For me 88 RM 250J 
would love another one 
i raced it in MX and enduros best modern bike i ever owned 
88 and 89 KXs were good to but everything fell to bits on them or wore out even when you were at work thinking about riding them 
Every thread stripped in the subframe the 2nd time you removed the side covers , the bearing in the bottom of the crankcase for the clutch actuator broke up , the factory must have coated the cylinder with teflon before the nickasil because the nickasil peeled off quicker than a $10.00 hookers knickers and many other things . They were great bikes but very expensive to maintain i sold the 89 (read gave away )and rode my 88 rm again rather than take out another morgage
85 CR 500 another personal favorite , dont know how different the 86,87,89 CRs are but the 85 was a rocketship my first open classer , caused a bowel evacution every time i rode it
Your riding style back then must have been even more ... unconventional... than it is now Bill.
Most other people talk of how poorly made that era Suzukis are.
The inserts in the KX subframe only seem to f$&k out when halfwits put in too-long bolts, or over-tighten them.
The other advantage is the similarity with the KX500s meaning that most bits are easy to get.
'87 CR250 is also a fantastic bike. Shame about the water-pump corrosion issues...
'88 YZ250 was way behind the others due to an unimpressive power delivery.
The '89 had a better motor, but is blighted by those early USDs.
