Bogging down kz700

Needing some advice guys. So when I bought the bike (84 Kz700) i was able to get it running. It had a pods on it so I decided to keep them since I did not have stock air box. After riding I got sick of back firing from my exhaust. I also have mac 4 into 1. So I purchased a stock air box with a k and n filter. Bike idles even better. And starts a tad easier. But going down road I bog down around 5-6k rpm. And if I keep going I can kind of work out of it. I pulled carbs and I have a 165 main jet. Bike ran high rpm no oroblems with pods on. But now with stock box it does not. Any ideas on what main jet originally came on these carbs?

Thanks

I'd be interested to hear the answer to this

Your carbs should be the Mikuni BS34 and a 165 main jet is way to big for a 700. To put things into perspective here I have a modded Gpz 1100 and when it had BS34 the mains were 127.5.
I would check to make sure the carbs are either stock or have a jet kit. You can verify that by the needles if they are adjustable then it probably has a jet kit if not then they are stock. And by adjustable I mean slots on the needles to move the clip up or down.
If the carbs are stock I would go down to a 122.5 mains, 17.5 pilot jet and about 2 1/2 turns out on the mixture screws. If the carbs have a jet kit still put in the 122.5 main jets and 17.5 pilot jets with the needle clip in the middle slot. That should get you in the ballpark presuming your are using a 4 to 1 pipe and pod filters.

I completely ditched the pods. Got tired of them. Went to stock box with drop in k+n. The needle does have different settings. The dynojet kits comes with a 110 main 160 and 165. Since it has diffrrent needles should I try the 110 first? Thanks

Also. There are white deposits on my plugs which makes think its lean. Also have a back fire after letting off throttle.

Marklorenzo wrote: Also. There are white deposits on my plugs which makes think its lean. Also have a back fire after letting off throttle.

Decel pop is usually from a lean PILOT jet or a vacuum leak. Bogging at about 5K rpm on mine was caused by rich main jets.

Forget the jet kit jets they are sized differently than mikuni's. Use mikuni jets and start with 122.5 for the mains and 17.5 pilots. The popping you hear on decel is a to lean condition on the idle circuit. Before making any changes though I would insure you have no vacume leaks.

No vacuum leaks. Checked those. Brand new air box boots also. I will order new pilots and mains and test to What happens. Thanks

Did some research on jets. Looks like I cant even get low enough to that size Baldy on my pilot jets. PJMotorsports does not offer 27.5 pilots. Hmmmmmm