BritIron Classics - Building Complete Norton Commando Engines with Modern Manufactured Components

At BritIron Classics, a subsidiary of Italianiron.com, we continue to have a great deal fun working on the formidable Norton Manx and twin cylinder racers like the Norton Commando & Dominator which is where I initially "cut my teeth" participating in period racing such as BOTT. We are so honoured to share our enthusiasm and collective expertise with racers and passionate builders of these iconic British motorcycles worldwide! Through our affiliation with the race engineering experts at Molnar Manx in the UK, we continue to offer the industry's highest quality complete engines, engine spares, bodywork and chassis racing components for these British machines. If you have ever dreamed about building an enhanced version of the original Norton Commando engine that is manufactured off of the original factory blue prints with significant enhancements or "fixes" to problem areas of the original components, with superior metallurgy and with more sophisticated manufacturing processes, then that time is now!! Newly offered is our heat treated aerospace aluminum Norton Commando engine head in conjunction with our very popular aluminum alloy cylinder barrel, chrome-moly steel engine crank, and our heat treated aluminum alloy engine cases. Shown below is our new 2 valve Commando head but the Norton engineers did draft a 4 valve Commando head like they did for the Manx engine. Stay tuned.

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It has been the goal of this effort to fulfill the best of the original Norton engineer's design goals for the early Norton Commando engines. However there were weak spots found over time when used that needed to be fixed. As a result and on offer is our new and enhanced Norton Commando cylinder head for 750 cc and for 850 cc engines. These engine heads are manufactured by Molnar Manx in the UK in association with John Snead here in the US who had acquired the complete "patternwork" for these engine heads. These Norton Commando heads are machined using fully heat treated aerospace spec aluminum alloy castings on 5 axis CNC machining centers that include the inlet ports which have been subtly modified to improve the support of the inlet guides. The exhaust ports are "as cast" originally but are "D" shaped in line with the best of current thinking. The Seats are Moldstar 90 (beryllium free copper) and the guides are aluminum bronze 630. The Inserts have been fitted for the 3 downward facing studs that screw into the head and those studs have been changed to UNC/UNF threads (originally BSF/26tpi Cycle) to facilitate the use of 12 point sleeve nuts to make the task of tightening the head a wee bit less difficult. These 3 studs and sleeve nuts are included with each head. All other threads are manufactured identical to the original so that all standard hardware can be swapped over. 

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We have been experiencing great success in the sale of our aluminum barrels made for the Norton 850 and 750 Commandos. These barrels are available in a broad range of applications for the Norton 650 cc, 750 cc, 850 cc and for our 920 cc, and 1000 cc engines as well. These Norton twin cylinder barrels are cast in fully heat-treated LM25TF aluminum alloy. They have deeper, thinner fins than than other barrels as we believe that it is worth that extra effort to achieve superior cooling. Additionally, our barrels are visually closer in appearance to the original Norton iron barrels in an effort to be more period correct. They also save around 5kg or over 11 pounds in weight!! Other options are Nikasil up to 850 cc, head bolt kit and barrel through bolt Kit. I am using our Norton Commando 920 cc barrel on our Norton JPN rep racer. in addition, we will be using longer Carrillo rods that are 6.400 inches long or .525 inches longer than stock. This increase in rod:stroke ratio creates a more ideal ratio, in our opinion, of 1.83:1 over a "stock" ratio of 1.67:1 when combined with 81 mm light weight pistons. Our intention with this longer rod and light weight forged aluminum piston kit is designed to pursue greater performance with less vibration as the pistons are 2/3 the weight of stock items. JS Motorsport, for example, has achieved a gain of approximately 7 more HP on the dyno by switching to this kit. We will provide our own dyno run results after installation. 

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We have also had great success in offering newly manufactured engine cases for Norton Commando engines. Attention was given to strengthen those areas where the original items were commonly known to be prone to breaking such as to the top side of the timing case cavity and the upper areas of the drive side. These technologically enhanced engine cases are cast in fully heat treated LM25TF. Then they are machined on state of the art 5 axis machines to provide a product of enhanced quality that has not previously been available to the road racer or to the Norton enthusiast. These Norton Commando engine cases are designed to factory specifications following the original 850 and 750 Commando blue prints. A 1000 cc version is available but know that our 1000 cc is a unique build and requires specialty items such as our engine cases, specialty crank, 83 mm barrel and our specialty head. We will be building a Norton 1000 cc Commando in a Dunstall Norton chassis that will soon be on the bench and we will publish the build as it progresses. It is our hope as a result of our offerings, that it will help you to become immersed in the history, the passion and the early racing technology of these amazing British racing motorcycles. Let us "Fuel Your Race Passions" to keep the sport of Vintage Motorcycle Racing alive and well!