Masterlink, #40/41 Standard Chain

1) A chain consists of steel pins that are rubbing inside of "steel tubes". These are commonly called rollers, but it is obvious that they do not roll. They just rub back and forth at very high speeds, under considerable load, pressure and heat. Squirting oil or even chain lube directly on these rollers does very little good unless the lubricant is given time to penetrate between each pin and the corresponding "tube". The lube must go along the side links on each side of the chain, then allow 8 to 10 minutes for penetration and evaporation before starting the engine to ensure the centrifugal force will not sling it away. The clutch sprocket and the main drive sprocket should be perfectly aligned so that they don't rub against the side links. Rubbing wears the teeth and ABSORBS HORSEPOWER.

2) All chains stretch over time. When the chain starts falling off the sprocket then it is time to move the engine forward or backward to take up the slack in the stretched chain. There are four bolts that hold the engine on the motor mount plate. Take an open-end wrench and a socket wrench (most likely a 9/16") and loosen the four bolts- pull back the engine until you take up the slop in the chain. Tighten the bolts back again but make sure the two sprockets are perfectly aligned with each other. You don't want the sprockets out of alignment because this will cause the chain to come off or wear the sprockets unevenly. Leave about a ½" of play between the top of the chain and the bottom don't pull the engine back where the chain is a tight as you can get it. A tight chain can cause the kart to move in neutral with no one in the drivers seat. A tight chain puts friction on the bushing or roller bearing, which could cause it to engage when the engine is idling. Make sure you properly retighten the motor mount bolts when the desired chain tension has been achieved.

Replace your chain when installing a new clutch or sprocket unless the chain is very new. If you are cutting a new chain make sure you don't cut it too short. You can always remove links but you can not add more than half a link.

If a replacement clutch or chain is required, determine the chain pitch size your machine is equipped with. Most American made fun karts and mini bikes use either #35, #41, #420 or #40 chain. Some chains have the chain pitch size stamped on the chain, some do not. Use the chart below as a guide.