mechanic says pod filters won't work? help anyone?

So I finally ended up bringing my 1980 kz440A1 into a mechanic to get the carbs done up. Turns out that the overflow tube was cracked in one of the bowls so that was a good move. The only problem was that I couldn't for the longest time find an airbox for the bike, so I bought 2 k&n pods to go on instead.

When I came back to pick up the bike, the mechanic told me that the pods will continually give me dead spots, which they are, but I can't tell if he just jetted them wrong. He didn't tell me what he put in there for the main or pilot so I'm in the dark.

I just don't get it, other folks have done the same thing and not had this problem. What should I do? find an airbox (nearly impossible to get all the parts).

Would like to hear an answer to this too. I did see a full airbox assembly on ebay yesterday or the day before, but it was 50 bucks buy it now with 25 for shipping

I dont mind making a work around for now, but like you would like some kind of perm solution that would look good.

I'm aware of the problem finding a stock KZ440 air box. It looks like it has vanished from a lot of bikes. I believe your mechanic is right though. I'm pretty shure he has tuned it the best that he can with the set up you have. There is more to it than just the increase in the air flow when you convert to pod filters with the CV carbs. It is possible to get the air/ fuel mixture pretty good by altering jet sizes and shimming the jet needles, but you also disturb the vacum and the air flow that is controlling the slides by putting on pod filters. That is the reason for the flat spots. And that is next to impossible to correct. An old Kawasaki mechanic I know told me that he had experienced that vacum slides sometimes hardly moves at all when you put on pod filters on CV carbs.
On ordinary piston carbs where the slides are controlled by the trottle grip, this won't be a problem.

I have been experimenting with different air filters on my KZ400 with CV carbs, and I have found that the best is to keep the stock air box. And if you wan't to increase the air flow, it is best done by using a filter element that flows more air in the stock filter box. The only downside with the stock filter box is that it makes it more difficult to remove and install the carbs. Otherwise, it is the better option as I see it.

Hey Ibby, good to hear from ya!

I agree, pods cause a lot of headaches on these CV carbs. I was pretty successful on a 1976 400 with pods, but it was a pain. The air jets, main jets, and idle jets had to be altered.

The details won't help on the 440 since the carbs are different. I assume the 440 uses rubber-diaphragm/spring-return type CV. The earlier ones were rigid-piston/gravity-return.

this wouldnt be related to the old what-were-they emgo pods that blocked off (partially?) the ports for the vacuum slide, would it?

Rickman wrote:

this wouldnt be related to the old what-were-they emgo pods that blocked off (partially?) the ports for the vacuum slide, would it?

That is also a possibilty and a stated problem, but I don't think the K&N filters have got that problem though.

Rickman wrote:

this wouldnt be related to the old what-were-they emgo pods that blocked off (partially?) the ports for the vacuum slide, would it?

good catch. another thread brought up this problem awhile back with the emgo filters. the rubber partially blocked the openings. even posted pics to illustrate.

Open them up and see what jets you have in there, see if your mechanic shimmed the needles.

My buddy recently inquired about K&N pods for his 750 at a Kawasaki dealership. The guy behind the counter actually told him, get this, "Pod filters are only used on race bikes." I had to laugh like hell!

I have K&N pods and a Kerker 4 into 1. The only flat spot I have is a little off-idle stumble. I could probably tune it out but I don't care, I'm used to it.



Post edited by: guitargeek, at: 2006/09/02 22:07

So that's the answer to pods then? Rejet the carb, and you're 'probably' fine?

pyxen wrote:

So that's the answer to pods then? Rejet the carb, and you're 'probably' fine?

yes, carbs are jetted from factory to work with the amount of air flow an air box will give them, if you use pods, increasing the air flow, the carbs need to be adjusted by jetting them to the new amount of air flow to maintain the correct air/fuel mixture.

The other option is to cut strips of tin or aluminum to partially cover the filter on your pods. You would attach the strips with zip ties. This will restrict the flow a bit and give you the same or similar charcteristics as having an airbox. I have done this on a half a dozen bikes and it does work. You may have to cover as much as half of the filter surface area for it to work the best. This will get you around pretty good until you locate a stock airbox.

del