Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/127803
RIDING ·IMPRESSION 1997 Suzuki RM125V By Kit Palmer Photos by Kinney Jones ou· might say that Suzuki has taken a little bit of the fun out of buying a new bike. Roll up to the starting line on the new 1997 Suzuki RM125 and hardly anyone will notice that you're atop one of the latest 125cc motocrossers to roll off the assembly line. A close examination of the yellow, I black and purple machine will leave even the most meticulous observer hard-pressed to tell last year's ('96) RM125 apart from.the '97 RM125. Minor graphic changes are the only clues. However, if you had X-ray vision, you'd see that the '97 RM125 is, in fact, a changed motorcycle. Suzuki engineers are quick to point out the RM125's all-new cylinder. The old cylinder was basically scrapped for one that features completely different port timing, shapes and exhaust port routing. No longer does the cylinder incorporate exhaust sub-ports. A new cylinder head results in a high compression ratio at higher rpm and lower compression and lower rpm. Suzuki's AETC/PC (Automatic Exhaust Timing Control/Power Chamber) power-valve system, which made its RM125 debut last year, has been slightly modified as well. The power-valve stroke governor the rod that holds the valve open - has been lengthened. According to Suzuki, the valve didn't quite open fully at high rpm and would flutter ever so slightly, disrupting the exhaust flow. Now, according to Suzuki, the valve opens to maximum efficiency and remains that way with no movement for more consistent operation. (Top) Grab a handful of throttle on the 1997 Suzuki RMl25 and the front end won't hesitate to climb. There's plenty of paweron tap. (Above and left) Visually, there's not a bit of difference between the '97 and '96 .RMs. Suzuki also went with a 5mm shorter· connecting rod, which is claimed to increase crankcase compression, resulting in a quicker-revving motor. A new carburetor is also used. The Keihin PWK36 fuel/air mixer, which feeds a case-reed induction system, now feature fins, similar to the "bat wings" used in the Kawasaki MXers. The Suzuki's two fins, which are located inside the carburetor's air intake funnel, are said to improve intake air flow over the jet nozzle at small throttle settings, thus improving throttle response and enhancing bottom-end performance. Taking all these changes into account, it almost goes without saying that the exhaust pipe has been revised. It has been shortened at the cylinder connection area. Suzuki also changed the final gearin$ slightly by going up one tooth (50) on the rear sprocket. The 12-tooth cotintershaft sprocket was left alone. And what do all these changes mean? Suzuki claims that the new cylinder, refmed power-valve, shorter connecting rod, finned carb and new pipe combination add up to more power