Description
For two-strokes, 104–122 °F coolant temp is the sweet spot for max power. Push past 140 °F and your CR500 is bleeding 1% horsepower for every degree hotter. This is where the MSV Racing CR500 “OptiFlow” Cooling Power Pack shines! Proven to cool up to 18* better than the competition!
"Jason’s Impeller design keeps both my CR500 and KX500 cool in the AZ Deserts. A temp gun on the radiators shows a considerable cooling over stock."- Douglass B.
MSV Racing OptiFlo™ “phi” High-Volume KX500 Impeller
Cooler Temps. More Power. Unmatched Flow.
If you’re serious about performance, the MSV Racing OptiFlo™ “phi” HV Impeller is a must-have upgrade for your KX500 cooling system. Designed with precision, tested under race conditions, and proven to outperform every other impeller on the market — including Frank’s MX, AS3, and Mino.
3 Ways to Improve KX500 Cooling — Only One Works
Bigger radiator area? Not an option. The KX500's tight shrouds limit size increases, and thicker radiators only delay overheating. Cooler air? You're at the mercy of ambient temps — no control. - Increased coolant flow? Now we’re talking. That’s exactly where the MSV “phi” impeller dominates.
Engineered for Results:
- +1.2 GPM more coolant flow vs. OEM & aftermarket units
- Up to 18°F drop in head and coolant temps
- Golden Ratio vane design (φ) = optimized flow efficiency
- Precision CNC’d from 7075 T6-511 Aluminum – stronger, lighter, and built to last
- Closer impeller-to-housing tolerances for maximum hydraulic performance
- Tested on flow benches and real-world MX race conditions
Why It Matters:
More coolant flow = faster heat extraction = cooler engine temps = more reliable horsepower. With the “phi” impeller, your engine stays cooler longer — giving you the edge whether you’re tearing up GNCC, MX, Supermoto, Hillclimb, Sand Drags, or tight single track. Don’t let heat soak kill your power. Build a more efficient engine with the MSV Racing OptiFlo™ “phi” Impeller — and trust the only company that shows you the data to back it up.
Includes:
- Billet 7075-T6 OptiFlo™ “phi” Impeller
- High-quality H₂O pump cover gasket set
- Easy install. Big performance gain.
COMPARE BEFORE YOU BUY:
Frank's MX, Mino, and AS3? Same oversized impeller with a spacer. MSV’s “phi” Impeller? Completely engineered from scratch for the KX500's unique cooling demands.
Trusted by Racers. Proven on Track.
Join the riders who’ve dropped temps, freed horsepower, and run at the front — with MSV Racing.
Fitment