How much better is Stefan Merrimanâ€™s race bike than the standard WR450F it started life as? We put them head-to-head and against the stopwatch to find out. ANDY WIGAN
hen Yamaha’s alloyframed WR450F arrived in 2007, it made a chookchaser of the existing WR450F. Compared with the old steel-framed, squatin-the-arse bus, this flash new ’07 model was modern, predictable, nimble and housed one of the most deceptively fast powerplants the enduro world had ever seen. The Europeans finally stopped calling the Yamaha a clunky overweight trailbike, and the machine has been at the pointy end of enduro competition ever since. No one batted an eyelid when the ’08 model arrived without any significant mods, but when the 2010 model hit dealer floors, Yamaha fans could hardly hide their disappointment. It was essentially the same machine that Yamaha rolled out back in 2007.
No new reverse cylinder, no EFI, not even a digital speedo pick-up to replace that crappy cable that looks like a garden hose running down the fork leg. All of which means there’s been a growing gap between the standard WR450F and the WR450F machines you see under race team awnings these days. While guys like Chris Hollis and Jarrod Bewley rode nearstock WR450Fs to AORC and A4DE victories a few years back, modern-day WR450F race bikes are increasingly morphing into different animals altogether. Some run YZ450F components, while others are simply the beneficiaries of all the aftermarket parts now available for the WR450F. So when you’re bench racing with mates, it’s easy to get swept up with the idea that these race team bikes are so much lighter,
faster and smoother, that you too could win races aboard one. But do these tuned and tweaked race bikes handle better for everyone, or just the Pros they’re developed for? Are they actually easier to ride, or do they require Pro-perfect throttle control? And after a long day in the saddle, would you be faster on one these race bikes or aboard the standard stead sitting in your garage? These were all questions we’d thrown at each other in the office in recent months, and after two days of loamtown laps around Geoff Ballard’s “Ballaranch” enduro loop and a fast grasstrack nearby, we had some answers. At least, we had an overall picture of the standard and race bikes’ pros and cons, and an insight into the time and effort the wily Stefan Merriman has put into developing his race machine.
FIRST IMPRESSIONS OF MERRIMAN’S BIKE?
HOW DO THE COCKPITS DIFFER?
Okay, it doesn’t take an honours degree to make the observation that Merriman’s race bike is nicer on the eye than the plain-Jane stocker, but the difference is far from window dressing. Everything on his race bike is functional; it just happens to be good-looking, too. The Akrapovic exhaust system, the 7L clear tank and YZ-F shrouds, the Acerbis headlight and handguards, the de-cluttered handlebars and the nice little blue GYTR bling bits, all combine to give the #21 machine a lightweight, purpose-built, racy aesthetic. There’s also a noticeable void behind the cylinder where an electric starter once sat.
Merriman’s Tag handlebars are swept back 5mm more than the standard Pro Taper units to help the vertically challenged champ get further back on the bike when the need arises. Other than that, and the GYTR gripper seatcover, you could close your eyes and be on a standard WR450F. The clear YZ450F-spec tank is a litre smaller than the WR-F’s stocker, but the race bike’s ergos aren’t any noticeably slimmer. The most obvious difference in the cockpit comes when you finger the controls. With a revised leverage ratio, Merriman’s clutch-pull is way lighter than
the standard bike’s, as is his throttle action. This is care of a mod done to the throttle wheel’s return spring at the carb. With your eyes open in the #21 cockpit, you soon notice all the switchblocks and instruments have been ditched and there’s no electric start button. With a lightweight Acerbis headlight and handguards replacing the chunky standard units, the minimalistic approach saves a fair bit of weight off the bars, where weight is really felt. Meanwhile, the funky fork caps reveal the WR450F’s standard 48mm KYB fork has been replaced with twin-chamber units off a 2010 YZ450F. The only addition to the bars: the yellow Vortex dual ignition switch.
The WR450F hasn’t changed since ’07, so there’s a growing gap between the standard bike and the WR450F machines often seen under race team awnings.
#21 BIKE MODS
SPANNERMAN FOODGE… Peter “Foodge” Burrell has been swinging spanners for Stefan Merriman since the champ returned to Australia at the end of 2008 and joined the Ballard’s Wellard Yamaha team. Together, the boys spend an enormous amount of time testing and developing the race bike. We asked Foodge to run through the list of parts and set-up options they’ve tried. FOODGE: “We’ve tried a lot of stuff – a 400cc kit, Rekluse auto clutches, different brake combinations, different gearing combinations, different ignitions and flywheels, lower compression setups, different triple-clamp offsets and
different carby settings of course. I mean, we’ve even tried throttle tubes that limit the throttle pull to half the travel. If it can be tried, we’ve done it. Stefan even tried drinking the night before a race six or seven years back in the WEC when the Finns were on the turps the night before racing and still beating him! It didn’t work [laughs]. He’s the only guy I know who plays around with his bikes more than Geoff Ballard, and that’s saying something. Even though we’ve often ended up back at, or near, standard settings with the bike, we learn a lot during the process. I mean, these bikes are that good these days, you can go and
win a world championship on them with relatively minor mods. “Stefan runs his rear brake pedal high and insists on it having lots of feel, and you can see the trials background coming out in him by the way he rides the bike so smooth at low revs. Because of that, a lot of our work with the engine has been about getting the bottom-end and mid-range right. For guys like Stefan who carry fantastic cornerspeed, the reality is they’re rarely at full throttle. Stefan uses a much different technique to motocross riders, and he’s very gentle on clutches. I’ve never seen him burn one out. Unlike GB!”
So just how removed from a standard WR450F is Stefan Merriman’s race bike? Here’s the main stuff:
SUSPENSION & CHASSIS • 2009 YZ450F fork • Fork Seal Savers • Revalved shock • Ballard’s front wheel spacer • Metzeler MC4 110 rear, 6-Days soft front
ENGINE & DRIVETRAIN
ERGOS & BRAKES
• Vortex ignition • Akrapovic exhaust system • Hinson clutch basket • GYTR clutch cover • Uni Filter air filter • Hammerhead case saver • Talon sprockets (13/50) • DID VT2 chain • Electric-start removed • Reinforced (Quicksteel) magneto cover • Cut-out bashplate • Yamalube 10W-40 semi-synthetic oil
• Kustom MX graphics kit, GYTR gripper seat cover • Acerbis headlight, disc guard & handguards • Pivot Assist clutch lever assembly • Tag 9661 handlebars • Clarke 7.15L clear tank • Solid rear brake disc • Braking Batt Fly front disc & pads • Quick brake pins, Brake Snake • Goodridge brakeline • Ballard’s tail-light extension • GYTR chain guide • GYTR folding front brake lever • GYTR blue bling bits
HOW DO THE MOTORS COMPARE? The biggest difference between the powerplants is not their outright power, but where it’s delivered in the rev range, how it responds to throttle inputs, and the exhaust note produced by the Akrapovic versus standard system. The combination of Vortex ignition, Akro pipe and spot-on jetting has given Merriman’s motor noticeably more response at low revs. As you would expect from a rider with a trials background and who always seems to ride a gear taller than his opponents, Merriman has focused his race bike’s power toward the bottom and mid-range, and then fitted a steel Hinson clutch basket to ensure it retains a tractable, userfriendly character. Not only does the steel basket create a more durable clutch, it also acts like a larger flywheel weight to smooth out the power delivery. So while Stefan’s motor is more aggressive, it’s actually more forgiving and versatile at the same time. It’s much easier to shortshift and torque around in tall gears, or to loft the front-end over tree roots, rock ledges and whoops that appear at an instance’s notice. And it gives you the confidence to clear jumps, even if you’ve messed up the corner right beforehand. That sweet combo of instant, responsive power in a taller gear makes the race bike much easier to ride through ruts, berms, flat corners, flowing trail and rough terrain. And it means you can get away with less gear changes, too. Interestingly, Merriman’s bike has noticeably less top-end than
the stocker. If you try to hold gears too long, the power flattens off pretty quickly so you’re much better off taking advantage of its torquey mid-range. So while the standard bike takes longer to build revs, its overrev is handy around a fast grasstrack. It’s also why the Yami has won shootout drag races for years.
WHAT ABOUT MERRIMAN’S SUSPENSION MODS? Merriman runs a revalved KYB shock with standard spring rate, and there’s very little difference between the two bikes in the way the shocks behave. The 2009 YZ450F fork on the race bike, on the other hand, has a significant affect on the chassis balance and feel. The firmer twin-chamber YZ450F fork does give away 1020% of that plush feel over small trail debris, but it also produces much better bottoming resistance when you flat-land jumps or charge big-braking bumps. On bumpy downhill sections, the motocross fork sits up much higher in its stroke and resists the soft standard fork’s tendency to dive when you hit the anchors. This keeps the chassis a lot more balanced and predictable, and it lets you steer the bike into turns without fighting the front-end nearly as much. At slow speeds on the trail, the user-friendly standard front-end actually offers better steering accuracy as it sits down in its stroke, but the thing soon finds its limits when a faster rider gives it a nudge. At speed through the whoops or braking bumps on the
“With these elite Pro riders, there are a number of different ways of coming up with the same result on the stopwatch, but they’ll choose the one they feel the safest with.”
grasstrack, you really notice the difference between the two frontends. Even with the compression clickers dialled up, the standard fork uses up all of its travel and then some, while the front-end on Merriman’s bike retains its poise and contact with terra firma, and gives you the confidence to brake hard without thinking the frontend is about to let go as you tip in. Of course, none of this should really come as a surprise. We all know that the WR-F fork is set-up for the average 80kg trailrider Merriman hits things a lot harder and faster – and under much bigger braking forces – than the average trailrider. Basically, his suspension set-up is all about building a greater safety margin into the fork so he can smack things hard, while retaining the bike’s inherent drive and tractability with a near-standard shock.
– GEOFF BALLARD
ARE MERRIMAN’S BRAKES BETTER? Braking’s Batt Fly front disc earns its lofty price tag on the grasstrack where its one-finger application produces awesome stopping effect. Combine that with the firmer feel of the YZ-F fork, and you can push the #21 bike much harder into corners. On the rear, Stefan runs a solid rear disc (like most of the top EWC guys) and this makes for a really nice, progressive feel on the pedal. When you’re getting tired, an accidental Clydesdale-hoof on the rear brake doesn’t instantly stall the motor, and it’s much easier to modulate the rear brake in tight or technical terrain.
LAP TIMES… Here are the average lap times cut by each rider around the Ballaranch enduro loop... RIDER
Merriman’s YZ450F fork makes the race bike much more poised under brakes.
GEOFF BALLARD’S TAKE...
One of the things that’s helped give Geoff Ballard such longevity with his off-road racing career is that he’s always been prepared to learn from the riders he employs. And by GB’s own admission, he’s learned a whole lot since Stefan Merriman has been under the Ballard’s Wellard Yamaha tent. We asked GB to give us a team manager’s insight into the multiple world champ.
is completely the opposite. I’ve never seen a rider with his sort of work ethic. He does an amazing amount of work with his training and with developing the bike. He’s one of those guys who thinks he has to do the work, and feels that he’s behind the eight-ball if he’s not flat-out and focused on the job. He literally never stops thinking about the bike and his riding, and that’s why he’s such a good tester and developer.”
HIS WORK ETHIC: “With that many world championships under his belt, people tend to think Stefan has to do bugger-all to be on the pace. The reality
DEVELOPING THE BIKE: “Some of his ideas are outside the square, but he’s not afraid to try something unconventional. One thing we’ve all
learned from Stefan is that, with everything he tries, there are good points and bad points, but it’s always about the stopwatch. Always! He might do a mod that makes him faster that, for instance, also makes the bike harder to start. So in the end, he might decide against it. He is constantly trying stuff and quietly weighing up the pros and cons. It’s a conservative bike set-up philosophy he’s developed over years of experience, and it’s pretty similar to the way Yamaha goes about developing their bikes. He’s ridden a lot of different bikes in his time and he’s so refined in his riding, so he picks up on the
smallest little things when testing. One thing I‘ve learned with these elite Pro riders is that there are a number of different ways of coming up with the same result on the stopwatch, but they’ll choose the one they feel the safest with. “These top guys are right on the limit, so they might even sacrifice a little bit if they feel it’ll help get them through a season with less crashes. The fact that Stefan runs the YZ-F fork on his race bike is a perfect example of this. It’s not as plush on the small stuff, but it won’t punish him if he over-jumps something.”
SET-UP PREFERENCES: “Some things just don’t seem to bother him. He’ll jump on someone else’s bike with goofy bars and adapt to it immediately. The one thing he has put a lot of work into is getting second gear right. It might sound a bit funny, but he’s always thought his bike had too much power coming out of really tight corners, whereas third gear smoothes everything out. He wants the smoothness of third gear in second, and has played around with countless combos to achieve that. Ultimately, he’s ended up back near stock, but he’s learned along the way.”
WHO DOES THE STOCK BIKE SUIT? Despite remaining unchanged for four years, the standard WR450F is still very hard to fault for the average trailrider who does 100 clicks with mates every second Sunday. It’s so user-friendly, stable and predictable that, at the end of a long day in the saddle, most trailriders would prefer to be on the standard bike than Stefan’s if confronted by a big, snotty hillclimb. Guys heavier than 80-85kg who know how to give it a nudge will need to firm up the fork, but that’s about it. Matched with proven reliability, the WR450F continues to sell in prodigiously big numbers for good reason.
“The biggest difference is the race bike’s firmer fork, punchier bottomend and super-light controls.”
PRO: DAMIAN SMITH
35, 67kg, 180cm “I felt comfortable riding both bikes, and the biggest differences for me was the firmer fork and lighter controls on Stefan’s bike. The standard fork wore me out quicker as I was pushing it through the stroke much of the time. Stef’s YZ fork is a lot firmer and felt like it could take on anything, so I really liked the more balanced feel it gave the entire chassis. The rougher the track got, the more I liked the race bike. Not just because the YZ fork didn’t fall into holes, but because its snappier throttle response helped me pick my way through bumps and obstacles. I can’t overstate how good the feather-light clutch pull and throttle action made Stef’s bike feel. When you’re tired and your hands are cramping, little things like this make life so much better – whether you’re a Pro racer or an average trailrider. The race bike package is very good, but it’s not massively different from the standard bike. It’s just improved in the few areas it needs it. This is exactly what I expected. Stefan’s such a bike connoisseur.”
VET: GARRY BLIZZARD 41, 87kg, 178cm
“I’d thought Stefan would have run a lower subframe as he’s short, so it surprised me how standard the whole ergos set-up was. For your average trailrider, the fork on the standard bike gives it a more stable, compliant feel in the front-end, as trailriders simply wouldn’t be using all the suspension travel with the YZ-F fork. But when you start to give it some, Stefan’s fork was a lot more forgiving if you got it wrong. It was streets ahead on the grasstrack when you hit the braking bumps and it gave me the confidence to brake hard and tip in. I was in two minds about the extra throttle response and bottom-end punch on Stef’s bike. Initially I thought it’d wear me out quicker, but I realised it could actually help get me out of trouble by clearing jumps and obstacles with confidence. The light controls on the race bike were fantastic. Along with the de-cluttered handlebars, it’s amazing how that weight saving can transform the feel of the frontend and help it steer more precisely.”
43, 90kg, 182cm “The race bike’s aftermarket headlight and handguards, clear tank and sweet-sounding exhaust all added to its sex appeal, but I’m not sold on the idea of removing the electric starter. I’m too heavy for the standard bike’s fork, so I really liked the extra confidence the YZ450F fork gave me to hit things hard, and I really don’t think it gave away much plushness on the trails. Best of all for me though was the extra response and grunt Stefan’s bike had. I could short-shift it much easier and dial the power on smoother and with less gear changes. I liked the option of the Vortex ‘mud curve’, but couldn’t notice much difference with it. If anything, it subdued the bottom-end and made it come on a bit harder in the mid. In a perfect world, I’d take a stocker with one YZ450F fork leg fitted, a pipe for a bit more snap, and the same super-light clutch and throttle pull as Stefan’s bike. If Yamaha goes a shameful fifth year without changing their WR450F, they could do worse than those mods.”
WILL YOU BE FASTER ON THE RACE BIKE? According to the stopwatch, Damian Smith and Garry Blizzard posted similar lap times on the two bikes around the Ballaranch enduro loop. The interesting thing was that when the track got rougher and our test riders fatigued, Smith went comparatively faster on the race bike, while Blizzard was quicker on the stocker. Why? According to Smith, it was a combination of three things: the standard bike’s fork began using too much of its stroke and wore him out, its less responsive power didn’t allow him to keep the front-end on top of whoops, and its heavy clutch and throttle action was punishing on his tiring arms and hands. On the flipside, Blizzard was using less fork travel, so its plusher action was kinder on his arms as he clocked up the loops. And the stock bike’s super-smooth power delivery helped give him traction and smooth drive through the technical sections. Merriman, meanwhile, was between two and four seconds per loop faster on his race bike, which is a cold, hard, quantified endorsement of all his development work with the bike. It’s amazing how many race bikes are developed in isolation ... and then tuned to a standstill! Not Merriman’s. This bloke isn’t a four-time World Enduro Champion because he doesn’t understand bike set-up. As Damian Smith put it, “Stef is a bike connoisseur, and he’s crafted a fine wine with this race bike.”
MORE ONLINE... For footage of this race bike versus stocker test and feedback from Transmoto testers, plus video interviews with Stefan Merriman, Geoff Ballard, and Ben Burrell, check out www.transmoto.com.au