Cycle News - Archive Issues - 1980's

Hop Up: Suzuki RM250E SC Racing's fast touch By Kit Palmer "If it only had more power it would be perfeeL" This is a common comment heard from 1984 Suzuki RM250E riders in motocross pits everywhere. Well, "perfect" might be a little far-fetched, but "helluva lot better" would be more reasonable. When we tested the RM earlier, we felt it was barely the best in its class because of its superb suspension and handling, not for its motor. I( Suzuki had added more ponies and a broader powerband, they could have clinched the Best 250cc Motocrosser to Date title, easily. They didn't, so Suzuki owners must find their own way to breath on the RM's motor. Enter SC Racing, aka Suzuki Country Racing. SC Racing is based in a Suzuki dealership called Suzuki Country 10cated near Riverside in' Norco, California. SC is heavily involved in motocross; a few local pros use the SC Racing modifications on their mounts. We decided to give our test Suzuki the treatment to see how fast it could go. The first major SC modification is cylinder porting by Mike Lentini. The next step is milling the head .010 in. In a move hoped to give the 1984 RM more low end, Suzuki installed a smaller carb~eto~ tha~. in 1983, a 36mm flat shde Mikum mstead of a 38. SC Racing feels the 36mm carb is too small for the RM, so they bore the stock carb to 38mm. The main jet is ~op~d.a few sizes to a #280, and the pIlot Jet IS dropped a #40. The needle jet was also changed to a Q-8. A Poly-air 3 air fiher from Moto-X Fox replaces the stock element for bette~ breathing: Indented holes i.n the aIrbo~ are dnlled out and plastic vents are mstalled. Aluminum clutch plates replace the stock steel plates, for better feel and grab off the line. The aluminum plates are optional from Suzuki. To eliminate the typical, annoying exhaust pipe rattles, the exhaust flange is installed upside down. That puts the hooks connecting the exhaust springs on the bottom, stretching the springs and keeping the pipe from flopping around. Stronger Maico springs replace the stock Suzuki springs. The SC Racing modified Suzuki is faster, much faster than stock. The power comes on slightly quicker but much harder, and it keeps pulling and pulling. When stock, the power signed off too earIy. There is bad news, though. The Suzuki didn't have much low end to start with, and after the mods, it had even less. This makes the RM harder to ride. When exiting tight turns, the RM will bog seriously, and it will not come on the pipe until the clutch is fanned a couple of times. When there is an abundance of traction, because when the rear wheel hooks up, the front end instantly climbs; so the clutch must be used very smoothly. That's also true when the ground is dry and slick - to keep the rear tire from spinning and sliding from side to side. So, to ride the RM quickly through the turns, the clutch must be used constantly. Luckily the aluminum clutch plates give the rider better control. But the aluminum plates are not as hard as the stock steel plates, so they must be examined often for wear. Beyond the turns, the modified Suzuki is hard to fault. It is fast. The power outpudeels very much like the '82 RM-Z, which is still considered as one of the best 250cc MX engines ever produced, but it, too, lacked low end. Getting the RM off the line isn't easy. It requires a lot of practice. When the clutch is dropped, the RM ju,mps off the line, then bogs, and when it finally comes on the pipe, the rear wheel spins and slides sideways. After many runs, we found out that first gear starts are the hot ticket, instead of the normal second gear starts. The RM jumped off the line quicker and much smoother with less bogging. Once first gear starts are mastered, holeshots will be very common on the SC Racing-tuned Suzuki. It takes more of the rider's energy ~ 00 0') ~ ~ C\l to pilot the RM in a race, because it is harder to ride. Fromnext-to-absoluteIy-no-Iow end to roost-killing, trench-digging horsepower at the ilick of the clutch lever, the Suzuki rider must have a firm grip to the handlebars. Bringing the Suzuki in for turns also requires more energy: Brakes on the RM aren't all that great in the first place and feel even worse slowing the faster Suzuki down. The people at SC Racing say the RM could be made even faster, believe it or not. They have been experimenting with pipes and RM 125 ignitions; they claim a new P.SJ. pipe adds considerably more power while the ignition gives it long/!T power. I( you want fast, SC Racing will give you fast, but for a price that isn't cheap. Excluding the ignition and pipe, the cost is around $325 for port109, milling an9 parts. Add another $395 for the pipe and ignition (includes stator, rotor and COl). SC Racing does offer parts discount for riders of their choosing, so check into it. For more information contact SC Racing at Suzuki Country, 2057 N. Hamner Ave., Norco, CA, phone 7141734-0640. • >- ;: ~ Freddie Spencer Team Honda Winner - Belgium Grand Prix Thanks for riding with Castrol- America's #1 Motorcycle Oi/. Engineered for Performance 401 Hackensack Avenue, Hackensack, NJ 07601 17

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