One of the chinks in the CRF450’s armor is the clutch. The stock four- spring clutch can’t handle the rigors of hardcore racing. Wiseco Performance is no stranger to Honda’s works-style stock clutch. To eliminate any possible issues, Wiseco revamped the CRF450 clutch by switching to their proprietary six- spring clutch. It was comprised of a forged inner hub ($279.00), forged pressure plate ($169.50) and clutch pack kit that included all the friction and steel plates, as well as springs ($160.18 for the kit). The clutch over- haul might seem like overkill, but unless you use the CRF450 clutch judiciously, it’s a very good idea to upgrade to the six-spring system. The MXA wrecking crew stated in our CRF450 test that, “Job one is to get stiff enough springs in the Kayaba forks to keep the front high enough to compensate for the stinkbug stance.” Wiseco Performance must have read the test, because they enlisted the services of Pro-Action to revamp the suspension. Pro-Action revalved the forks and shock, and also installed stiffer fork springs to keep the front end up ($435.00 total cost for revalving and springs). Other performance modifications included a Yoshimura RS- 4 titanium exhaust system, Pro Wheel hubs and wheels, Dunlop MX51 tires, as well as a Braking 270mm front wave rotor and standard size rear wave rotor. We have always been impressed by Wiseco’s attention to detail. In our last test they outfitted their project YZ450F in an all-white plastic ensem- ble with red and gray accents throughout. The Wiseco Performance CRF450 relied on custom red/silver/black graphics from Johnny Signs. Along with the unique design scheme, Wiseco swapped the stock black radiator hoses for red CV4 hoses. They also used Cycra M2 pivoting hand guards, Renthal bars, dual-compound grips, gold O-ring chain, and sprockets (with the stock gearing specs). TEST RIDE: TWISTING THE THROTTLE Although we paid attention to every area of the Wiseco Performance Honda CRF450, we were most interested in the EFI Controller. Wiseco gave us a short tutorial on how to properly install the plug-and-play Controller. The mounting process requires a few easy steps. (1) Remove the gas tank. ( 2) Disconnect the sensor cord on top of the throttle body. ( 3) Attach the Controller plug to the open sensor on the throttle body. ( 4) Route
the Controller wiring along the frame rail toward the top gas tank bolt, fol- lowing the other wires along the frame. Doing so will allow the rider to make quick changes without hav- ing to plug into an external device. How exactly does the EFI Controller work? It contains three zones of operation that are similar to a carburetor. One zone sets the pilot jet for idle. The second zone sets the needle for acceleration. The third and final zone sets the mainjet for heavy loads and wide-open throttle. Wiseco’s goal with the EFI Controller was to offer the option of truly fine- tuning your fuel-injected bike just like a carbureted bike. We began with a specific base set- ting and then deviated from it by making incremental changes. The goal was to feel the effects of the EFI Controller and then improve the engine’s performance. After experimenting with 16 differ- ent settings, we found the goose that laid the golden egg. However, we should preface this by saying that early on we found other settings that we liked, but we couldn’t stop pressing the buttons and making new fuel settings after every lap. Several times we zeroed in on really great settings that moved the power- band around to our liking, but we didn’t rest until we reached what we thought was perfection. There is one caveat. The EFI Controller did not make the CRF450 faster. What it did do was move the position of the power around in the powerband. This was a big plus. It allowed test riders to fine-tune the powerband to suit their riding style. If they wanted more low-end, they could get it. If they wanted more top-end, they could get it. And, while the bike never got physically faster, the rider could go faster when he had a powerband that was custom- tuned to his riding style. MXA’s favorite fuel setting focused on the midrange so that we could ride the bike a gear higher and lug it down without flaming out. Exhaust system: The Wiseco Performance CRF450 was aided by the Yoshimura RS- 4 titanium exhaust system. The MXA wrecking crew has spent extensive time testing this exhaust, and it is one of our favorite systems for the CRF450. It punches up the powerband, particularly in the midrange, and when coupled with the EFI Controller, it is a match made in heaven. Clutch: Another noticeable improvement on the Wiseco Performance CRF450 compared to A huge problem area on the 2009 and 2010 CRF450 is the stock four-spring clutch. Wiseco makes an excellent six-spring clutch that is far superior to the stock unit.