Yamaha calls their new YFZ450X the ultimate high performance tight trail sport ATV. Of course the newly designed hi-tech engine found in the YFZ450R is also used in the new X, no arguments there. And the good news doesn’t stop there for cross country riders. Yamaha could have just narrowed up the R and called it an X. Yes, the new YFZ450X is 46.1 inches wide compared to the R’s 48.8 inches, but they didn’t stop there. The new 450X also features a few key changes that should provide for an impressive ride out on the trail as well as the GNCC track.
The original YFZ was the first race-ready 450 sport quad. At one point in 2004 nearly every serious production ATV racer relied on their YFZ in order to be competitive. In 2009 Yamaha completely rebuilt the YFZ and the YFZ450R was born. The R excels in many situations, especially motocross tracks and sand dunes, but wasn’t just right for cross country applications. Enter the YFZ450X! It’s the latest evolution of Yamaha racing technology and it’s optimized especially for tight trail riding and GNCC racing!
Size Does Matter
It’s common sense, if you want to weave your way through narrow trees and trails you’ll want a machine that’s smaller in size. The new X takes care of that. This is accomplished through a new front end design and a 50 mm shorter rear axle. Accompanying those updates is a change in steering geometry specific to woods riding translating into less fatigue for the rider.
Optimized Suspension
Like we said Yamaha didn’t just narrow up the width of their 450R. The YFZ450X comes with a newly designed front suspension. The front A-arms are shortened 43.9 mm to 395.2 mm, which Yamaha feels is the optimal dimensions needed for tight cross country trails and race tracks. The front KYB shocks on the X are 426 mm long versus the 462 mm length of the YFZ450R. The easy to adjust damping goes unchanged. As a full package, the new suspension settings, A-arm design and trail track width allow the YFZ450X to soak up bumps while also allowing the rider great handling through tight, technical terrain.
The gravity-cast aluminum rear swing arm is matched to a fully adjustable 46 mm KYB piggyback shock affording the rear wheels 11 inches of travel and is identical to the rear end on the 450R.
Engine and Performance
The YFZ450X features the powerful titanium 5-valve DOHC liquid cooled single cylinder 449cc engine using the cylinder head and cylinder from the championship-winning YZ450F motorcycle. The titanium five-valve cylinder head comes with camshafts designed just for ATVs that hammers out superior low- to mid-range torque and pushes through to a high-revving, hole-shot grabbing top end.
Like its track-dominating brother, the technologically advanced 450X is also equipped with electronic fuel injection featuring a 42 mm Mikuni® throttle body, 12-hole Denso injector system and a Mitsubishi 32 bit ECU, which provides exceptional atomization of the fuel for maximum power, unrivaled throttle response and automatic altitude and temperature adjustment. For 2010, the YFZ450X receives a new FI setting specifically designed for those situations unique to technical woods riding. The system also includes idle speed control for easy, reliable startup. A stainless steel head pipe with a titanium heat shield and a new oval muffler provide maximum performance while keeping the YFZ450X well below recommended noise limits. A job well done if you ask us.
Cast Aluminum Frame
The new YFZ450X features the lightweight, no-weld cast aluminum frame exclusively from Yamaha and first introduced on the 450R. The frame’s high tension-steel bottom portion helps keep the engine as low as possible, centralizing mass for optimized handling. The cast aluminum frame is bolted together, rather than welded, for maximum durability. Frame rake is the same as the 450R at 11 degrees, which is up from 8 degrees found on the old YFZ.