In the mid-1990s, after owning a string of Yammie RX100s and RD350s, I plumped for a KB125. The thing about this bike was it’s chassis. It was certainly better than that of any other 100cc/125cc stroker. That, plus the reasonably firm front suspension meant that you could really lay the bike down in turns.
You could approach a faaa....aaast sweeping bend in fourth, brake hard and late (brakes not very good, but not very bad either...), shift down two cogs, and power out of the corner really hard. You could, if you were so inclined, scrape the pegs without the rear end threatening to step out, or the front end threatening to wash out. Not bad at all.
Cornering speeds would be consistently higher than Yammie RX100s and/or Suzook 100s. The Honda CD 100s (and all their multiple variations) were, of course, blown into the weeds every time.
The engine was not as free-revving as that of the Shogun or the RX100, though the KB would still wheelie in second if you were up for that kind of a thing. The 125 Kaw mill never really had the guts, the fire, of the RX’s 100cc lump.
In races, it used to be up to the rider. The Yammie RX and the Shogun used to have the engines, the Kaw had the chassis. You could win on the Kaw, but you had to push harder than the others. Bravery would get you podium.
The clutch would take a lot of abuse without complaining, but the gearbox was not so good. It would crunch and grunch and make all sorts of noises if you gave it a hard time. The electricals were good. Mileage used to be about 35km/litre.
The bike was reasonably high-maintenance. Frequent visits to the dealer. But then my bikes used to be raced, and generally thrashed mercilessly. If you wanted hi-speed thrills, RX100s and Shoguns still ruled the roost. If only Bajaj had come out with the 250cc twin-cylinder two-stroke engine for this chassis, with a monoshock rear and a front disc-brake, this would’ve been the ultimate hoot...