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BPRATV will be closed on December 24th and 25th in observance of the Christmas holiday. We will have very limited operations from December 27th to December 31st for our annual cycle counts. Thank you for your patience and understanding. Additionally, we will be closed on January 1, 2025, for New Year's Day.
BPRATV will be closed on December 24th and 25th in observance of the Christmas holiday. We will have very limited operations from December 27th to December 31st for our annual cycle counts. Thank you for your patience and understanding. Additionally, we will be closed on January 1, 2025, for New Year's Day.

Banshee 421 Cub Complete Engine Assembly Service Engine Motor Building Your Bike

by BPRATV
Original price $3,999.99 - Original price $3,999.99
Original price
$3,999.99
$3,999.99 - $3,999.99
Current price $3,999.99
YOU ARE NOT LOOKING AT A BUILT ENGINE.  PHOTOS SHOW DIFFERENT AVAILABLE OPTIONS, BUT FOR THE LISTED PRICE YOU SEND US YOUR ENGINE AND WE WILL REBUILD IT, USING YOUR BOTTOM END AND THE FOLLOWING NEW PARTS:
  • 68x58mm 421cc Cub cylinder
  • Wiseco 573M06800 forged pistons
  • Nitrite coated piston rings
  • Chrome wristpins
  • Circlips
  • Wiseco wristpin bearings
  • Hotrods +4mm stroker crank with rods
  • Billet cool head
  • Billet cool head domes
  • Maxload and TZ outer crank bearings
  • Transmission bearings
  • Shift cam bearings
  • Water pump bearing
  • Clutch pusher with bearing mod
  • 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
  • Complete assembly
These are more parts that can be added that are not pictured:
Billet intake manifolds $130
35mm genuine Keihin PWK carbs, throttle cable, filters, and pre-filters $625
V-Force 4 reeds $225
Genuine OEM Yamaha flywheel $500 (Lightened for $100 more)
Genuine OEM Yamaha stator $500
Direct Drive lock up cover $399
New OEM stator cover $85
Parts polishing Price varies depending on extent of polishing

Lead time is 2 months from the date we receive your bottom end.  We suggest contacting us to discuss options prior to buying.  Everything is new in the original packaging.  We are an authorized distributor and the original manufacturer’s warranty applies*.  PRICES AND LISTINGS ARE SUBJECT TO CHANGE AT ANY TIME WITHOUT NOTICE.

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. 

STUD WARRANTY: If for any reason a stud fails during use, not installation, we will send an entire new stud kit.  No other parts or any labor are included, and it can not be converted to a refund or discount on any order.  Studs must be returned to us for inspection first. 

ALPHA CUB WARRANTY: If your Alpha Cub cylinder fails for any reason not related to installation, tuning, break in, or misuse we will fix the cylinder free of charge.  If it can not be fixed we will supply you with a new one.  It must be sent to us for inspection, and Millennium Technologies will determine if the cylinder is repairable.  WE DO NOT WARRANTY ANYTHING BASED ON WHAT ANOTHER MECHANIC SAYS IS THE PROBLEM.

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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