The LL Chain Wear Tool – which stands for Linear and Lateral – lets you measure the wear of any chain accurately, without being thrown off by either the larger roller diameter of flat top chains or by the extra lateral demands cross chaining with 1x drivetrains puts on the chain.

SRAM drivetrains feature flat top chains with a roller that's .010″ (.254mm) bigger than any before it, which when measuring five links of a chain, can cause chain wear tools to under measure wear by .2%. When replacing chains with between .5% and .75% wear is standard, this margin can mean the different between replacing just the chain or the whole drivetrain if a worn chain is allowed to impact the rest of the components.

Meanwhile, cross chaining to get the full range out of 1x drivetrains will put extra wear on the faces of the rollers, over time degrading the shifting performance.

The LL Chain Wear Tool is your solution for both of these scenarios. It is machined with a V-shaped notch in which to locate the chain roller. This captures both sides of that roller, not just one, which leads to more accurate results since the measurement originates from the centre of the pin and diameter ceases to be factor. The tool is then flipped so it's easy to see where the holes line up with the pin, to measure the degree of wear from 0-2.5%.

On the other side of the tool, the lateral chain wear measurement process is clearly detailed on the surface, as is the linear measurement process.

For lateral measurement the chain must be taken off the bike, then the pin is lined up with the edge of the boss for consistency, while the chain is extended out for five links, bringing the end in line with the indicator holes marking from one to nine. It is then held vertical to see how far it sags, making it clear whether the wear is significant enough to affect shift quality, with anything below a six being unacceptable.

Over and above its special features, the LL Chain Wear Tool is fine tuned for more accuracy than the great majority of chain wear tools on the market. Most are made with a CNC laser cutter, and while high end lasers can produce parts with an acceptable tolerance, commodity level machines can double the error margin of a traditional tool to +/- .010″ (.254mm).

In line with their motto, “precision is our religion”, Abbey Bike Tools has instead machined their chain tool from a single block of 6061 aluminium in their CNC mill. It can hold tolerances as tight as .00025″ (.005mm) on critical features, so Abbey's margin of error is a scant .004%.

• A chain wear tool that measures linear and lateral wear with outstanding accuracy
• V-shaped notch negates impact of larger rollers, e.g. in SRAM flat top chains
• Lateral wear can be measured to determine whether it will impact shifting accuracy
• Process for taking both measurements is clearly denoted on tool itself
• Tool is tuned for just a 0.004% margin of error by being CNCed from one billet inhouse