Rejetting?

My 81 Kz750 E has an air box in it. I want to switch to say K&N slip on filters individually for each carb,the question I have is will I have to rejet because of increased air flow?

Yes and good luck You will need a jet kit. Pod filters are very finicky. If you have not tuned carbs before you are in for a real treat. I am doing same thing as we speak Ive taken my carbs off 6 times. I am getting close. If your a machanic you should have know troubles. But my suggestion is leave it. Unless you are a very patient person Good luck

Yes you will need to re jet.

Is your exhaust the original 4 ->2 ?

When I bought my bike (1980 750 E1) 8 years ago it had a 4->1 Exhaust and K&N pods on it.

I eventually found that the best jetting was to have the secondary main at 140 (stock 125) and the primary main at 70 (stock 62 I think). Air mixture screws 2 turns out. If you have the 4->2 then you should try a tad lower jet numbers.

Last summer looking for a more stock look I put an airbox on it and jetted down. Much better at lower speeds.

Pods look cool, are good at higher speeds if you jet right but they dont like getting caught in the rain.

Keihin Jets are available from Z1Enterprises.

Good Luck

IowaKzfan wrote:

My 81 Kz750 E has an air box in it. I want to switch to say K&N slip on filters individually for each carb,the question I have is will I have to rejet because of increased air flow?

Don't do it !!

Do some searching under "pods" and "jetting" and you will archive a years worth of reading. After your new education on pods, you will hopefully decide to keep your stock airbox.

IowaKzfan wrote:

My 81 Kz750 E has an air box in it. I want to switch to say K&N slip on filters individually for each carb,the question I have is will I have to rejet because of increased air flow?

Absolutely, yes.

Remember, pods are for people who want to utilize the high rpm band power of an engine - mostly racing. Also - its not the kind of power boost your thinking - not much difference really till you on the highway/at high speeds.

Rejetting to make pods usable at lower rpms requires the installation of a proper kit, especially for those without experience.

You can put them on, but it will take many hours of tuning to make them usable/more power than your stock air box at low rpm. Mid and high rpm especially will benefit, but only with the correct setup.

Best of luck.

I am not a mechanic,and so...with all that I am hearing in the negative aspect,I think I will just keep using the air box filters. Thanks for all the input to everyone out there.