KZ400 1979.Jetting after pod filters. Need advice

I put on new pod filter on my KZ400 1979. I put on 75 jets, i had 70 jets before, is this right jetting? need advice

How did the bike run before you replaced the airbox and filter with pods? If it was running well then you can go ahead and experiment with pod filters. If it was not running well then put the airbox back on and get everything tuned properly first, including valve adjustment, checking compression of each cylinder, timing, points adjusted and carbs dialed in. Make sure all that is good before moving on to experimenting with pods otherwise you don't know if the tuning issues you are running into are because of the carbs/pods or something else.

First off, what brand of pods. If they are cheap Emgo or generic pods then remove them. If you must use pods then use something like K&N or Uni.

I cannot tell you what jets are correct for your bike - too many variables. Only your bike can tell you what jetting it needs. Make sure carbs are synced, air/fuel mixture screws and idle are adjusted per the Factory service manual, if you don't have one you can find one online. Check out kz400.com. Once that is done you can check if your pilot jets are good by getting the bike warm, putting in a new set of plugs and letting it idle for a few minutes and then pull the plugs. Now read the plugs using one of the many diagrams of plugs you can find online. If they are too rich then you may need to lean out the air/fuel mixture screw some more or possibly even go to a smaller pilot jet. If they read too lean then richen the air/fuel mixture screws and/or go with bigger pilot jets. After you have the pilots dialed in then you can start working on the main jets. Tweak them by going up a jet size and testing performance and doing throttle chops and checking your plugs. Keep going up a size until performance drops and plugs are looking dark. Then go back down sizes until performance drops and plugs look lean. Pick the jet somewhere in between where performance seems best and plugs look the best.

diggerdanh wrote: How did the bike run before you replaced the airbox and filter with pods? If it was running well then you can go ahead and experiment with pod filters. If it was not running well then put the airbox back on and get everything tuned properly first, including valve adjustment, checking compression of each cylinder, timing, points adjusted and carbs dialed in. Make sure all that is good before moving on to experimenting with pods otherwise you don't know if the tuning issues you are running into are because of the carbs/pods or something else.

Do yourself a huge favor and follow diggerdanh's advice! Truer words were never spoken. Ed

Check out the link in my signature, bottom of page 12.
That will give you an idea of where to start. Now the DynoJet
jets are numbered differently. There are DynoJet jet size
conversion charts are all over the www.


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