Cycle News - Archive Issues - 1990's

(Right) A new threestage power valve system, revised porting timing and combustion chamber designs, a new exhaust pipe, Ignition, and Kelhin PWK38 "finned" carb make up the bulk of the changes to the motor. (Below) A more progressive linkage ratio and a 3mm longer shock shaft round out the ~hanges to the rear end. with modified ignition .characteristics to compliment the other engine: changes. Suzuki didn't stop with the top end of the motor, and fiddled with one of last year's best tranny and clutch packages. The clutch has been upgraded with revised friction plates and new steel drive plates in an effort to reduce variations in clutch play, increase durability, and provide more consistent operation. To improve crankcase rigidity and help prevent costly chain-throwing-induced transmission failures, the sprocket cover no longer shares the same bolt-on attachment point as the crankcase. The chassis received two significant changes directed toward providing a better combin~tion of agility and stability. The rake angle was reduced (the front wheel came in) by 0.5 of a degree for enhanced agility through turns, while the frame down-tube diameter was increased from 25.4mm to 28.6mm for improved straight-line stability. Suspension-wise, Suzuki decided to alter its unanimously praised 49mm conventional twin-chamber cartridge fork. The fork's below-axle extension has been shortened by 20mm to reduce the chance .of dragging them in ruts and rocks. This was accomplished by reducing the wheelstroke (from 300mm to 290mm) and by using larger-volume cartridges (from 20mm x 10mm to 23m x 12mm). The larger-volume cartridges are also said to enhance the fork's smooth and progressive action and reduce harshness. The front hub has been beefed up to improve front-end rigidity and improve stability, especially when going over ruts and entering turns. Out back, the suspension has a modified lever cushion I rod cushion combination that 1Oeportedly delivers a more refined .leverage ratio, more progressive action, and increased rear damper stroke (from 135mm to 138mm). More suspension stroke was added for enhanced energy-absorbing capabilities and stability. Last year's RM250 motor was pretty good. It may already have been said enough, but the motor reminded us of a Honda - the same type of power of the CR, but just not quite as much. We still feel that way about it this year. It's got good, no, excellent power everywhere in powerband with immediate throttle response and seems to have picked up some bottom end, which is probably due to the new three-stage power-valve system and "finned" carbo Overall, the '97 RM has more usable power than before. Simply put, this bike roosts and feels like a CR motor more than ever. The on.ly thing we didn't like about the RM's powerplant was the amount of engine noise it emits. Even when spanking new, the motor already sounds as though it has a few races under its seat. But not to worry, as this has been an RM trait for a number of years now. The transmission and clutch are simply perfect. The transmission shifts smoothly and consistently every time even under a heav'y load (throttle pinned) with or without taking a stab at the dutch lever. The dutch takes abuse well and doesn't fade or get that vague feeling that last year's would sometimes exhibit under long periods of hard use or after it started to significantly wear. The forks on the RM250 work great for us in a wide variety of conditions ranging from big landings to small chop utilizing the standard suspension clicker settings. The only place the forks seemed to transmit a harsh feeling was at high speed over square-edge bumps (curbs). We do feel, however, that this probably could be alleviated with some more fine tuning on the suspension settings (clickers). Hopefully, we can adjust this trait out without affecting the great action everywhere else with some more setup time at the track. We were pleased with the action that the new shock linkage and longer shock (3mm at the shaft) produced in varied terrain. The shock exhibits a good resistance to bottoming and still handled the small stuff we.ll. We're still not totally at . ease with the back, though. It still has the tendency to kick on high-speed jumps with kicker bumps (or lips) at the top. You never quite know what the rear end is going to do in these situations. You do know that the rear end is (Right) Even larger riders will like the '97 RM250's layout It's easy to move around on. going to do something - either stay straight, kick up, to the left, or to the right - it's a complete mystery. The brakes on the RM are up to par with the rest of the class, offering good feel and excellent stopping power. 'Nuf said. It's very strange to us that the bike actua.lly handles better this year, with the rake coming in as it was. Suzukis have notoriously been easy to rail tight turns but had a tendency to headshake at speed in chop. Strangely enough, the bike doesn't seem any easier to turn but it doesn't seem to headshake as much. Go figure. Maybe the larger, more rigid down-tube helped out with stability. The controls are well placed, have a nice feel, and the bike seems to fit a wide variety of rider sizes. The fit and finish on the bike are very good, but we couldn't help noticing that the paint on the cylinder started to flake off after one ride and wash-down. Bummer. The yellow plastic does take abuse well, though, by not showing scratches that are easily apparent on other brands (namely Yamaha's blue). The front fender is a little flimsy, as usual. After the major redesign for 1996, we didn't expect Suzuki to make astounding changes for 1997 - they didn't have to. They had a solid 250 that was unanimously praised by the media and riders, alike. With help from their factory riders and race team, they simply went in. and made small refinements to an existing strong performer. Just how it performs against the other 250s will be decided in a few weeks. We could see some big changes next year, though, thanks to you know who. (N 1997 Suzuki RM250V Specifications Entl Uquld-cooled, single·cylinder two-slroke wi AETC/PC (Automatic Exhaust Timing Control/Power Chamber) Di",'s.. pt... . 249.3cc BoN x 66.4 x 72mm enItlo , 9.0-10.9:1 Cerburetlon Kelhln PWK38 Ignltion Electronlc T uion ' •..........six·speed F .......,;ty . , 2.2 gal. WMeIIIue . . . . . 58.3 Ibs. SNt height 37.4 In. Front tI Bridgestone M61 80/100·21 Ilear tI.. . Bridgestone M78 110/90·1g Front .showa adjustable 49mm Conventional Twin Chamber cartridge forks wi 11.4 inches of wheel travel IlNr ........illll .. . .. Showa adjustable shock wi 12.6 inches of wheel travel type Front...... . "-'....... . CIllIIHd'" MIgIIt Disc, duaJ.p1ston cailper Disc, single-piston caliper .215Ibs. ..................................$5,599 \,() 0'\ 0'\ ,.--l a M I-< Q) "£ u o 21

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