If chrome chips or gouges to rear sprocket are large enough to be harmful, they will leave a pattern on the belt face.

1. See Figure 1-39. Inspect each tooth (1) of rear sprocket for:

a. Major tooth damage.

b. Large chrome chips with sharp edges.

c. Gouges caused by hard objects.

d. Excessive loss of chrome plating (see step 2).

2. To check if chrome plating has worn off, drag a scribe or sharp knife point across the bottom of a groove (2) (between two teeth) with medium pressure.

a. If scribe or knife point slides across groove without digging in or leaving a visible mark, chrome plating is still good.

b. If scribe or knife points digs in and leaves a visible mark, it is cutting the bare aluminum. A knife point will not penetrate the chrome plating.

3. Replace rear sprocket if major tooth damage or loss of chrome exists.



Figure 1-39. Rear Sprocket

Rear Belt

See Figure 1-40. Inspect drive belt for:

• Cuts or unusual wear patterns.

• Outside edge bevelling (8). Some bevelling is common, but it indicates that sprockets are misaligned.

• Outside ribbed surface for signs of stone puncture (7). If cracks/damage exists near edge of belt, replace belt immediately. Damage to center of belt will require belt replacement eventually, but when cracks extend to edge of belt, belt failure is imminent.

• Inside (toothed portion) of belt for exposed tensile cords (normally covered by nylon layer and polyethylene layer). This condition will result in belt failure and indicates worn transmission sprocket teeth. Replace belt and transmission sprocket.

• Signs of puncture or cracking at the base of the belt teeth. Replace belt if either condition exists.

• Replace belt if conditions 2, 3, 6 or 7 (on edge of belt) exist.


Condition 1 may develop into 2 or 3 over time. Condition 1 is not grounds for replacing the belt, but it should be watched closely before condition 2 develops which will required belt replacement.

Harley Davidson Drive Belt Teeth

Figure 1-40. Drive Belt Wear Patterns

Table 1-4. Drive Belt Wear Analysis





Internal tooth cracks (hairline)

OK to run, but monitor condition


External tooth cracks

Replace belt


Missing teeth

Replace belt


Chipping (not serious)

OK to run, but monitor condition


Fuzzy edge cord

OK to run, but monitor condition


Hook wear

Replace belt


Stone damage

Replace belt if damage is on the edge


Bevel wear (outboard edge only)

OK to run, but monitor condition

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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