We're always been fans of the KTM 350 SX-F, but the latest generation (2023 and '24) has really taken a giant leap forward in power and handling. We were so impressed with it, in fact, that we included the 350 SX-F in our 2023 450 shootout and it fared quite well against the larger machines thanks to its superb handling and easy-to-ride, free-revving engine that makes the bike feel much lighter than a full-sized 450.
This year, we decided to see just how great we could make the 2024 KTM 350 SX-F, so we dropped it off with Jamie Ellis at Twisted Development (www.td-racing.com) to see what he could coax out of the engine. Twisted Development is legendary when it comes to building race engines, and we asked him to give us some great power gains without sacrificing durability so that we could ride and race the bike all year without worrying about a rebuild. TD ported the cylinder head, decked the head to raise compression, and performed a Newen CNC valve job. TD has a proprietary piston made to perfectly match these modifications and the top-end mods were completed by a TW high-flow venturi system in the intake. Vortex Ignitions are highly regarded in MX, and Ellis is a master of programming them. The package includes 10 TD maps, and we were stoked to learn that the stock dual map switch, traction control, and quick shift functions are all maintained. As delivered, our machine had the two most popular options pre-loaded into the handlebar switch; both with maximum power, but one with very little engine braking. Ellis does have a full-race performance package that includes diving into the lower end of the engine, but keeping our wishes in mind he opted to stop there. The Yoshimura RS-12 exhaust we've been running for the past year was maintained, as Ellis agrees that it is the best-performing aftermarket exhaust for the Austrian 250s and 350s. Due to the higher compression of the engine, VP Pro 6 Racing Fuel is required to keep the engine purring nicely.
For a suspension upgrade, we turned to enzo racing for what we feel is. the best handling upgrade you can make to any Austrian machine: the enzo KYB spring conversion kit. The kit converts WP front inner and outer tubes to accept the KYB AOS internal damping system. KYB AOS cartridge, rebound rod, compression base valve with standard caps, bottoming cones, springs and standard spring perches fit into the standard WP inner and outer tubes with the installation of the special machined conversion axle lugs by Technical Touch.
Out back, the standard WP shock was modified to complement the fork and valved for our test rider's weight and ability.
Twisted Development Cylinder Work: $1100.00
Twisted Development Piston: $475.00
Twisted Development High-Flow Venturi Intake $35.00
Vortex ECU: $1059.00
Yoshimura RS-12 Titanium Exhaust: $1299.00
enzo racing WP KYB Fork Conversion Kit: $1755 to $2173
enzo racing Shock Revalve: $220 plus parts and oil
www.td-racing.com
yoshimura-rd.com
enzoracing.com
13 дек 2023
