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IMPORTANT NOTICE: Due to increase in fraudulent orders the billing & shipping address must match when placing your order. Thank you for your patience and understanding.
IMPORTANT NOTICE: Due to increase in fraudulent orders the billing & shipping address must match when placing your order. Thank you for your patience and understanding.

Banshee 521 Supercub 10 mil Super Cub Big Bore Complete Top Bottom Assembly Kit

Sold out
Original price $4,939.99 - Original price $4,939.99
Original price
$4,939.99 - $4,939.99
Current price $4,939.99

  • 72x64cc Super Cub cylinder fully drag ported*
  • Wiseco custom 72mm forged Racer Elite pistons
  • Nitrite coated piston rings
  • Chrome plated wristpins
  • Circlips
  • Wristpin bearings
  • Crankworks +10mm billet stroker crank with 115mm rods*
  • Noss Machine billet Super Cub head
  • 29cc billet cool head domes
  • Maxload and TZ outer crank bearings
  • Transmission bearings
  • Shift cam bearing
  • Water pump bearing
  • Clutch pusher with bearing mod
  • 8 plate drag clutch assembly
  • Billet clutch basket
  • Complete gasket kit
  • Complete seal kit
  • Billet water pump impeller
  • Maxlock complete allen head stud kit
  • 12 point flange nuts, water jacket plugs, stud extenders
  • NGK spark plugs
  • Billet intake manifolds with boots
  • 41mm Genuine Keihin PWK Pro Series Carbs
  • K&N style hi flow air filters
  • Black pre-filters
  • Terrycable steel braided throttle cable - Comes as thumb unless you contact us and ask for twist
  • Moto Tassinari V-Force 4 reeds

Visit us online or in person from 7am to 4pm at 1538 Howard Access Rd, Suite A, Upland, CA 91786

Payments:  We accept all forms of payment – Cash, MC, AMEX, VISA, DISC, PayPal, Venmo, Cash App, among others.  Payment can be made online or over the phone or in person. 

Returns: Returns are accepted within the first 30 days as long as the order is sent back to us BRAND NEW, NEVER INSTALLED, 100% COMPLETE, AND IN THE ORIGINAL PACAKGING.  Any item returned after installation is not eligible for a refund.

 *Warranty:  This product is NOT DIY.  Over 99% of people in the world are not qualified to build an engine.  We ALWAYS STRONGLY recommend parts be installed by a qualified, experienced mechanic.  Warranty does not cover failure that is a result of improper installation, tuning, break in, or misuse.  For any warranty to be considered the part(s) in question must first be sent back to us for inspection.  We do not warranty parts based on phone calls, photos, emails, or another mechanic's assessment alone.  It is the responsibility of the person assembling and tuning the parts to make sure they work correctly. 

*While it is not required in order to maximize performance with this kit your top case should be match ported to the cylinder.  All Supercubs require the top case half to be bored for the cylinder.  When using stock cases, all +10mm cranks require trenching.  Finally, Supercubs are a high performance drag race engine and are intended to be used with 100+ octane fuel.

Feedback: Positive reviews and feedback are greatly appreciated.  We have changed the way we do business in response to customer concerns and receiving positive feedback when an order goes the way it is supposed to is a huge help.  If you do not feel we deserve positive feedback or reviews just contact us and we will do what is needed to help you feel as "positive" as possible about your experience.  To make it worth your while we will give you 10% off your next order for taking the time to leave us 5-star positive feedback.  That could be hundreds or dollars for 1 minute of your time!

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