Originally Posted by johnnywalker
got me a 66cc engine kit and it said it comes with the 415 chain . but it looks just like bike chain . is that what it should look like or should it be bigger . i've seen some that have some bigger chain on them . but can't find the stuff . anybody ? thanks ....
It's not bike chain.
ALL these chains are 1/2" pitch (the distance between pin centers of one link). The differences are in tooth width, and in the chains' roller outer diameter.
Roller chains are specified by pitch, roller diameter (the circle pieces around the pins) and roller width.
#40, #41 are ANSI sizes. #415 and #420 aren't (I think) but they are still fairly-standard.
Bicycle chain is the same pitch and roller diameter, but is narrower-tooth than #40 chain. All the industrial chains above will fit on a bicycle sprocket (with different degrees of side-to-side looseness) but the bicycle chain will not fit on any of the industrial sprockets.
Bicycle single-speed cruiser chain is the widest bike chain, at 3/16" wide teeth.
Other multi-speed bike chains are even narrower: they use metric sizing, but the 11-speed chains are way down around 1/16" wide.