Bikes I have owned:
02 Kawasaki Ninja 250 (Parallel Twin 250)
My first bike. Forgave all my newbie mistakes. Never went down while I was riding. Traded it after ~10k miles in 5 months or so for my second bike.
93 Kawasaki ZX6E (I4 600)
Put 50k on this bike, 2 new engines (both blew at or around trackdays), rode it for 1.5 years. Eventually parted it out after the 2nd blown engine.
02 Suzuki SV650 (V-Twin 650)
Put 5k on this bike, bought it heavily modded with 135k on it. At 140k, the transmission fragged, I parted it out.
02 Honda CBR929RR (I4 929)
Bought for a song as a "high mileage" bike (33k). Rode it problem free for another 17k, sold it right before it hit 50k for the same amount I bought it for. Sold it because I got a shitload of tickets on it, my first literbike and way too easy to ride fast.
98 Triumph Daytona/Speed Triple (I3 955)
Replacement for the 929. Bought it faired, stripped the fairings and converted it to a streetfighter. Lost money hand over fist on it, put about 10k miles on it, probably the worst single motorcycle purchase I've ever made. Fun bike but plagued with fueling issues.
82 Honda XR500 (500cc Single)
My first dirt bike. Only put a little bit of mileage on it. Never sorted out carb issues, sold it shortly after I bought it for the same price I bought it for.
83 Honda Silverwing (500cc Transverse twin)
Free bike from a friend. It got to me only sorta running. I fixed the issues with it, put some mileage on it. Fun bike with a lot of personality, slow, shitty suspension, and very much a cruiser, but a lot of fun to tear around on. Sold after I got it running relatively reliably, recently saw it cruising down the freeway on a trailer.
02 Suzuki SV650 (Street)
00 Suzuki SV650 (Race)
These 2 SVs swapped engines, frames, parts, and just about everything else as a result of one bike being my fiancee's street bike, being involved in an accident, getting total lossed due to a cracked frame. I swapped all the race kit over to the totalled frame, had the frame rewelded, and raced it, and streeted the other SV for awhile. Eventually ended up parting out both bikes when I realized racing wasn't going to be happening in 2010. Made money on both of them between the fiancee's insurance payout and parting the bikes out.
Polini Pocketbike (Water cooled 80cc 2 stroke single)
Bar none, the most terrifying motorcycle I have ever ridden. 10hp in an ultralight package, no suspension, I couldn't turn it because my knees hit my elbows, brakes that were hugely ineffective. Sold for what I paid for it.
02 Kawasaki ZZR1200 (I4)
Rode it for about 8k. Good bike, just not for me. Sold to a friend from canada, he rode down and picked it up.
06 Kawasaki ZX636R (I4)
Bought as a project, fixed and sold. Ended up losing money on it, but I enjoyed the hell out of it and it strongly reminded me why I cannot have a supersport for street use, far too easy to go fast. Hit stupid speeds on it all the goddamn time.
94 Honda F2 (600cc I4)
Project from a friend, bought, fixed, and sold.
02 Kawasaki ZX9R (900cc I4)
Current project.
01 Suzuki DRZ400S-SM (400cc single)
Probably my favorite bike. Stupid light, enough power to have fun but not enough to get you into serious legal trouble. Heavily modded from when I bought it. Encourages all sorts of retarded behavior, wheelies, stoppies, takes a beating and keeps going, bulletproof engines. Very fast in the corners and very forgiving.
03 Suzuki DRZ440E-SM (overbored 440 single)
Pretty much the most modded DRZ I've ever seen, big bore kit, cams, carb, desert tank, plus a shitload of other stuff.
16 bikes, 6 years. I've slowed down over the last year, averaged 3 bikes a year for the first 5 years.