1978 KZ200 how to jett the carb, k&n filter

Hey guys im new and have "little" mechanical knowledge so go easy. I just bought a 1978 KZ200 for 500 bucks. The bike started so i rhode it home but it died on me twice. The spark plug was getting fouled up and i had to dry it and keep trying to kick start it since either the battery is dead or starting system is done. When i try to start it now after replacing the old plug it starts but it takes some time. I want to change the filter to a metal k n filter but i heard i have to jet the carb does anyone know about either how to "jet" the carb? or a k n filter that will fit on this carb?

Do yourself a huge favor and perform a a full tuneup on the bike before changing the type of air filter, jets, or making any other mods. Also, get a manual and learn as much as possible about your bike before tinkering with it. When you try to start it with the engine cold you should turn the fuel and choke on and do not touch the throttle at all. If it does not start and run well, you need to do (or have someone do) a full tuneup including points/condenser; plug; check valve clearances; clean carb if needed; change oil & filter; etc. Do all that and get everything within factory spec and the bike should start and run very well. At that point you can monkey with changing filter types etc. and you will be able to compare post-mod performance to stock performance to see if you want to undo or redo the mods. Trying to rejet a bike that is not otherwise properly tuned up is a major waste of time, energy, and money because rejetting a carb is never going to compensate for pitted points, bad condenser, too tight valve clearances, etc. Ed

I got the service manual. Been reading it periodically. Going to read about the valve clearances and so forth. What is the condenser and pitted points? thanks ed.

Check the section in your manual regarding ignition timing and points. If they and the condenser have not been changed recently they need to be. They points get pitted over time, and the condensers can fail, and either problem will definitely make the bike run poorly. Ed