NEW UPDATED INTAKE YAMAHA BANSHEE 68MM BLASTER PISTON KIT FOR A BANSHEE
KIT INCLUDES: 2 PISTONS, RINGS, WRIST PINS AND CIRCLIPS.
Fits: 421cc (68mm bore, 4mill 115 rod crank)
443cc (68mm bore 7mill 115 rod crank)
465cc (68mm bore 10mill 115 rod crank)
**********A different thickness base gasket may be required depending on the cylinder your using.**********
The 68mm Blaster piston part#573M06800 is probably the most common piston used in a Banshee engine with aftermarket cylinders and stroker cranks. 1st thing that we never liked about the Blaster piston when used in a Banshee engine is the intake window design. The intake window on a Blaster piston is located very low on the skirt. When using this piston with a stroker crank (4mil, 7mil, 10mil) the low intake windows limits the amount of fuel flow. When the piston nears the bottom of the stroke the windows start to close off early.
The 2nd disadvantage we have seen with the windows being so low on the skirt is the strength of the bridge between the windows. Take a cub cylinder for example, which has a very thin intake rib. This thin rib is great for fuel flow but offers very little piston support. If you've run a cub cylinder for an extended amount of time you may have experienced the piston intake bridge cracking over time.
We had Wiseco make us a new piston with modifications to the old 573 series design. Wiseco uses the 573 slug to make our pistons.
First change was to move the intake windows higher up on the skirt so when the piston is on the downward stroke it will have a longer intake duration allowing a little more fuel and air to be pulled into the motor.
The second benefit from moving the windows up higher on the skirt is that the skirt is now stronger because the bridge is in the middle of the piston where there is more support and less stress.
Finally, with the windows located higher we were able to square the windows in shape and add a small extra dip in the bottom of the window which allows even more fuel and air to be pulled in on the down stroke.
All other aspects of this piston are identical to the standard 573M06800 Blaster piston and can be used with any engine combination that the Blaster piston is already used for.