Behind the GB Racing guards rests an ESP-built engine that the team claims produces around 220 horsepower when fed with VP MRX01 fuel. It feels every bit that fast too. Notice also the swingarm pivot, which the crew says is up and forward compared to stock.
A Leo Vince full titanium and carbon exhaust and Carrozzeria forged aluminum wheels make for a lighter overall package. Below the swingarm you can also see ESP’s own rear shock link, which is flatter and designed to provide a more consistent feel through the shock’s travel.
Attack Performance triple clamps use inserts to adjust offset, and consequently, trail, which the crew uses to give riders more front-end feel. A GPR stabilizer is a must with more than 204 horsepower on tap, while an AiM dash provides more info than is feasible to understand at 150-plus mph.
A gas cartridge kit replaces the stock internals and provides a stiff initial feedback but a more stable feel through the middle of the corner. ESP admits that it typically takes some time for riders to get used to the pressurized fork, but that lap times are generally quicker. Brakes are a high-dollar Brembo setup.
The ESP BMW runs an AiM datalogger as well as a BMW datalogger. “We use the AiM system to measure battery voltage and stuff like that, plus for suspension travel. The BMW system is better for measuring TC intervention,” says Evan Steel, co-owner of ESP.
AMA Pro Racing’s volatile nature is not something that the media has overlooked in recent years. Many members of the press have been accused of being too brash when writing about the latest AMA regimes in fact. Too critical. Too pessimistic. The list goes on. The current establishment has given us less to harp on and the racing has thankfully improved, but as dyed-in-the-wool enthusiasts we still hesitate to say that American roadracing is back in its prime. Among the problems that currently plague the AMA paddock is the number of hurdles that lowly sponsored teams must jump in order to go—or continue—racing. One of the teams that looks to have found a way around these obstacles for the time being is Evan Steel Performance, which recently completed its third year of on/off superbike racing and is sporting a few more notches in its belt than most equally supported teams.
If you’ve ever read a story about one underdog or another, then you’re probably already familiar with the ESP tale. The team operates out of a small shop in Tucson, AZ, where co-owners Evan Steel and Phil Allison spend most of their days putting together race bikes, building engines, and performing general maintenance on customer bikes. Once the work subsides and the bills are paid, Steel and Allison refocus their energy on the team’s BMW S 1000 RR superbike, the same bike that Aaron Yates raced in the last two rounds of the 2012 AMA Pro National Guard Superbike series; midnight oil is apparently sold by the barrel out in Arizona.
Yates’ return to racing and success aboard the ESP BMW didn’t go unnoticed around the Sport Rider offices (“The Long Road Back,” January ’12), so when Evan Steel emailed El Jefe and mentioned that he was interested in having us test its S 1000 RR at Chuckwalla Raceway we were more than excited. Bradley, in particular, had his bag packed before Kent could ask, “Do you want to go or should I?”
Current AMA Pro Racing regulations admittedly favor the teams with fewer resources. Bikes are required to run the stock crank, rods and pistons for instance. The more expensive 16.5-inch rear wheels are no longer allowed, and “original front forks must be retained,” says the AMA, although aftermarket cartridge kits and aftermarket fork caps may be substituted. “I think the BMW is a good platform for a team like us,” says Steel, who goes on to say that “it doesn’t take a lot to turn the S 1000 RR into a bike that’s capable of running with the front pack.” Steel and Allison spend more hours developing the S 1000 RR than Evan’s words initially lead you to believe. “Phil handles most of the engine stuff and I handle the chassis stuff…but yeah we’re always working,” admits Evan.
The BMW’s engine abides by AMA rules and thus makes use of stock pistons and rods, although ESP admits that they’ve taken some material off the head plus ported it and done a valve job. The results are quite staggering too. “The bike makes 204 horsepower with the AMA-spec Sunoco fuel and around 220 horsepower with VP MRX01 race fuel,” says Evan, who goes on to confirm that the ESP-prepped S 1000 RR topped the AMA’s trap speed chart in race two at Road Atlanta in 2011 and in qualifying at Laguna Seca in 2010. Impressive, especially when you consider the team is up against factory-backed teams like Yoshimura Suzuki and Graves Yamaha.
The ESP BMW’s chassis is more heavily tailored and continually being developed by Steel, who’s gone as far as to design his own rear suspension link for the BMW, which is permissibe by the AMA’s rules. “Yeah, we designed our own link because the stock link seemed a bit soft initially, and then maybe gets a little stiff as it ramps up through the travel. Our link is flat, or as close to flat as we could make it, and stays the same through the entire travel so that is sometimes easier to tune with. It seemed to give the riders a bit more initial grip,” says Evan.
Further forward, stock fork internals were jettisoned for a costly gas cartridge kit and the BMW triple clamps for Attack Performance units that use inserts to adjust offset, and consequently, trail. “Trail is of course a pretty important adjustment for rider front-end feel, so we use [the Attack clamps] to be able to change the trail without changing ride heights, which affect lots of other things too, not just trail,” adds Steel. Out back, the BMW’s adjustable swingarm pivot has allowed the ESP crew to move the swingarm pivot point up and forward.
The rest of the ESP BMW package appears equally as appealing, especially when you consider how limited the team’s resources are. Top-of-the-line Brembo monobloc brake calipers bite on Brembo rotors, and are plumbed to a remotely adjustable Brembo master cylinder. Down low, a pair of Carrozzeria forged aluminum wheels send dollar bills dancing about your eyes, while a Leo Vince full titanium and carbon exhaust has about an equal effect. It’s what you can’t see that really adds some validity to the team’s effort though—the electronics. “The bike still has four riding modes, including a rain mode and three other modes that have varying levels of traction control intervention,” claims Evan. The ESP bike is also equipped with an HP (BMW’s own line of aftermarket High Performance accessories) ECU, AiM datalogger and BMW datalogger; “We use the AiM system to measure battery voltage and stuff like that, plus for suspension travel,” continues Steel. “The BMW system is better for measuring TC intervention, but we definitely use both every session.” Interestingly, the bike runs all of the stock BMW sensors.
What’s perhaps more important is that back in 2011, BMW stepped in and helped educate the ESP crew on the electronics, how to study the data and how to use the program’s adjustments to their advantage. “In 2011 we went to Munich and spent two days at BMW Motorrad learning how to operate the datalogger. And really I mean, it’s kind of cool having had a bunch of guys ride the bike (this includes a number of front runners like Jake Holden, Chris Peris and Aaron Yates) and having the datalogger systems, because you learn a ton,” says Evan.
My initial reactions weren’t too far from what Evan had expected. “Almost everyone who’s ridden the bike comes in completely exhausted,” he admits once I finally manage to wipe the sweat beads from my face. “Except Yates,” he continues, “Aaron didn’t really have a problem hustling the thing around the track. I don’t think his heart rate even climbed during the whole race.” As a hardly in shape journalist who sits behind a keyboard more than clip-ons, however, I found it difficult to wrap my head around how difficult it would be to run an entire race at AMA Superbike-level speeds. I didn’t do myself any favors of course by asking the ESP crew to leave Yates’ setup on the bike, which was much too stiff for my slower pace.
The ESP crew installed softer fork springs for my second session out and the changes were immediately noticeable, although I still felt like the bike was on the stiff side through the entrance of the corner. “The gas cartridge kit’s initial feedback is a bit stiffer for sure,” admits Evan, who goes on to add that, “the gas cartridge doesn’t move as much once the bike is on its side. It’s much more stable, more consistent.” The ESP crew goes on to confirm that most of its riders typically go back to a standard front end in search of that initial compliance, but ultimately go quicker on the gas cartridge kit. I can see why too; the bike feels extremely planted once banked into a turn and provides a good amount of feedback through a corner.
The Brembo monobloc calipers only add to the experience at the entrance of a turn, and are among the strongest brakes I’ve personally tested. Convenient, especially considering that the ESP-built engine is similarly one of the strongest I’ve ever thrown a leg over. The power doesn’t feel like it’s isolated in any part of the rev range, either. It’s everywhere. And it comes in abundance to boot. Put simply, I’m not surprised that the ESP BMW is continually in the upper end of the AMA’s trap speed charts, nor was I surprised by the bike’s willingness to wheelie off the exit of every single corner.
It’s not all about outrageous horsepower figures though. One of the big complaints we’ve had with the S 1000 RR over the years is that it steers a bit sluggish in comparison to the competition, but the ESP BMW is lighter on its toes, especially through a faster transition, like that between turns 12 and 11 at Chuckwalla Raceway. Credit here goes to the ESP BMW’s reworked geometry and forged aluminum wheels, which lighten the steering effort and contribute to a significantly lighter package. The bike is still heavy by AMA standards however, and weighs around 382 pounds after a race. Compare that to the factory-backed bikes we’ve tested in the past, which weigh right around 370 pounds when the checkered flag drops.
What impresses me more about the ESP BMW is the amount of grip that it offers out back. It still spins the tire with ease, mind you, but I went into the day expecting the 204 horsepower to all but spin the Dunlop tire on those Carrozzeria wheels. That was hardly the case though, and I was only left checking my pants on a few occasions, which I believe is a direct benefit of the ESP link. “I don’t think it’s perfect, and there’s definitely some stuff we’d like to try, but it’s not bad,” says Evan.
A lot of those superhero sensations came from having a properly tuned traction control system beneath me, I’ll admit. The ESP’s system feels much more manageable than a stock BMW’s, and its intervention is smooth enough that you can step the rear end out but continue driving forward. I’ll admit that I was unable to switch through the bikes multiple ride modes and see how the different TC intervention levels affected corner exits. “Aaron is the only rider who’s been able to switch modes on the fly,” says Evan, reassuringly. “In one of the races actually, when he was looking to get by one of the EBRs I think, he switched to the mode with less TC and used the extra bite off the corner to make the pass. When he went by he went back to riding with a bit more TC, since it made the bike a bit less work to ride.” Riding this S 1000 RR is hardly as simple as Steel and Yates make it seem, I can assure you.
THE WORK NEVER STOPS
Evan Steel Performance is the first to admit that there weren’t enough hours in the day or enough dollars in their budget to further develop its bike, but that being said, I can’t help but be impressed with the package that they showed up to the final races of the 2012 season with. Proof is in the pudding; the team topped the trap speed charts on more than one occasion, and finished near the podium in just about as many races. Its efforts and abilities haven’t gone unnoticed either. Erik Buell recently invited Aaron and the ESP crew to race under the EBR canopy in 2013. And if I were a gambling man, I’d bet my money that the results will be just as sweet.