Finding the Craigslist Motorcycle
Okay, so I bought this busted Kawasaki triple last month off some dude on Marketplace. Guy swore up and down it “just needs a tune-up.” Riiight. Got it home, fired it up – sounded like a blender full of bolts. Knew the crank seals were toast. Typical two-stroke nightmare. Figured since I had to split the cases anyway… why not go big? Saw some old forum threads whispering about 1000cc two-stroke monsters. Sounded like pure madness. Had to try it.
The “Budget” Big Bore Plan
Didn’t wanna drop $5k on custom cylinders. Got sneaky instead. Found three worn-out Yamaha RD400 cylinders cheap, like $20 bucks each. Scrapyard treasures. Idea was simple: bore the heck outta these suckers way beyond spec and weld them together for the Kawasaki bottom end. People said it would vibrate apart or melt pistons. Challenge accepted.
Machining Mayhem
Took the RD jugs to my buddy Ray’s garage shop. His lathe is older than me. We clamped those cylinders down and just started grinding metal. Sweat dripping, chips flying everywhere.
- Massive boring: Went past the “max overbore” warnings. Like, WAY past. Pistons ended up almost coffee-can sized. Seriously scary thin cylinder walls left.
- Cutting ports bigger: Took the Dremel to the intake and exhaust ports. Opened them up like crazy. Exhaust port is practically window-sized now. Forget port “timing,” this was brute force.
- Welding insanity: Getting three cylinders perfectly aligned? Lol. Used about a mile of aluminum welding rod. Ground it smooth-ish. Looks gnarly as hell.
Reassembly & Terror
Getting the Frankenstein cylinders onto the Kawasaki cases was like wrestling an octopus. Forgot which stud went where twice. Used every gasket sealer in the shop. Had to hammer the pistons onto the rods because the wrist pins were stupid tight. Fuel lines hooked up to leaky aftermarket carbs I found buried under a bench. Poured in my sketchy homebrew race gas – smells like paint thinner and bad decisions.
The Moment of Truth
Kicked it over. Nothing. Cursed. Kicked harder. Backfired like a cannon. Scared the dog halfway down the street. One more kick… AND IT ROARED. Loud doesn’t cover it. This thing shrieks. Idle shakes the whole workbench. Blip the throttle? The front wheel just lifts. Just sitting there. On the stand. Didn’t even mean to. The torque is savage, instant. Feels like the whole bike wants to twist itself inside out. Smoke? Oh yeah, enough blue fog to kill every mosquito in the county. It’s leaking fuel somewhere. Vibrations make my hands numb. It’s terrifying. It’s ridiculous. It absolutely rips.
The “Secrets”? Just Grunt Work
Forget fancy theories. This was sweat, cheap parts, and maybe too many energy drinks. Big holes move more fuel and air. Giant ports dump burnt junk out faster. It runs pig-rich and vibrates like crazy… but the grunt when it hooks up? Unreal. Powerband hits like a sledgehammer. Zero finesse. Pure, stupid, glorious violence. Would I ride this down the highway? Hell no. But for making insane noise and scaring neighbors? Perfect 10/10. Next step? Maybe wheelie bars…
