What do all the numbers mean regarding motorcycles chains?

Gordy's chart is correct for sizes, etc... but what do the numbers mean?





400 series chain, that is 4 X 1/8'; which equals 1/2'; pitch chain(length between pins).


500 series chain, that is 5 X 1/8'; which equals 5/8'; pitch chain(length between pins).


600 series chain, that is 6 X 1/8'; which equals 3/4'; pitch chain(length between pins).





The second two digits refer to the width of the chain.





420 chain has a width of 2.0 X 1/8'; = 1/4';





525 chain has a width of 2.5 X 1/8'; = 5/16';





630 chain has a width of 3.0 X 1/8'; - 3/8';





There are decimal and metric numbers that are sometimes cited, but the universal rule for both pitch and width are that they are multiples of 1/8';.





So I just bought some 530 X 110 chain for my bike. That means the chain has a pitch (link length) of 5/8'; and width of 3/8'; and the overall length of the chain is 110 links.





btw - you count the links by the number of inside and outside links including the master link (if that is not confusing enough?).





The idea is that when you buy a chain the pitch and width must match the sprockets on your bike. The length must also match the number of links of the chain you are replacing.What do all the numbers mean regarding motorcycles chains?
Chain Size Chart


Chain Size / Pitch / Inner Width roller


415 - 1/2 - 3/16


420- 1/2 - 1/4


520- 5/8 - 1/4


525 - 5/8 - 5/16


530 - 5/8- 3/8


630- 3/4 - 3/8


219 - .306 - .183