DIRT BIKE 450 SX-F QH (QH-090)
Detailed Product Description
Engine
- 449cc liquid-cooled, four-stroke single with titanium valves
- Revised engine tuning provides stronger low-through mid-rpm performance, with the same championship winning top-end rush
Top End
- High-acceleration cams with revised timing help the engine rev more quickly
- Camshaft lobes and tappets feature a soft-nitride surface treatment for long wear and high-rpm reliability
- Hand-finished surfaces of the polished intake ports improve intake efficiency at all rpm
- Lightweight titanium 36mm intake and 31mm exhaust valves and aluminum valve retainers reduce reciprocating weight for reliable valve control at high rpm
- Double valve springs help ensure stable valve operation
- Screw-type automatic cam chain tensioner with oil pressure spring
- Revised ignition timing helps boost power
- Low-friction coating on piston skirt
Bottom End
- Crankshaft, rotor mass centralization, oil circulation, and ignition timing have been carefully examined to help ensure ideal engine braking characteristics
- Crankshaft and connecting rod are sintered for additional rigidity
Starting
- Features highly reliable auto-decompression system; the dual-weight centrifugal decompression system fitted to the exhaust cam eases starting, and its simple construction helps to ensure reliability
- Hot start system gives quick starts when the engine is hot, and the hot start lever is unitized with the clutch lever
Exhaust
- Larger 41mm titanium exhaust header for increased power
- Tapered exhaust pipe joint helps increase ultra-low rpm power.
- Titanium exhaust pipe heat shield
- Silencer uses long-fiber packing for lower maintenance
Cooling
- High-capacity Denso radiators deliver superior cooling efficiency
- Slim radiators feature tightly packed cores and fins designed to enhanced heat dispersion
Shifting
- New 5-speed Transmission offers better choices for dealing with tough rhythm and tight technical track sections
- New ball bearing shift lever for smoother shifting
- Revised ratchet-type shift mechanism for smoother shifting and a more positive feel
Frame
- Frame is wider at the rider's ankles, for better grip and narrower around the seat for a slim riding position and enhanced maneuverabilit
|