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/128166
2003 Yamaha YZ125 for '02 will be enough to hold them over for '03. It'll be close. Despite taking on numerous and fairly significant changes for '02, the YZl25 didn't dominate the magazine shootouts as it had in previous years, but all was not lost for Yamaha, as it was still regarded by all of the motomags as being one of the best 125cc production MXers out there. (After ruling the 125cc class for many years, the YZ finished a lowly second to the Suzuki RM 125 in our '02 125cc MX shootout.) Even though the YZ 125 did come out on top of other magazine shootouts, it's hard not to deny that the YZ 125 is beginning to show signs of losing its throttlehold on the highly competitive 125cc- The VZ125 was knocked off the top step of our eN 125cc MX Shootout podium in '02, but an number of subtle changes to the '03 just might put It back on top. VAMAHA FINE-TUNES THE VZ125 By PHOTOS four-stroke YZFs. This year, the KIT PALMER By roles have been reversed, with Yamaha focusing almost all of its CHRIS JONNUM n ast year, Yamaha gave its twoL':J stroke attention on the all-new YZ450F line of YZ motocrossers a (and WR450F) and significantly fairly extensive makeover, while pretty much letting well enough updated YZ250F, all the while hoping that the extensive changes alone with the company's line of Yamaha made to the YZ two-strokes ENGINE • Combustion-chamber volume is changed from 10.2cc to I '. ~ lO.05cc • Exhaust-port shapes are changed (to enhance chamber volume change) • YPVS power-valve stopper modified for improved sealing • New carburetor features new settings and minor updates • Intake manifold is now straighter • Air cleaner joint is also changed and is the same as the . '02 VZ250 • Reed-valve thickness is .05mm thicker • First and second gear ratios are slighter taller CHASSIS • Frame's main-pipe thickness is changed from ll.6mm to ll.8mm • Frame's cross-pipe thickness is changed from l2.6mm to l2.3mm • Three weight-saving holes have been added to the main frame • The axle end of the swingarm is smaller and is hollowed to decrease weight • Swingarm features anodized treatment • The plastic rear-caliper protector is redesigned (smaller and lighter) • New and lighter seal guard (chain slider) • The front brake now uses an aluminum piston instead of plastic and is reshaped for easier air bleeding • Front master cylinder is changed slightly to reduce weight and provide easier separation of air from oil • New rear-brake caliper (brake-pad area Is changed and piston diameter is changed from 27mm to 25.4mm) • Rear master cylinder is all-new (reserve tank is int",grated with the master cylinder and piston diameter is changed from 12.7mm to 1 J.6mm) 'I' ." '. ~ ,'{f. ~«'t1i: ~!t:" ,-. £from che ~i Even though I don't really consider myself a "l25cc rider," I have always enjoyed riding the YZ125 because, of all of the 125s out there, it reminds me the most of the bigger bikes, with its powerful motor and broad-for-a-125 powerband. And I feel the same way about the '03 YZ. As I pretty much expected (and hoped), the '03 YZ feels much like last year's YZ. In fact, I was hard-pressed to feel any difference at all until Yamaha gave me the chance to spin a few laps on an '02 YZ for a quick back-toback comparison, where I could detect some improvement in the '03's motor. The new YZ seems to come alive a little quicker off the bottom and appears to have a bit more bulk right in the middle of the powerband, while power on top seems about the same. Basically, it's still a wellrounded motor, which I certainly appreciated on the rough Glen Helen track. There is, however, on", ar",a with the YZ that really stood out on the positive side, and that was carburetion. Our test bike came jetted spot on, even for the excessively hot conditions that day at Glen Helen. Who knows, maybe in more desirable weather conditions, the YZ might load up and die like an old CZ; I doubt it, but at least on this hot and steamy day, the yz ran crispy clean, which hasn't always been the case in years past with the YZ125. If you liked the suspension on last year's YZ, then you'll no doubt like the shock and fork on this year's YZ as well, since Yamaha made only minor adjustments to both ends. To be honest, I couldn't notice any difference at all, but I didn't have a problem with that, whatsoever. as 1had no real complaints with last year's plush-yet-brawny suspension. No sense tinkering with something that alr",ady works, I guess. In other areas, the YZ's brak",s ar", as strong and predictable as ever, the controls are light and easy to operat"" and the transmission meshes as smooth as silk - just like last year's YZ. Overall, there really isn't anything that the new yz lacks, except, perhaps, airconditioning. The triple-digit temperatures that day at Glen Helen cut short our flTSt ride on the little YZ, but we've got a lot more track time planned for it in the future. But, for now, I can safely say that the new YZ is another shootout-winning contender - big changes or not. KIt Palm." 38 AUGUST 7, 2002' cue I • n • _ s