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AMSOIL vs. Mobil 1

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Mobil 1 MX4T Motorcycle Oil vs. AMSOIL Formula 4-Stroke 0W-40 Synthetic Motor Oil - Dyno Test and Comparison

AMSOIL Formula 4-Stroke Synthetic Motor Oil is specially formulated to provide serious protection and performance in recreational four-stroke motors, including ATV’s, outboard motors and motorcycles. With a broad 0W-40 viscosity rating, AMSOIL Formula 4-Stroke is ideal for use in both hot and cold temperature extremes. As an SAE 40 motor oil, it protects hot operating, hard working four-stroke motors, while its SAE 0 rating ensures excellent cold weather starting and quick post-startup lubrication in the coldest temperatures.

AMSOIL Formula 4-Stroke Synthetic Motor Oil’s formula contains no friction modifiers. This formulation is ideal for four-stroke ATV’s, outboard motors and motorcycle engines, ensuring dependable starting, smooth running, improved fuel efficiency, desirable stall speeds and clutch compatibility.

AMSOIL Formula 4-Stroke Synthetic Motor Oil provides superior shear stability and resistance to vaporization. Engine wear, oil consumption, heat and emissions are kept to an absolute minimum.

The high-temperature operation of four-stroke engines often leads to the thermal degradation and oxidation of conventional oils, leading to the formulation of deposits, sludge and varnish. However, the superior oxidative and thermal stability of AMSOIL Formula 4-Stroke Synthetic Motor Oil inhibits the formulation of varnish, deposits and sludge so equipment runs clean in high-stress, high-temperature conditions.

AMSOIL Synthetic 0W-40 Formula Four-Stroke Oil

AMSOIL 0W-40 synthetic motor oil for recreational four-stroke motors, including ATVs, outboard motors, motorcycles and other equipment requiring a four-stroke engine oil.

Formula 4-Stroke Synthetic Motor Oil provides superior performance in both hot and cold temperature extremes, offering the following benefits:

  • Superior shear stability
  • Resists vaporization
  • Inhibits formation of sludge and varnish
  • Ensures dependable starting and smoother operations
  • Improves fuel efficiency

Product Code AFF

AMSOIL Formula 4-Sroke Synthetic Motor Oil provides second-to-none protection and performance in Yamaha, Suzuki, Honda, Mercury, Kawasaki, Arctic Cat, Polaris, Nissan and Bombardier motors and transmissions specifying 0W-40, 5W-30, 10W-30 and 10W-40 viscosity grades. AMSOIL Formula 4-Stroke Synthetic Motor Oil is also safe for use in wet or dry sumps and is recommended for manual or automatic clutches and with clutch plates in ATV’s and motorcycle transmission. Drain AMSOIL Formula 4-Stroke at manufacturer’s recommended intervals.

AMSOIL Dealer and Motorcycle Racer – Keith Royle
I switched from Mobil 1 MX4T 10W-40 Motorcycle Oil to AMSOIL Synthetic 0W-40 Oil.

The graphs below show about a 1 hp and .5 lb/ft of torque gain with the AMSOIL.
Mobil 1 MX4T 10W-40 Motorcycle Oil vs AMSOIL Formula 4-Stroke 0W-40 Synthetic Oil
AMSOIL 0W-40 Synthetic 4-Stroke Oil vs Mobil 1 MX4T 10W-40 Oil
I also took temperature readings off of the clutch cover, and both side cases and discovered that those temps dropped an average of 10 degrees or more with the AMSOIL installed. Temperature readings were taken using a Snap-On infrared heat gun pointed directly at these components.

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