bikebandit.com) can get me 102.5s or 105R's (racing use evidently...not sure what difference that makes, if any). What exactly does that R suffix mean? If those are unsuitable, where would be a good source for jets?

On a different note, since I have non-adjustable needles and pilot jets seem to be hard to come by (and I really don't want to drop a ton of money on this since I also have a top end rebuild in progress) would it be better to suck it up and stay with the airbox?

I believe the R mean round (or maybe large round).
Z1Enterprises.com has the jets & other stuff for your bike.
The customer service there is top notch: if you aren't sure of something, call or email.

Sometimes when searching for stuff there, you have to be aware of your spelling & whether or not the part might be listed in singular or plural. I.e., a search for clutch cables may not yield any results, but clutch cable will. Searching for Main Jet will show 3-4 pages of jets ; Main Jets will only show the Keihins.