Britiron & Italianiron Classics, Product Post #5 Norton Commando Engine Bits & Fuel Tanks

Posted by Scot Wilson on


It has been said that at BritIron & Italianiron Classics, let us "Fuel Your Race Passions" is not just a slogan but a commitment, whether you are building a vintage TT racer for competition, a Ducati F1 vintage street bike or a classic Manx or Norton Commando racer. As a result, we are focused on and primarily committed to supporting the sport of Vintage Motorcycle Racing worldwide. Maintaining a quality offering is our most important goal. Our race spec items are race tested for quality, for assurance of structural integrity, for performance, for light weight, and for reliability. We also strive to maintain a "race team mindset" where we preserve the core of the machine but work to enhance performance and safety through the advances in available modern technology. As a result, we are extremely excited to offer a very comprehensive inventory of Norton Manx & Twin Cylinder hand-made aluminum fuel tanks that are guaranteed to fit properly.

In addition to our portfolio of Norton Commando fuel tanks, we can now offer Norton Commando engine racing spares. Shown below is our Norton Commando engine cases that started with a design from a set of Norton 850 Commando MK2 crankcases. From there we created patterns to manufacture these new "heavy duty" cases. Attention was given to strengthen those areas where the original items were commonly known to be prone to breaking! Specific attention was also given 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 as standard or in original 850 and 750 Commando specifications. 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, our specialty crank, and specialty head).

The three piece design of the Norton Commando crankshaft has been manufactured and used since the late 1980`s and it is now available to our customers but with the benefit of full CAD design and CNC manufacture.  We start with premium nickel chromium molybdenum steel and then machine the engine crankshafts on our range of CNC machines before hardening & tempering to 60 tonnes UTS. The separate flywheel is manufactured from the same grade of steel and held together with high tensile studs & nuts. Obviously, the lighter the crankshaft of a Norton Twin, the better the engine as demonstrated by improved acceleration and braking. The 89mm stroke cranks are just over 20 pounds (9.1kg) which is the lightest that can be produced whilst achieving our desired balance factor of 75% for rigidly mounted engines. If you are planning to mount the engine in an "Isolastic" chassis, the balance factor needs to be reduced to 52% & this should be notified at the time of ordering. Due to the manufacturing process, the dynamic balance is improved in contrast with standard OEM cranks. This positive result as it relates to the "balance factor", assumes the use of stock rods & pistons. At the moment, 89mm and 93mm (for 1000cc engines) stroke cranks are currently available. However, the range may be expanded in the future.

Shown below is a set of Aluminum Barrels for the Norton 850 and 750 Commando. In addition, we do offer barrels for our 1000 cc engine as well. These Norton twin cylinder barrels are cast in fully heat-treated LM25TF aluminum alloy. They have deeper, thinner fins than any other barrels on the market today. Whereas this design does make it more difficult to cast these barrels, 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 (11.023 lbs) in weight! The Commando engine barrels are produced on modern 5 axis machinery to precise tolerances and are truly the optimum barrels for your Norton twin cylinder engine. Options in bore size are: 83,81,77, 73, and 63 mm.

Additionally, any post regarding newly manufactured Norton Commando racing quality spares would not be complete if I did not mention our quality selection of OEM Norton items that are available through Britiron Classics. Whether you are restoring your Norton Commando with OEM items or are looking to upgrade your Norton with any of our newly manufactured engine bits or aluminum fuel tanks as discussed above, our expertise is at your disposal. Our objective is to help you find the most significant performance and safety enhancements to your vintage racer or streetbike. We also continue to offer Norvil race and street half fairings, windscreens and other bits for your Norton Commando racing variant. Contact me regarding your specific requirements at


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  • I am thinking about building bikes again, specifically Norton’s. I’m interested in what you had to offer Michael 303–9 95–5845

    Michael gallagher on
  • Great to see all norton bits
    Albie o donnell on

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