2004 Honda RC51 Comparison

MotorcycleUSA Staff | July 29, 2004
Mitchell has plenty of experience racing the solid RC51.
Mike Mitchell found the RC51 to be a quicker turning machine than the 999S, but not as quick as the Mille Factory.

Up front, the fully adjustable 43mm inverted O–hlins fork performed well on the Mille, but out back we had a more difficult time dialing in the Ohlins rear shock. Because of the varying weights of our group, test riders over 175 lbs found the rear end swaying a little bit while navigating high speed turns. We adjusted the suspension accordingly, adding three full turns of preload, eight turns of rebound, and then added four more clicks of compression.

At that point the Aprilia stabilized and emitted much less movement from the rear end. However, the rear suspension action loosened up again by the end of day 2, especially for those of us with grand physiques. Roberti, who is no stranger to tuning suspensions, believes the Mille should be sprung stiffer to accommodate buffet-gorging Americans.

“The rear end was much better after the changes,” Roberti comments. “I think maybe you could put a stiffer spring back there and it would help. But after the changes, the bike turns in well and is very stable on the brakes. The front fork is a little stiff, but not enough to want to change it dramatically.”

The RC51 offers up a fully adjustable 43mm Showa cartridge fork that is complimented by a fully adjustable Showa shock. While the Showa components are definitely a notch down from the O–hlins sported by the other two competitors, we found them to work pretty good on the track. The RC has decent quickness into and out of corners while demonstrating the stability that we felt during the street portion of the test. Roberti believes there is too much front compression in stock form and subsequently he backed it out eight clicks. The changes to the front helped the front end work better and put the Honda back in the hunt.

2004 Honda RC51 Highs & Lows
  • Every component and piece of hardware functions beautifully
  • Most powerful Twin
  • Road going ameneties
  • $11,599 – way less than Aprilia or Ducati
  • Tall gearing saps power output
  • Lacks specatacular aesthetics
  • Brake fade after prolonged riding

While the RC51 steers pretty quick and holds its line well, it isn’t as quick as the Mille or as stable through the corners as the Duc. Suffice to say, Honda built a rock-solid, all-around machine for the track, despite weighing in at a hefty 456 pounds without fuel; 22 more than the Mille, and 14 more than the 999S.

The rear Showa shock began to lose rebound damping considerably when we rode the RC51 at high speeds on the bumpy Thunderhill surface. In an effort to keep the back end from wallowing, we stiffened up the rear like we did on the Mille. But the RC51 reverted back to the rear end dance by the end of the second day. It’s a phenomenon which didn’t surface during our street portion and gave us even more reason to appreciate the pricey, high-end O–hlins suspension.

MotorcycleUSA Staff