Getting My Hands Dirty with the KZ 400
So, I decided to pick up an old Kawasaki KZ 400 a while back. Wasn’t looking for anything fancy, just something simple to tinker with. Found one that looked like it had seen better days, but the price was right, you know? The guy said it ‘ran when parked’, which always makes you wonder.
First thing I did was get it back to my garage. Gave it a good look over. Yeah, it was rough. Dust everywhere, some rust spots, tires looked ancient. Tried turning it over, just got a weak click. Classic dead battery situation. No big surprise there.
Got a new battery hooked up. Okay, now it turned over, but wouldn’t fire up. Smelled like old gas. So, next step, drain that nasty old fuel. Tank had a bit of gunk inside too, so I spent some time cleaning that out best I could. Pulled the petcock, cleaned the filter screen. Still no joy.
Diving Deeper: Carbs and Sparks
Alright, time for the carbs. Knew this was coming. Pulled them off the bike, which was a bit fiddly. Took them apart on the bench. Man, they were gummed up bad. The jets were clogged solid. Spent a good afternoon carefully cleaning every little passage and jet with carb cleaner and some fine wire. Put it all back together, double-checking the float heights.
While I had things apart, I checked the basics:
- Changed the oil and filter. The old oil was black as night.
- Pulled the spark plugs. They looked okay, but I cleaned them and checked the gap anyway.
- Checked for spark. Actually had a decent blue spark on both sides, so the coils seemed alright for now.
Got the carbs back on, hooked up the fuel line with some fresh gas. Held my breath and hit the starter. It sputtered! Coughed a bit… then it roared to life! That sound was pure gold after all the work. Let it warm up, adjusted the idle screw a bit. Seemed to run okay, maybe a little rough, but running!
Riding the Old Twin
After checking the brakes (bled them and checked pad life) and putting some air in the old tires (replaced them soon after, don’t worry), I took it for a first proper ride around the block. It felt… well, like an old bike! Vibrates a bit, suspension is kinda basic, but it pulled okay. Definitely not a speed demon, but it gets up to speed just fine for cruising around town. That twin engine has a nice simple feel to it.
Been riding it on and off since then. It’s surprisingly good on gas, hardly uses any fuel, which is great. Can definitely keep up with traffic without any problems. It’s light enough to handle easily, feels really nimble actually. Simple bike, simple pleasures.
Had a few hiccups along the way, of course. Some electrical gremlins popped up – a dodgy connection here and there, blew a fuse once for no clear reason. But overall, it’s been pretty reliable for what it is. Parts are still findable if you look around a bit. It’s a straightforward machine, easy to work on mostly. No computers, no complex stuff, just basic mechanics.
Working on this KZ 400 taught me a lot. Patience, mostly! But also the satisfaction of bringing an old machine back to life with your own hands. It’s a cool little bike with character. Not perfect, but it’s got soul. Definitely a fun project and a decent ride.
