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Manager of Motorcycle Sports at American Honda, Sam Mishima, explained the failure, “Clearly, we’re very disappointed by what happened at the Motocross of Nations,” said . “The factory KYB shock on our bike uses a cup-shaped spring collar with a slot where it slides over the shaft, and when the mud packed on the bottoming bumper during the first moto, enough force built up to shift the collar out of place. We used this same setup the entire AMA Pro Motocross season, including at muddy races like Unadilla, but this was the first time we experienced this issue.
“We replaced the entire shock for Cole’s final moto, but the same problem occurred again. Normally with issues like this, it’s difficult to even recreate them again, so the fact that this problem occurred twice on the same day suggests there was something particular about the Matterley Basin track layout and/or the consistency of the mud that created the perfect conditions for the problem. Honda customers should know that the retaining system on the production Showa CRF450R shock is different; in fact, the system is the same as that on the factory Showa shock used by our MXGP counterparts at Team HRC, whose bikes didn’t experience this issue at the Motocross of Nations. Obviously, we’ll look into this along with KYB and address it for next season, but in the meantime, we offer our sincere apologies to Cole, and to American motocross fans for the fact that Team USA’s results were so significantly impacted by this issue.”
Addendum: Honda added this extra note: “KYB would also like to acknowledge the impact the failure had on the U.S. effort and offer their apologies to the MX community. Countermeasures and design updates are currently being instituted to insure this type of situation does not happen again. KYB adds that only factory KYB-issued parts for HRC factory bikes and race teams are affected.”