Suzuki made huge strides with...
Suzuki made huge strides with the RM125 power delivery.
Until this year, Suzuki has been without a four-stroke motocrosser of any size, yet it has been forced to race against them in both eighth- and quarter-liter classes. For 2004, Suzuki finally acknowledged that Yamaha and KTM two-strokes may be on to something with their obsession for midrange torque, and that same thinking counts double with four-strokes. Since the RM125 will be sharing starting lines with four 250cc four-strokes, including Suzuki's own RM-Z250, it needs to deal with their threat.
As a result of setting a new target--competing with four-strokes--the 2004 RMs have mega motors. Suzuki left no stall shut in its efforts to set free more midrange ponies without hobbling the existing thoroughbred high-rpm rush. The search for new horseflesh required a 125 overhaul that included a longer rod, an all-new port layout and a totally different exhaust valve setup (similar to the one on the '03 RM250). But, what the hay, it worked.
What's New
• Seat 10mm lower than '03.
• Quick-adjust clutch perch.
• Suspension has refined valving front and rear, with redesigned compression valve for better hookup with new link.
• Linkage rods attach to swingarm rather than frame.
• Redesigned front-brake master cylinder and Honda-style hose routing for aftermarket performance now come stock.
• Wheel drag is reduced via a floating front disc and a new carrier in rear.
• One-piece rear master cylinder/reservoir.
• Flat-top piston (lighter) for more bottom power via a closer squish area.
• Cylinder with nonbridged exhaust port and exhaust subports.
• Transfer or boost ports have greater volume from the cases up for bottom hit.
• Went from a two-piece exhaust valve to a large single valve and small subport valves to make engine respond more like YZ250F.
• Crank inertia is increased 6.5 percent for more roll-on.
• Airbox like '03 RM250's, with intakes in sidepanels for cool air and straightened airboot and manifold.
• Shift stopper spring stronger and detents more solid as on RM250 for more positive shifts.
• 125 has '03-style triple clamps with 24.5mm of offset rather than 22.5mm as on the '04 RM250.
What's Hot!
• Power is much improved with stronger, meatier midrange that lets the RMs pull out of turns and up hills with authority.
• Ergonomics are improved, with new seat shape allowing the rider to sit more in the bike than on it.
• Improved braking feel and power.
• Rear suspension action is improved, and new linkage allows the RMs to track straighter than ever.
• Handling is still nimble with very accurate steering.
• Very light feel on the track or in the air.
• Showa suspension offers great bottoming control.
• High-rpm rush that made the RM125 famous is stronger than ever.
What's Not!
• When engine drops below the midrange and falls off the pipe, it falls off hard and needs a fair amount of clutch or a downshift to get back to race acceleration.
• Suspension soft for some pro riders. |
RM125 For the last few years Suzuki and Yamaha have tossed the leadership of the 125cc class around like the spud in a child's game of hot potato. Yamaha has headed home with the tater more often thanks to its bark-in-the- middle-but-rev-on-top motors, but Suzuki's aim at a four-stroke target may change that.
Our initial test was on Cahuilla Creek's natural-terrain sand track. If a manufacturer wanted to make its 125cc motocrosser appear slow, Cahuilla's deep, loamy uphills would be the place to debut it. Within a few laps we realized the venue was not a mistake. Only days earlier we had been at the same track with the '04 KTM 125--long judged the powerhouse of the class. Without a back-to-back comparison it is difficult to be certain, but the RM feels as if it has approached the mid-bark of the KTM with little tendency to go flat on top.
Suzuki prejetted the machines, yet we still played with the jetting--swapping the needle to get a difference approximating a half-clip richer at one-quarter throttle. We also went up one tooth to a 51-tooth rear sprocket. The changes allowed the fast guys to stay in third in the faster sweepers and let the less-aggressive riders string crucial upshifts together up the hills.
Our usual 125cc-class pilots opted for suspension settings fairly close to stock, though we did stiffen the compression three clicks in the front and one in the rear for the downhill braking whoops, as well as slowing the shock rebound one click for control in the same area. Overall, the bike was easy and satisfying to set up for a variety of riders, from cranking 125cc-class intermediates and pros to editors claiming they were justified by sheer fun--but with no valid excuse for torturing a 125 on a hilly track.
Cahuilla provided ample opportunities to sample the RM's high-speed manners, since several sections of high-speed, downhill braking bumps were initiated in fourth or even fifth gear. If you are counting, that leaves one gear unused since Suzuki is the last major 125cc-class competitor to possess a sixth ratio in the box. As you'd expect at speed on a soft but lumpy surface, the RM demanded attention and caution but never proved downright unruly. Its Dunlop D739s gave surprising performance in the soft dirt, but where it was loose or recently watered, the front did some ice-skating that left us wishing for a Dunlop D742 or D756--or even a D773--some meat that would have been more at home in the sand.
The fat midrange of the RM125...
The fat midrange of the RM125 makes jumping easy.
Aside from choosing the wrong dancing shoes for the debutante ball, we found little fault with the RM125 and a lot to like. By building on a knowledge base fostered by decades of national and world championships, Suzuki has molded the RM125 into a platform that is strong on any performance scale. In addition to boosting the performance on all fronts, Suzuki expended more midnight oil reducing drag on the wheels, while strong-arming the accountants for better grades of hardware and making veiled threats to the quality control department. It also added a quick-adjust clutch for the first time and upgraded the seat foam to a stiffer compound that was well-received by the staff.
If Suzuki is as accurate about the peripheral enhancements as it was about performance, it must be anxiously awaiting the next inning in its eternal game of hot potato.
Opinions
The 2004 Suzuki RM125 is a very solid package. The little yellow zinger has good bottom-end snap and decent midrange pull. The top-end is plentiful, with the overrev maybe needing some help. I ran a 51-tooth rear sprocket instead of the stock 50-tooth, which helped me pull third gear instead of going down to second. The suspension is a little soft for my big frame, though on big slap-down landings there was no metal-to-metal clanking at all. I could use heavier springs on both ends. The little Suzuki turns very well, and its ergonomics are comfortable. I like the new seat better than the '03 seat--the foam is firmer and shaped better. The 125 will be a contender in 2004!
Kris Keefer/5'11"/170 lb/Pro
The 2004 RM125 is a very strong bike. The suspension is golden; it is extremely steady through all the bumps and solid through braking bumps. The power is pretty good, too. The middle is strong and the top is decent, but it could use some help on the overrev. I jumped onto the bike and immediately felt comfortable. The bike turns well. I'm impressed.
Tyler Keefe/5'10"/160 lb/Intermediate
The RM125 has always been one of my favorite 125s--partly because the handling characteristics are great for my weight and riding style. This bike is no exception. The RM handles and turns remarkably. The suspension felt good overall but the rear end seemed a bit twitchy at higher speeds. The new seat is stiffer than last year's but still soft enough to keep your ride pleasant and help prevent monkey-butt. The motor makes decent power from the lower end of the powerband to the middle. Like most 125s, the RM puts out the most power from mid-to-top. I like the strong mid, but it paid a price in low-rpm pull. If you make a mistake and lose a little momentum, it takes some serious clutch abuse or a downshift to energize this bunny again.
Brad Daugherty/6'/160 lb/Intermediate