2007 Suzuki RM-Z450

2007 Suzuki RM-Z450: The Final Carburetted First-Generation 450

The 2007 Suzuki RM-Z450 was an evolutionary version of Suzuki's first-generation 450 four-stroke motocrosser rather than an all-new machine. By its third model year the basic RM-Z450 formula was well established: a 449 cc DOHC four-stroke single, Keihin FCR carburettor, compact four-speed transmission, aluminium twin-spar frame and fully adjustable Showa suspension. Suzuki concentrated on refining a package that had already proved highly competitive rather than replacing it.

The early RM-Z450 had earned its reputation almost immediately through factory racing. Ricky Carmichael had taken the new Suzuki 450 to a dominant AMA outdoor motocross championship in its debut era, giving the RM-Z450 instant credibility against established four-stroke rivals. By 2007 the motorcycle was no longer an experimental newcomer but a proven member of Suzuki's motocross range.

For owners, one of the defining features of the 2007 bike is its Keihin FCR40MX carburettor. Electronic fuel injection was about to change the RM-Z450 dramatically, making 2007 the final model year before Suzuki's landmark move to fuel injection for 2008. Correct jetting, accelerator-pump operation and general carburettor condition therefore remain important on surviving examples. MXOwners' carburettor reference and replacement information can help when researching the fuel system.

The chassis continued to use Suzuki's aluminium twin-spar design with Showa suspension providing approximately 310 mm of travel at both ends. Correct fork servicing makes a noticeable difference on these competition machines, with Suzuki specifying SS-05 or equivalent fork oil. Owners rebuilding the front suspension can also consult the MXOwners fork oil reference for additional servicing information.

The 2007 RM-Z450 is particularly interesting today because it closes the opening chapter of Suzuki's 450 four-stroke story. The following 2008 model brought one of the biggest technological changes in production motocross when Suzuki introduced electronic fuel injection to the RM-Z450. That leaves the 2007 as the last of the original carburetted RM-Z450s: mechanically straightforward by later standards, closely connected to Suzuki's early four-stroke racing success, and an important stepping stone between the first 2005 machine and the fuel-injected generation that followed. Owners sourcing components should confirm the exact model year rather than assuming later RM-Z450 parts interchange, with the MXOwners parts finder useful for researching replacement parts.