• Reed Valve Breather | Stop The Leaks

  • Reed Valve Breather | Stop The Leaks

  • Reed Valve Breather | Stop The Leaks

  • Reed Valve Breather | Stop The Leaks

 

The Norton twin cylinder engine creates a serious amount of pressure in the crankcase as the motor spins.  Over the years the factory attempted several methods to reduce this pressure – from a timed breather off the end of the cam on earlier motors, to an outright crude straight pipe from the timing chest on later 850s.  While their intentions were good, none of these designs could effectively keep up with a pumping parallel twin motor at high revs.

This Reed Valve Breather effectively releases pressure from the crankcases on the down stroke while preventing air from returning the motor on the up stroke, creating a negative pressure situation which can eliminate leaks and boost performance.  NYC Norton is the exclusive dealer for this beautifully designed part by Comstock Engineering.  This breather fits all Commandos that have a large sump screen on the bottom of the motor and installs in minutes with no permanent modifications necessary.  Screw it in, plumb it up, and go!

 

No engine we build leaves our NYC Norton shop without a good breathing setup.

 

(Note: Commandos built on or before 1971 utilize a crossover frame tube under the motor which, on occasion, can prevent installation of this breather. Please email info@nycnorton.com if you are unsure of compatibility)

 
 
 
 

$289.00 for Reed Valve Sump Breather

$9.00 for low profile blanking plug of stock breather (state year of bike)

We don’t have a shopping cart feature on our site, but gladly take PayPal or major credit cards
Please email your order (include your shipping address) to: info@nycnorton.com
We’ll return an invoice with details.