OK, so here we go with the long awaited part two of the 2019 RMZ450 “NEED ONLY” build. As we stated before in part one, this is a damn good bike that just needs a few improvements. So, in this part of the build we focused on trying to find a little more power, improving clutch feel and durability, and just some bolt on parts to add a little more “NEEDED” comfort.
What: High compression Pro Circuit piston
Why: Simply stated, the bike needed more bottom end power
Conclusion: Once I picked up the bike from Pro Circuit, after they added the high compression piston, I couldn't wait to get it to the track and see the result (we are able to run pump gas as the compression ratio allows us to). I was surprised that such a small change could make a big difference. The power was improved in all aspects of the power band, not just bottom end delivery. On bottom end (with stock piston), the stock power was too mellow and the recovery characteristic was poor especially when the track is ripped deep. This mod improved bottom end torque and recovery was vastly improved when I was in the wrong gear. If I am being picky, I still want a little more RPM snap, but we may be able to get that with ignition or different mapping (this may be in part three). Surprisingly, the biggest improvement to the power was through mid to top end pull. I feel like anytime I grabbed third gear, this bike had a smooth yet very noticeable meatier pull up through the top end (compared to the stock piston). Overall, this Pro Circuit HC piston took a weak stock powerband and made it fun to ride with more than enough power to clear obstacles out of corners or pull you out of deep corners, but kept the rideability and rear wheel traction high. To me the is a “MUST” on this bike to improve excitement factor. Note: Running white coupler for best feeling on track.
What: Hinson clutch (outer basket, inner basket, pressure plate, fibers, plates, heavier springs, and clutch cover)
Why: To improve overall durability and get rid of the vague feeling at the clutch lever
Conclusion: The Hinson family has been making top quality clutch components for as long as I can remember. In 1997, when McGrath made the switch to Suzuki, he enlisted Hinson to solve his clutch problems with that model, not factory Suzuki. Immediately the feel at the clutch was more positive and less vague before I even made it onto the track. Once I rode the bike on the track, the Hinson clutch took the improved power that we got from the piston and transferred that to the rear wheel. The stock mushy lever feeling was gone and a slightly stiffer firm feel replaced it. However, it wasn’t a “Honda hard pull” feel, just slightly firmer/more positive than the stock Suzuki pull. I have been riding with the Hinson clutch for over a month and that feeling hasn't changed one bit. The Hinson durability is second to none and the improved feel was welcomed. Editors Note: Also just to give you guys, the reader, more insight on Joe’s riding technique, he is known to be a clutch destroyer. Joe is very hard on clutches and to say that a clutch has made it over a month without changing plates says something.
What: FCP Engine mounts
Why: Chassis felt a bit rigid on corner entrance, transitioning, and exiting choppy corners
Conclusion: I couldn't remove that small insecurity when entering corners, no matter what I tried with the suspension. I figured it had to be due to the stiffness in the chassis and not the suspension. Kris Palm approached me at Milestone and bolted on his engine mounts for me to give it a try. Keefer told me that some of FCP mounts have made a differene in the past, so I was curious to see what they would do to this chassis. Immediately the mounts got rid of most of the stiff bound up feeling of the chassis and allowed it to settle entering corners, stayed planted transitioning through the middle part of the corner, and allowed the suspension to absorb any acceleration chop while keeping the rear wheel planted under acceleration. Another improvement from a simple bolt on part that gave me that secure feeling to allow me to carry my momentum through corners and push the bike a little harder.
What: Pro Taper (bars, grips, throttle tube, front brake lever, clutch perch/lever, chain, sprockets, and hour meter)
Why: To achieve more comfort, adjustability, and durability
Conclusion: Bars - Once I found the right balance of bar height and bend while sitting and standing, I was happy with the SX Race bend.
Grips - Working my full time job doesn't allow me to ride as much as I would like. Having the right grips are key and the soft compound 1/3 waffle gave me that cushy feel, allowing me to ride all day with no issues and the grip was excellent.
Throttle tube - The stock plastic throttle tube had a sluggish/slow feeling to it so when we replaced it with the aluminum tube the throttle had a lighter, snappier feel. Plus it obviously is stronger and more durable in a crash.
Front brake lever - In addition to looking great with its black color and having a cool Pro Taper cover/shield, the XPS Lever offered great adjustability with the dial to adjust reach and its multi directional folding capabilities kept it from breaking or bending in a crash.
Clutch perch and lever - The Profile perch and lever offered the same great looks as the XPS front lever, friction free feel, quick adjust star to adjust clutch play, and a nylon sleeve to allow the perch to pivot in a fall. Additionally it folds in almost all directions further protecting it in a fall and the reach is also adjustable.
Chain and Sprockets - I kept the stock gearing ratio but, opted for the black Race spec front and rear sprockets which gave me increased durability and looks. The Pro Series 520 mx chain gave me that cool gold chain look with minimal stretching and longer lasting chain life.
Hour meter - The wireless hour meter was literally the easiest part I've ever applied to a bike. Peel and stick, then hit the button for info. It works off of vibration (eaaaaaaasyyyyyyy Keefer) while the bike is running, which led to a few complaints of additional time being added during transport. I live on a dirt road roughly 2 miles from pavement and i have had absolutely zero issues with this.
Overall I'm happy on this build, as Keefer mentioned, the whole point was to take a bike that consistently finishes towards the rear in the shootouts and show how great this bike can be with a few key improvements. I truly enjoy riding this bike and feel a confidence i've been missing since those years where I rode all the time. For the average guy, who may only get to ride once a week or less, to be able to hop on his bike and feel comfortable going fast is priceless. I feel we were able to achieve just that and hopefully this build will help you get that same feeling. Thanks for reading and stay tuned, i have a feeling this build may not be done yet.
Joe Oehlhof
14 year professional motocross racer
Finished 16th in points in 2005 in 450 class
Made every main events in 2005
Best 125 SX finish was Pontiac with a 4th Place 1999
Rode for AM Leonard KTM, Team Subway Honda, WBR Suzuki