Chain check and maintenance

Your Big Twin primary chain should have 3/4" to 7/8" up and down travel when the engine is cold. As the engine heats up, the aluminum expands and the chain should have 5/8" to 3/4" when hot. Take the inspection cover off to check the tension. If you have an adjustable primary chain tensioner, loosen the nut and lift the adjuster to tighten the chain.

Steve

Timing Chain and Gears REMOVAL & INSTALLATION 1.9L Engine NOTE: The following procedure requires the use of the puller tool No. J-25031 or equivalent, and timing sprocket installation tool No. J-26587 or equivalent.

1. Remove the timing (front) cover from the engine.
2. Lock the shoe on the automatic adjuster in fully retracted position by depressing the adjuster lock lever. NOTE: To remove the timing chain, it may be necessary to remove the camshaft sprocket. Before removing the timing chain, be sure to align the timing marks.
   
3. Remove timing chain from crankshaft sprocket.
4. Check the timing sprockets for wear or damage. If crankshaft sprocket must be replaced, remove the sprocket and the pinion gear from crankshaft using the puller tool No. J-25031 or equivalent.
5. Check timing chain for wear or damage; replace as necessary. Measure distance "L'' (40 links) with the chain stretched with a pull of approximately 22 lbs. (98N). Standard "L'' value is 15 in. (381mm); replace chain if "L'' is greater than 15.16 in. (385mm).
6. Remove the automatic chain adjuster-to-engine bolt and the adjuster.
7. To check the operation of the automatic chain adjuster, push the shoe inwards, if it becomes locked, the adjuster is working properly. The adjuster assembly must be replaced if rack teeth are found to be worn excessively.
8. To remove the chain tensioner, remove the "E'' clip and the tensioner. Check the tensioner for wear or damage; if necessary, replace it. Fig. 1: Timing chain guide and tensioner - 1.9L engine
   
   
9. Inspect the tensioner pin for wear or damage. If replacement is necessary, remove the pin from the cylinder block using a pair of locking pliers. Lubricate the NEW pin tensioner with clean engine oil. Start the pin into block, then place the tensioner over the appropriate pin. Position the E-clip onto the pin, then (using a hammer) tap it into the block until clip just clears tensioner. Check the tensioner and adjuster for freedom of rotation on the pins.
10. Inspect the guide for wear or damage and plugged lower oil jet. If replacement or cleaning is necessary, remove the guide bolts, the guide and the oil jet. Install a new guide and upper attaching bolt. Install the lower oil jet and bolt, so that the oil port is pointed toward crankshaft. To install: Fig. 2: Timing chain alignment and installation - 1.9L engine
    Fig. 3: Inspecting the timing chain for wear
    
    
11. Install the timing sprocket and the pinion gear (groove-side toward the front cover). Align the key groove with crankshaft key, then drive it into position using installation tool No. J-26587 or equivalent.
12. Turn the crankshaft so that key is turned toward the cylinder head-side (No. 1 and No. 4 pistons at TDC).
13. Install the timing chain, align the timing chain mark plate with the mark on the crankshaft timing sprocket. The side of the chain with the mark plate is on the front-side and the side of chain with the most links between mark plates is on the chain guide-side. Keep the timing chain engaged with the camshaft timing sprocket until the camshaft timing sprocket is installed on the camshaft.
14. Install the camshaft timing sprocket so that it's marked-side faces forward and it's triangular mark aligns with the chain mark plate.
15. Install the automatic chain adjuster.
16. Release the lock by depressing the shoe on adjuster by hand, and check to make certain the chain is properly tensioned when the lock is released.
17. Install the timing cover assembly.

Depending on how aggressively you ride, chains should be inspected every 500-700 miles, or roughly twice a month

Depending on how aggressively you ride, chains should be inspected every 500-700 miles, or roughly twice a month

Various wrenches. A soft brush, or old toothbrush. An O-ring friendly chain cleaner (if, like most chains, yours is of an o-ring type.) O-ring friendly chain lubricant (again, if applicable.) A new cotter pin (when adjusting the chain tension.) Rags (for wiping grime off the chain.) A rubber mallet (optional.) A rear wheel stand (optional.) A tape measure (optional.

Various wrenches. A soft brush, or old toothbrush. An O-ring friendly chain cleaner (if, like most chains, yours is of an o-ring type.) O-ring friendly chain lubricant (again, if applicable.) A new cotter pin (when adjusting the chain tension.) Rags (for wiping grime off the chain.) A rubber mallet (optional.) A rear wheel stand (optional.) A tape measure (optional.

Various wrenches. A soft brush, or old toothbrush. An O-ring friendly chain cleaner (if, like most chains, yours is of an o-ring type.) O-ring friendly chain lubricant (again, if applicable.) A new cotter pin (when adjusting the chain tension.) Rags (for wiping grime off the chain.) A rubber mallet (optional.) A rear wheel stand (optional.) A tape measure (optional.

Various wrenches. A soft brush, or old toothbrush. An O-ring friendly chain cleaner (if, like most chains, yours is of an o-ring type.) O-ring friendly chain lubricant (again, if applicable.) A new cotter pin (when adjusting the chain tension.) Rags (for wiping grime off the chain.) A rubber mallet (optional.) A rear wheel stand (optional.) A tape measure (optional.

Various wrenches. A soft brush, or old toothbrush. An O-ring friendly chain cleaner (if, like most chains, yours is of an o-ring type.) O-ring friendly chain lubricant (again, if applicable.) A new cotter pin (when adjusting the chain tension.) Rags (for wiping grime off the chain.) A rubber mallet (optional.) A rear wheel stand (optional.) A tape measure (optional.