Vortex Rear Sprocket, Aluminum V4, Style 642A (520)

Sprockets set your gearing. One tooth fewer at the front, or a couple more at the rear, makes the bike pull harder out of corners and lifts the front sooner, at the cost of top speed and higher revs on the highway. Going the other way calms it down. Worn sprockets have hooked or pointed teeth and will wear out a new chain quickly.

Stock photo: it shows a Style 435 V4 sprocket with 48 teeth. Vortex machines each V4 to its style's hub and tooth count, so Style 642A may look different.

Fits as a 520 conversion on the Yamaha YZF-R6

• Precision-machined from high-strength 7075-T6 aluminum
• 10-15% Lighter than CAT5
• Excellent concentricity for smooth, quiet operation and efficient power transfer
• Manufactured in the USA
• Model-specific: check the fitment list for your bike

Fits

Every tooth count of this rear sprocket fits the bikes above. Choose the stock count to keep your gearing, or a different one to change it.

A bike marked (520 conversion) takes this sprocket only once its final drive is converted to 520 chain, with a matching front sprocket and chain.

Changing tooth counts changes your speedometer reading on most bikes, and may need a different chain length. Replace sprockets and chain together.