BMI KARTS chain care and adjustment guide

Chain Care and Adjustments

Chain Care

First, each chain has quite a number 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 pentetrate 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.
The chain tension is adjusted by loosening the motor mounts under your engine and sliding the engine (in either direction) until you reach the proper tension.

Chain Adjustment

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Check the chain adjustment and readjust it if it has more than 1/2 inch flex between the sprockets.
Loosen the engine mounting bolts (under the motor mounting plate) and slide the engine to adjust the chain tension.
Allow between 1/4 inch and 3/8 inch flex for proper adjustment.
Be sure the clutch sprocket and the main drive sprocket are properly aligned.
Tighten the four engine mounting bolts securely after you reach the desired chain tension.
Do not over-tighten the chain or reduced clutch and chain life will result.

How-To Adjustment Chain for Clutch Karts

Remove guards covering the drive components.
Loosen, but do not remove the four engine mounting bolts (1)
3. Slide the engine as nessessary to obtain 1/4" to 3/8" of chain flex.
Be sure the clutch sprocket (2) and the drive wheel sprocket (3) are perfectly aligned.
Securely tighten the four engine bolts.
Recheck chain tension.
Replace the guards covering the drive components. Install new guards if damaged.
Do not over tighten the chain, it will wear down the sprocket teeth in record time.
Best Chain Lubicant

For best chain life, it should be lubricated with a graphite type lubricant such as a spray-on type that evaporates leaving graphite on the chain.
Using motor oil will do but may cause dirt particles to stick to the chain resulting in abrasion. Motor oil is widely used but graphite type lubrication is superior.

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