cNw Services

Norton Commando Engine & Transmission Rebuild Services

For those who are re-building their own Norton Commando motorcycle, we now offer complete motorcycle engine rebuilds and transmission rebuilds. This service is offered on a limited availability basis that is keyed to our full cNw custom motorcycle rebuild scheduling. It must be noted that these engine rebuilds and transmission will be done to the same  specifications (cam choice is the only exception), with the same high level of detail and finish, and with the same list of optional extras as is available on cNw complete Norton motorcycle rebuilds.

These are “total” rebuilds in every sense, both mechanically and cosmetically. Since every machine goes through the same exacting process of machine work, parts replacement, upgrading, and detail finishing, we are able to offer this service at a standard base price.

A 2023 complete cNw engine rebuild is $ 6,895.00

A 2023 complete cNw transmission rebuild is $ 1,195.00

Note: The base price assumes that all major components are serviceable or repairable. Replacement parts are at extra cost. Speak to us for any questions. See the highlights that follow and note the comprehensive list of standard features. This is the cNw difference.

There are two build series per year. The engine/transmission needs to be at the shop on or before the 1st of the start up month in order to make it into the build series.

September – April/May

March – October/November

Contact us for availability and the schedule a rebuild on your engine or transmission


Motorcycle Engine Rebuilds – here’s what’s included:

cNw Norton Commando Engine Parts:

  • New WEB camshaft
  • New high quality, US made, rod shells
  • New crank and connecting rod hardware
  • New Superblend main bearings on both the drive and timing side, regardless of year engine
  • New cNw/ARP stainless steel crankcase hardware
  • New cNw/ARP stainless steel engine to cradle mounting hardware
  • New cNw/ARP stainless steel head fasteners, complete set
  • New cNw stainless steel rocker spindle covers and hardware
  • New CNC machined (looks like the original but with a superior finish) billet aluminum valve covers
  • New stainless steel valve cover studs and domed nuts
  • New Black Diamond valves
  • New bronze guides
  • New valve springs and insulators
  • New woodruff keys
  • New crankcase magnet is installed
  • New rocker arm thrust washers and springs
  • New mushroom head tappet adjusters
  • New pistons and wrist pins
  • New Total Seal gap less ring set
  • New cNw braided stainless steel overhead oil lines
  • New cNw/ARP barrel base studs and nuts
  • New factory gaskets and seals used throughout
  • New NGK spark plugs
  • New cam chain tensioner
  • New cam bushings as required
  • New billet aluminum ignition cover
  • New SRM, stainless steel pressure relief valve

cNw Norton Commando Engine Machine Work:

  • Barrel is “decked” for flatness
  • Barrel is heat cycled
  • Head is “decked” for flatness and combustion chambers equalized for volume
  • Barrel is precision re-bored and honed
  • Precision three angle valve seats are cut
  • Valve lifters are surface ground
  • Crankshaft is split, Magnafluxed, and turned
  • Tachometer drive seal modified to prevent leakage
  • Complete cNw/Comstock breather modification is done to both drive side and timing side case half
  • Oil drain return is modified in the timing chest
  • All covers are “glassed” flat for oil tight fit

cNw Norton Commando Engine Detail and Finish

  • All covers are, sanded then show polished and fasteners replaced with stainless steel
  • Cases are bead blasted, pressure washed and then media tumble finished
  • Barrel is ceramic coated in a high gloss, heat dissipating, black finish


Motorcycle Transmission – here’s what’s included:

cNw Norton Commando Transmission Parts

  • Both main shaft bearings and the seal are replaced
  • Lay shaft gets upgraded roller bearing
  • Quadrant and Camplate o rings are replaced with seals
  • Gear bushings are replaced as required
  • Shift linkage springs are replaced
  • cNw push rod seal fix is included
  • Kick starter shaft  and shift shaft get a seal upgrade
  • New stainless steel drain bolt
  • New stainless steel level plug
  • Modified gear shift stop plate
  • New factory gaskets used throughout
  • New inner cover studs are required
  • New polished cNw inspection cover with stainless allen bolts

cNw  Norton Commando Transmission Detail and Finish

  • Outer cover is show polished and installed with stainless allen bolts
  • Transmission cases are bead blasted, pressure washed and then media tumble finished


Motorcycle Engine & Transmission additional costs if required

A full evaluation of your project will be made before work begins. Speak to us if you have any questions or know of any deficiencies such as fin repair, exhaust thread repair, etc. Charges can be quoted for these or any of the following options and extras:

 Engine additional cost if required

  • Any heli coil installation required
  • Rocker arm replacement
  • Valve seat replacement
  • Exhaust thread repair
  • Head or cylinder barrel fin repair
  • Any damage to cases that will require welding
  • Any core parts that can not be used for the rebuild such as crankshaft, camshaft (core for re-grind), barrel, head etc


Transmission additional cost if required

  • Gear set replacement
  • Main shaft or lay shaft replacement
  • Shifter fork replacement
  • Kick start shaft or pawl replacement


cNw Norton Commando Engine Shipping & Delivery Terms

We require a $ 3,000.00 deposit when work starts on your engine. This initiates the rebuild process. The final payment is due when the engine is completed. Once the tear down and inspection steps have been completed, we will let you know of any extra work that is required.  All motorcycle engine and transmission rebuilds are warranted for defective parts and/or errors in workmanship. We include a comprehensive “build sheet” listing all work performed on your engine with appropriate specifications for your records and reference. Also included is a detailed break-in schedule and check sheet. This will guide you through those early critical miles and the required re-torque and valve adjustment rituals. (Records of these re-torque and valve adjustments are necessary for our warranty.)

When shipping the engine to our shop, use a common carrier and take great care to ensure that the engine/transmission is packaged properly. Break down to smaller assemblies (head separated from barrel) and ship in more than one box if possible. Insure for full value

When the engine is completed it will be returned to you in a metal crate. It will be insured for full value. Once you have removed the engine from the crate it will need to be returned back to cNw. We will cover the shipping expense for returning the crate to the shop. If the engine needs to be shipped to Alaska or Hawaii, a wood crate will be built for the engine. This is a one way freight and there will be an additional charge for building the wood crate

For any engine rebuilds outside the USA, please contact us for details in regards to shipping and handling.

To order and schedule your motorcycle engine and/or transmission rebuild, please    

contact us