Chains

We sell both KMC and SRAM chains. SRAM are a larger and more well known company but KMC's chains are also of excellent quality and in many cases available at lower prices. We use chains from both manufacturers on our bicycles and we find they both work very well.

Note that all bicycle chains have a half inch (12.7 mm) pitch. i.e. the length of each link is 12.7 mm. However, the width of chains varies. Interior width is 1/8th inch for traditional single speed, hub gear, track and BMX bicycles. 3/32nd inch is normal for a bicycle with derailleur while 9 speed and above chains have an interior width which is even smaller at 11/128th of an inch. Some modern single speed bicycles, particularly those with Shimano hub gears, use 3/32nd inch chains instead of 1/8th inch.

Don't try to use 3/32nd chain on a bicycle which has sprockets intended for 1/8th inch chain as narrower sprockets are required for the 3/32nd inch chain.

Chains for 9/10/11 speed derailleur systems are progressively narrower on the outside. While there should be no problem with using one of the chains intended for higher numbers of gears on a bicycle with fewer gears, except that it will likely cost more, the opposite is not true. A gear intended for a 9 speed derailleur system may not shift correctly on a bicycle with a 10 speed derailleur.

To simplify: it's best simply to choose chains which are intended for the number of gears that you have. The manufacturers make a range suitable for each gearing setup, choose between these according to price, appearance and likely durability (anti-rust options can improve durability). While low weight chains may make a slight difference in a race they won't make any difference in the time it takes to get to work or to bring home shopping.

Chains increase in length with use and this causes them not to correctly fit the sprockets on which they are used and to cause wear on those parts as well. Chains don't actually stretch, but the bearings within them wear due to use and this is aggravated by grit getting inside. Chain manufacturers recommend cleaning the chain and checking for elongation every 500 km if you ride in clean and dry conditions and every 150 km if you ride in muddy conditions. We sell a suitable tool. We also sell chaincases which can prevent the chain from becoming dirty and greatly increase its life.

Many rather expensive oils are sold for lubrication of chains. It's more important that the chain is kept oiled and clean (the oil should be on the inside, not on the outside to collect dirt) than which oil you use.