Inside the 2013 Supercross Works Bikes

The start of a new Supercross season brings with it a lot of anticipation over and above race results. It’s the first time fans, riders and team personnel get to see what the competition has brought to off-road racing’s largest stage.
The recession has no doubt slowed some of the progress, however, that hasn’t stopped much in this sport. During the last few years we have seen tremendous advances in ignition systems, electronic fuel injection, front suspension, and now, for 2013, shock technology.
KTM is the first to introduce an air shock to modern racing. The idea is not new in principle, but it does break a longstanding tradition of externally sprung components. The new WP air shock is enshrouded in mystery that has suspension technicians intrigued.

Like most air shocks, the external coil spring is absent, as on Dungey’s KTM 450SX. We don’t know for sure if there is any type of internal spring, although suspension experts believe there may be one to control top out.

Ryan Dungey’s KTM 450SX is using the latest developments in air-shock technology for 2013. The use of air instead of a metal coil spring for suspension systems has been advanced by the Kayaba Pneumatic Spring Fork in the 2013 Honda CRF450R and 2013 Kawasaki KX450F.

Dungey’s shock has a braided line that leads from the shock body to the airbox, and it’s not known if this contains data-acquisition components, some type of smart or active technology, or perhaps air lines to another hidden area. One of the challenges with air shocks is controlling heat, and thusly, air pressure. The braided line on Dungey's bike may be ameliorating the heat/air pressure issue.
There are traditionally two different types of air shocks and each has its own set of advantages and disadvantages. The first is the air bag or bladder-style air shock, and these can use one or two separate air chambers to control force. The second style is the telescoping cylinders like the original Fox Air Shox, but the disadvantage here is seal drag, which is one of the challenges of the new wave of air forks now being used on production motocross bikes.

The most-interesting aspect of Dungey’s works bike is this new WP air shock. KTM officials kept photographers out of the pits and wouldn’t allow up-close photography, so we got this photo as the bikes lined up for the first heat race at the Anaheim Supercross. Because of the innovation, KTM had more suspension technicians in the pits than any other manufacturer and all eyes and ears were on Dungey every time he hit the track or returned to the pits to provide feedback.

We spoke to Race Tech’s Paul Thede who says no one will know what type of technology WP and KTM are employing until they want to let the secret out of the bag. There are too many variables that come into play, but Thede does believe damping would be along the lines of traditional style with oil running through small orifices such as valves and shims.
Another trend seen in the pits is the conversion to Showa suspension by everyone except KTM and privateer Josh Hansen. Hansen’s Kawasaki is one of the last bikes to use Kayaba components.
We got terrific access into the Anaheim 1 pits and snapped a ton of photos that reveal many key details of the exotic supercross machinery, so scroll down to see what we discovered. 

Ryan Villopoto and his mechanic Mike Wilkinson are almost inseparable at the races. The two have been working together for several years, and there is arguably not a better combination on the circuit.

Ryan Villopoto uses this custom seat to help him stay secure on the bike under heavy acceleration.

The hubs on Villopoto’s KX are reported to be two ounces lighter than stock and definitely add to the bike's appeal.

Chad Reed’s Honda is a full-on works bike, and that includes the exotic Showa suspension valued at $62,000. Only one top rider uses KYB suspension: Kawasaki’s Josh Hansen.

The exhaust pipe on Chad Reed’s Honda is extremely exposed, but engineers couldn’t figure out any other place to add length to the exhaust which ultimately provides power that is robust yet controllable.

Eli Tomac’s Honda CRF250 runs a single exhaust unlike his 450 teammates. Tomac says the single pipe gives him more bottom-end and midrange power that he and his teammates like for supercross.

The billet aluminum gas tank caps on Josh Grant’s and Justin Brayton’s Joe Gibbs Racing Yamahas are nothing short of eye candy. The sleek design allows the riders to move further up over the front end of the bike.

For the past three years, JGR Yamaha has partnered with GET for their programmable ignition systems, allowing fine-tuned settings for any track and any condition.

The JGR Yamahas have one of the most unique exhaust systems seen in the pits. It reportedly helps take some of the bite out of the bottom-end power while retaining a healthy midrange.

Yamaha’s YZ450F motor reportedly produces the most power out of all the 450s, and KTM is incredibly close. Throughout this recession, KTM has consistently been the manufacturer to introduce the most innovation.

This season marks James Stewart’s second year riding Yoshimura Suzukis. The RM-Z450 is one of the most forgiving bikes and suits Stewart's style better than anything else except maybe the Kawasaki.

Most of the top riders use an adjustable ignition system that they can change on the fly. All they have to do is flip the switch to the right of the kill switch.

James Stewart prefers to have his seat made with a bunch of little raised areas with heavy-duty stitching. It’s a different way of accomplishing the same thing as the seat bumps used by so many other riders.

Yoshimura uses a traditional style exhaust.

Exotic billet parts replace cast components of production bikes.

Stewart runs a brake snake to prevent his brake lever from being bent back.

Kevin Windham’s rides a factory Honda with works suspension tuned by Works Connection. Windham has his custom ignition programmed for more bottom-end power than other riders tend to like.

Windham prefers to use Yoshimura’s dual-exhaust setup. It adds a bit of weight but can radically impact power output and delivery.

The exhaust on Windham’s Honda CRF450R doesn’t use a canister like Chad Reed’s full works bike. Notice the difference between the two setups when you go back and compare photos.

This bike is really similar to last year’s machine ridden by AMA Lights National MX Champion Blake Baggett. Pro Circuit unquestionably has the best competitive record in the Lites class, and the genius behind that is a former off-road racer named Mitch Payton.

You can buy the same fork used by the Monster Energy Pro Circuit team for $6500. The price is really steep, but you won’t find a better fork on the market unless you earn a coveted factory ride.

The ARC levers used on Blake Baggett’s KX are available to the public and spring forward to reduce the chances of failure during a crash. They are not unbreakable, but they are really good.

Baggett’s mechanic prefers to run fine-coarse foam under the brake pedal to make sure nothing interferes with its action.

Baggett and the rest of his team use the canister-style exhaust.