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US FlagWednesday, July 24, 2024
Welcome to the British Motorcycle Chain Helper

When Vintage British Motorcycles were originally built, they typically used chain from a British company named Renold.  That chain was British Standard (sometimes called metric) 10B-1 rather than the "530" chain that is much more common today.  BTW, I'm not sure if it is European Standard or British Standard - depend on where you look or who you ask! 

In chains, links and pitches mean different things, but US and UK meanings and simply people interchanging them cause them to both mean the distance between the pins.  I'll use links from here on.

Motorcycle chain has several components:
  • The main portion of the chain, usually around 100 links long
    • Outer Plates
    • Inner Plates
    • Pins
    • Rollers
  • Master Link - These are used to connect the two ends of a chain together and include one outer plate with two pins permanently attached, a removable outer plate and a retainer.
  • Half Link - chains are always an even number of links without these.  Sometimes, chains can be purchased with a built-in half link, but they can be hard to find.  A removable half link lets you add one link to a chain so it has an odd number of links.
Motorcycles usually use 530 chain and sometimes 520.
  • 530 (similar to 10B-1)
    • 5/8" links/pitches/distance between pins (the 5)
    • 3/8" roller width (actually slightly wider than 3/8" and 530 is slightly wider than 10B-1)
  • 520
    • 5/8" links/pitches/distance between pins (the 5)
    • 2/8" (1/4") roller width (actually slightly wider than 1/4")
    • These chains were not strong enough when 10B-1 chains were standard on British bikes.  Modern 520 O-Ring and X-Ring chains are plenty strong enough.
    • For Norton Commandos, we have conversion kits to switch to X-Ring 520 chains.  This is a worthwhile upgrade!
If your sprockets are made for 10B-1, 530 chain will work with them; but, if they are made for 530 chain, 10B-1 might not work.  The length of the chain links is the same and the roller sizes are the same, but the width is slightly different.

530 chains come in Standard Duty, Heavy Duty, O-Ring, X-Ring and others.  Modern motorcycles use O-Ring or X-Ring chains as they require little to no maintenance.  Vintage British Motorcycles often cannot use anything but standard duty due to clearance issues and even ISO standard duty chains can be a problem, especially with the master link.

A common standard chain with the brand name Elite (and most others as well) measures 0.820" at the widest point and its master link measures 0.870" at its widest.  The chain itself is OK on a Norton but the master link can cause severe damage to a Norton 850 Commando as the pins will hit the inner chaincase sealing plates.  If the master link is installed from the outside in, its pins will hit the gearbox but probably cause no real damage.  Installing two gaskets between the engine and inner chaincase will sometimes let the master link barely clear the plates, but it's still quite dangerous.  The Norton 750 Commando with one gasket has about the same clearance as the 850 with two so it has an issue as well. Note: It appears that there two "Elite" chains. I'm told that the ones from Andover Norton are fine but the ones I bought from Wassell are definitely not, they are too wide. As far as I can tell, they are both made by IWIS!

Triumph Tridents, and probably other Triumphs have barely enough clearance with standard chain and not enough with heavy duty chain.

If you would like to study this subject in more depth, try these links:
Renold Chain Info

If you would like to completely resolve your Norton chain problem and nearly eliminate chain maintenance, you can install (or have us install) the cNw 520 X-ring chain conversion.  Click here for cNW or here for our cNw special.

Burlen, the parent of the AMAL Carb Company    The AMAL Carb Company     Tri-Spark, inovative electrical products for the Vintage British Motorcycle     Wassell, the 70+ year old suppliers of British Motorcycle parts     cNw has become a leader in bringing new parts and improvements to the Norton motorcycle market.
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