First Test: 2005 Suzuki RM125

For the past several years, the Suzuki RM125 has been a major contender in magazine shootouts and has claimed several championships on the racetrack. For 2005, Suzuki remains dedicated to mixing premix as it has made a number of changes to the RM125 and has no plans to abolish the yellow tiddler. It will continue to grow its two-stroke program even with its four-stroke assault in full swing.

The new RM may appear to be very similar to last year's model, but its updates will be noticeable once you're on the bike. The motor and chassis both received some serious reengineering, targeting some of the flaws of the 2004 bike. The motor gained a redesigned cylinder head and an all-new crankshaft with asymmetrical flywheel balance, similar to that of the '05 RM250. It is now fueled by a Mikuni TMX38SS carburetor with a power jet and throttle-position sensor to help make the power more usable. The Showa suspension has some revised settings; the lower fork legs got a new honed surface treatment for smoother fork movement; and increased oil capacity above the piston and shim stack allows for a more-progressive feel. The Showa shock uses a larger inner rod for increased oil flow under big loads. The rear brake caliper has been completely redesigned; the new shape is more compact to save weight as well as improve performance. Refinements were also made to the ergonomics: The footpegs have been pushed back 10mm; the shift lever has been shortened 10mm; and the rear brake pedal has been shortened 13.5mm. In addition to receiving a few other minor changes, the yellow machine is dressed in a new gripper seat cover and snazzier graphics.

Corey Neuer rails a corner... 

   

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Corey Neuer rails a corner at Piru Motocross Park. He praised the new RM's mid-range power.

Power Trip
The RM125 has enjoyed a great reputation for several years with respect to the motor, so for 2005, Suzuki technicians just made small but noticeable changes. Bottom-end power doesn't hit as hard as last year's motor, and a bit more clutch is required to get the revs up in tight corners. Midrange power is where the motor comes on mightily and pulls into a very strong top-end with a good dose of overrev. On our first day of testing, the stock jetting worked well, but it was a bit rich off the bottom-end and midrange so we put a leaner main jet in, went one-half clip leaner on the needle and went two turns out

on the air screw. During both days of testing, conditions were hot at 102 degrees, typical of Southern California in August. After adjusting the jetting, we found the motor was a solid package: not a whole lot of usable bottom-end but very strong from mid to top-end. Our beginner and novice-level riders struggled with the lack of bottom-end, but our pro and intermediate-level riders didn't miss it and even praised the hard-hitting mid and top-end power. Stock gearing is 12/50; we tried running a 51-tooth rear sprocket to help with the meek bottom-end. Some of our testers liked the new gearing, but some found themselves shifting much more than they were comfortable doing. With the 51-tooth rear sprocket, second and third gear rev out too quickly, and it requires a ton of shifting and sometimes in the wrong places—only the boldest or dumbest feel comfortable shifting on the faces of jumps. Slower riders may prefer a

51-tooth sprocket, but our advanced riders preferred the stock gearing and insisted the harder you ride the bike, the easier it is to ride. The transmission is super-smooth and shifts effortlessly under power with no hints of the evil false neutral.

Shock Therapy
Minor changes were made to the Showa for '05. In stock trim, both the fork and the shock are on the soft side. All of our test riders were in the bike's target weight range, yet all felt the suspension was soft and didn't absorb big braking bumps as it should. On the fork we found ourselves going a full eight clicks out on compression compared with the stock setting of 12 clicks out. The fork reacted to our adjustments, as the Showa suspension is very responsive to any tuning. The shortfall of this fork is it doesn't use the same Showa twin-chamber setup the RM250 uses. The twin chamber allows the fork to be much more progressive, which is what the RM125 needs. The Showa shock's updated feel is much more progressive than the fork. We ran the sag at 100mm, and that seemed to work best. We did try a bit more sag—approximately 105-108mm—to make the bike more stable in high-speed sections, but then the front end would push in tight corners. So after a bit of experimenting, we went in three clicks on compression and quickened the rebound two clicks. The shock had been packing up a little through braking bumps. With a few clicker adjustments, we were able to get it 100 percent dialed to our liking. The RM tracks great out of corners under hard acceleration and really gets the power to the ground. Traction was not a problem, as the rear tire stays planted and gives plenty of feedback, with no hidden surprises.

Suzuki tweaked the ergonomics a little, but the small changes were hardly noticeable: The bike still caters to all sizes. As with the RM250, Napoleon-sized riders may prefer a lower seat, but you'll need to do a seat swap only if you are extremely picky. Overall, the fit is right on the money. The enhanced brakes are incredible; the front brake has an abundance of stopping power, with no signs of fading. A nice feature the entire RM lineup received is a new aluminum handlebar; it has a very comfortable straight bend and was liked by all of our test riders. The new gripper seat cover feels as if it was built to last and offers quite a bit of grip over last year's cheap-feeling cover.

Big Benefits
If you're a racer who buys yellow, you may be rewarded with its huge contingency programs. Suzuki has raised the bar once again, boosting its contingency to more than $6.7 million for the '05 season. It also has huge trackside support at selected races across the country. The yellow crew will continue its Good Scholar Program for any student maintaining a 3.0 grade-point average. These smart young racers will be rewarded a U.S. Savings Bond worth $500. And one final bonus: Any buyer of a new RM125 is eligible for a free certificate to a Tony D. motocross school, which travels nationally.

Opinions

The 2005 RM125 is a fun bike to ride. The motor is really strong with a potent midrange, and it pulls all the way through the powerband. Mid and top-end are really good, and I believe the motor can be very competitive with the four-strokes. One thing I really like about the motor is it revved forever; it didn't sign off and go flat—all the power is usable. The suspension is pretty good. At first, the fork felt really harsh. It bottomed out on the big stuff and skated around on little braking bumps. I went four clicks in on compression and that helped a lot; it handled better and soaked up everything. The ergonomics on the RM were very comfortable. From the beginning I felt right at home on the bike. The one thing that stood out in my mind is the way the RM turns: Wherever I wanted the bike to go, it went.
Shane Smith/5'10"/168 lb/Pro

The 2005 Suzuki RM125 is a surprisingly fast and nice-handling motorcycle. The motor was extremely strong and smooth. It has the best stock suspension that I have ever ridden. Both ends have great bottoming resistance and a very smooth stroke. There were big holes on some of the jump landings, but they were not a problem, and the bike stayed in a straight line. The brakes are powerful with consistent, smooth stopping power. The RM never seemed to fall off at the top of the powerband; it just kept making power. The handling is exceptional. It seemed as if it were on rails through the corners. The seat is very comfortable with a bit more of a pocket to it than most bikes. The RM125 was better than I thought possible, and it should work well for beginners all the way to pros.
Derek Whitt/5'11"/180 lb/Novice