Heh. I was the one that steered Atek3 towards the SV. Glad to see that's working out.
OK. Going as far back as 1988 or so, there's been two bikes that are stable, "fast enough" to at least start with, don't have any bad handling habits and go like gangbusters. The Suzuki GS500 parallel twin and the Kawi EX500.
Kawi updated the EX500 slightly over the years - later models with the 17" front rim are more desirable, and that's what you're looking at.
The EX has one flaw: the engine is a nice high-tech four-valve-per-cylinder mill, watercooled, basically the old Ninja 1000 motor "sawn in half" (and even shares some valvetrain/piston/rod parts I think?) BUT they need a valve adjustment every 5,000 - 6,000 miles if I recall right. And unfortunately it's a nasty shim-and-bucket setup that's difficult to do yourself. It'll probably run a couple hundred each time.
The GS500 had a two-valve-per-cyliner setup with screw-adjust valves. They needed looking at every 3,000 or so miles but were an easy home job.
Suzuki basically never changed the GS500 from '88 to 2004. I kid you not, other than paint and minor cosmetic stuff, same bike. If you're on a budget these are a GREAT way to start.
The SV650 is Suzuki's more modern replacement for the old GS in the same role - sporty but with smooth stable handling and power that hits in a controllable fashion.
See...the more cylinders you have, the more power you'll get for the same displacement. A one-cylinder 600 will have less than a third the power of a four-cylinder 600. The problem with most of the four-bangers is that the power hits "only at the top end" and comes on all of a sudden...you'll gas it in mid corner, it'll come on calm enough up through about 8,000rpm at which point all hell breaks loose, horsepower doubles, it spits you into the next county unless you're ready for it.
A twin is a nice split between the two...some decent but not explosive top end.
Upshot: the GS500 is one of the cheapest bikes to keep rolling if you do your own modest wrenching. The EX500 is more complex for the home wrench and you'll need help with those valves probably...but other than that they're damned fine.
I don't remember what the valve adjust system for the SV650 is...Atek3, are they screw-adjust, shims or hydraulic self-adjusting?
My current ride: '97 Buell S3 Thunderbolt, flattracker bars off a dirtbike, PM aluminum rims, 1250-kit Axtell nickle-silicon ceramic lined barrels, matching 10.5:1 forged race pistons with dome pattern based on the Thunderstorm heads, 2004-model heads with oversize valves and cut for Thunderstorm pistons, Mikuni HS42 carb and the last piece is waiting in storage for install next week...a KT Engineering out-of-production race pipe, the final bit I need to get up over 100hp at the crank out of this hopped-up Harley Sportster mill
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