Baby Ninja 250
After a 14 year break from riding, I picked this up last summer to use as 'cheap' commuter toy. I began amassing parts, and recently went through the forks, upgraded the rear shock, s/s brake lines & grabby pads, Metzeler tires, etc... It went from handling 'OK' to nearly excellent. Luckily there aren't a whole lot of other mods that can be done to these bikes without slinging buckets of dollars at an engine builder ...mainly just a 2:1 pipe, pod filters, and rejetting the carbs...and the 'gain' from those parts is more from weight loss than from a HP boost.
Mine is a 2004 model, but these are essentially unchanged since 1989, so spare parts are cheap & easy to get. Once I get this one where I want it, I might pick up another one and set it up pretty much identically, but strip the lights & street junk off to use for 'track days.'
Other bikes I've had over the years:
1974 Honda XR75
1976 KTM/Penton 400 Enduro
1976 Can-Am 175 Qualifier (1st bike with a street tag & insurance)
1982 Kawi KZ-1000J
1985 KTM 350 MXC (1st "new" bike)
1987 Harley 1100 Sportster (2nd "new" bike)
1973 Harley 1000 Sportster rigid-frame 'chopper'