General
Refer to Maintenance Scheduling → Regular Service Intervals → Regular Service Intervals: 2008 Sportster Models. Primary (front) chain adjustment should be checked at proper intervals and serviced as necessary. If the chain is allowed to run loose, it will cause the motorcycle to jerk when running at low speed, and chain and sprockets will wear excessively. If this happens, see a Harley-Davidson dealer or Service Manual for adjustment procedure.
Table 1. Primary Chain Adjustment: Sportster Models
FREE PLAY
INCHES
MILLIMETERS
COLD engine
3/8-1/2
9.5-12.7
HOT engine
1/4-3/8
6.3-9.5
1Measurement point between sprockets
2Free play measurement
Figure 1. Primary Chain Vertical Free Play: Sportster Models
Procedure
The primary chain can be adjusted without removing the primary cover.
WARNING
To prevent accidental vehicle start-up, which could cause death or serious injury, remove main fuse before proceeding. (00251b)
1. Remove main fuse. See Maintenance and Lubrication → Electrical Protection: Sportster Models.
2. See Maintenance and Lubrication → Transmission Lubrication: Sportster Models → Primary Cover: Sportster Models (XL Model Shown). Remove the two hex socket screws which secure primary chain inspection cover (3).
3. Rotate sprockets to find tightest point on primary chain.
NOTICE
Do not adjust the primary chain tighter than specified. Running chain too tight will result in excessive wear. (00202a)
4. See Figure 2. Loosen locknut (1).
5. Turn chain adjuster screw (2) clockwise (inward) to reduce free play or counterclockwise (outward) to increase free play. Vertical free play must fall within the limits specified. Refer to Table 1.
NOTE
If vertical free play cannot be set within the limits specified, then primary chain and/or chain adjuster are worn beyond adjustment limits. Replace parts as necessary.
6. When tension is set correctly, hold chain adjusting screw and tighten locknut to 27–34 N·m (20–25 ft-lbs).
7. Install primary chain inspection cover. Tighten hex socket screws to 4.5–6.8 N·m (40–60 in-lbs).
8. Install main fuse.
1Locknut
2Chain adjuster screw
3Transmission chaincase drain plug
Figure 2. Primary Chain Adjuster: Sportster Models