Drive belt tension!
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Joined: Oct 2009
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From: Here
This might help
DEFLECTION
DEFLECTION
PART NUMBER TOOL NAME
HD-35381A BELT TENSION GAUGE
NOTE
Always use BELT TENSION GAUGE (Part No. HD-35381A)
to measure belt deflection. Do not rely on "feel" as this can
result in belts that are under tensioned. Loose belts will fail due
to "ratcheting" (jumping a tooth).
Always use BELT TENSION GAUGE (Part No. HD-35381A)
to measure belt deflection. Do not rely on "feel" as this can
result in belts that are under tensioned. Loose belts will fail due
to "ratcheting" (jumping a tooth).
Check deflection:
As part of pre-ride inspection.
At every scheduled service interval.
With transmission in neutral.
At loosest spot in belt.
With motorcycle at room temperature.
With motorcycle upright and rear wheel off the ground or
on jiffy stand without rider or luggage.
1. Remove left side saddlebag.
2. Slide O-ring on gauge toward 0 lbs (0 kg) mark.
3. See Figure 1-18. Fit cradle against bottom of belt midway
between transmission sprocket and rear sprocket.
4. Push upward on **** until O-ring slides to the 10 lbs (4.5
kg) mark on the tool and compare belt deflection to scale
on debris deflector.
on jiffy stand without rider or luggage.
1. Remove left side saddlebag.
2. Slide O-ring on gauge toward 0 lbs (0 kg) mark.
3. See Figure 1-18. Fit cradle against bottom of belt midway
between transmission sprocket and rear sprocket.
4. Push upward on **** until O-ring slides to the 10 lbs (4.5
kg) mark on the tool and compare belt deflection to scale
on debris deflector.
NOTE
Each graduation on the scale represents 1/8 in (3.2 mm) of
belt deflection.
Each graduation on the scale represents 1/8 in (3.2 mm) of
belt deflection.
5. Measure deflection at several locations around the belt.
Select the loosest measurement and compare with specifications
in
Select the loosest measurement and compare with specifications
in
Table 1-12. Adjust belt as necessary.
Table 1-12. Belt Deflection
MODEL INCHES MILLIMETERS
MODEL INCHES MILLIMETERS
FLHX, FLTRX 1/4-5/16 6.4-7.9
Other models 3/8-7/16 9.5-11.1
Other models 3/8-7/16 9.5-11.1
1
2
3
4
2
3
4
om00156
1. Transmission sprocket
2. Rear wheel sprocket
3. 10 lbs (4.5 kg) of force
4. Amount of deflection
Figure 1-18. Checking Belt Deflection
2. Rear wheel sprocket
3. 10 lbs (4.5 kg) of force
4. Amount of deflection
Figure 1-18. Checking Belt Deflection
SETTING BELT DEFLECTION
PART NUMBER TOOL NAME
HD-35381A BELT TENSION GAUGE
HD-47925 AXLE NUT TORQUE ADAPTER
HD-47925 AXLE NUT TORQUE ADAPTER
Adjustment
1. Remove both saddlebags.
2. Remove and discard E-clip from groove at end of axle.
2. Remove and discard E-clip from groove at end of axle.
NOTE
The AXLE NUT TORQUE ADAPTER simplifies the belt
adjustment procedure by allowing the cone nut to be loosened
and tightened without having to remove the right side muffler.
The tool also can be used to rotate the weld nut on the left
side.
The AXLE NUT TORQUE ADAPTER simplifies the belt
adjustment procedure by allowing the cone nut to be loosened
and tightened without having to remove the right side muffler.
The tool also can be used to rotate the weld nut on the left
side.
3. See
Figure 1-19. Install AXLE NUT TORQUE
ADAPTER (Part No. HD-47925) on 1/2 inch breaker bar,
perpendicular to breaker bar. For best clearance with
muffler, install torque adapter on the outboard side.
ADAPTER (Part No. HD-47925) on 1/2 inch breaker bar,
perpendicular to breaker bar. For best clearance with
muffler, install torque adapter on the outboard side.
NOTE
In order to provide adequate room to install tools on the cone
nut and weld nut, it may be necessary to remove bolts fastening
each muffler to the rear of the saddlebag frame and pulling
each muffler away from the end of the axle.
In order to provide adequate room to install tools on the cone
nut and weld nut, it may be necessary to remove bolts fastening
each muffler to the rear of the saddlebag frame and pulling
each muffler away from the end of the axle.
4. Insert tool up between rear wheel and muffler and onto
cone nut. Loosen cone nut.
cone nut. Loosen cone nut.
NOTE
Since any added length can act as a torque multiplier, the
torque wrench must be perpendicular to the torque adapter.
Since any added length can act as a torque multiplier, the
torque wrench must be perpendicular to the torque adapter.
5. Install AXLE NUT TORQUE ADAPTER (Part No. HD-
47925) on torque wrench, perpendicular to torque wrench.
6. Insert tool up between rear wheel and muffler to capture
cone nut.47925) on torque wrench, perpendicular to torque wrench.
6. Insert tool up between rear wheel and muffler to capture
Tourer
Joined: Jul 2006
Posts: 253
Likes: 16
From:
I have noticed when adjusting the belt to spec then riding the bike after the bike is hot the belt will be tighter than a banjo string. It really tightens up when hot. I adjust a little loose cold then recheck it after the bike is up to temperature. If the belt is too tight it is hard on transmission seal and bearings.
Outstanding HDF Member
Joined: Oct 2007
Posts: 3,437
Likes: 15
I have noticed when adjusting the belt to spec then riding the bike after the bike is hot the belt will be tighter than a banjo string. It really tightens up when hot. I adjust a little loose cold then recheck it after the bike is up to temperature. If the belt is too tight it is hard on transmission seal and bearings.
I put about 80,000 miles on mine since that time and the belt and both front and rear pullies show no wear. Have not had a seal or bearing issue either.
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Road Master
Joined: Feb 2005
Posts: 1,109
Likes: 3
From: Chattanooga, TN
When adjusted correctly using the gauge to the correct spec it will feel very tight. Sometimes it takes a few tries of tightening and checking and re-checking to get it right. Don't go by the hand feel method, use the gauge!
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Club Member
Joined: Jun 2009
Posts: 5,323
Likes: 37
From: NJ
I talked to a Harley factory engineer about this when the narrower belts came out in 2004 and he said that if the belt was adjusted properly when cold which when you are supposed to adjust it that it will in fact in his words be tight as a drum. he said that is how they are designed and that one of the toughest things was getting shop techs to tighten the belts properly as most end up being too loose. He said if you think it is too tight it is probably just right.
I put about 80,000 miles on mine since that time and the belt and both front and rear pullies show no wear. Have not had a seal or bearing issue either.
I put about 80,000 miles on mine since that time and the belt and both front and rear pullies show no wear. Have not had a seal or bearing issue either.
Same here...Purchasing dealer gave me the bike with the belt FLOPPING.....I left him and went to another dealer and the belt is indeed banjo tight....no problems...been tight like this for 8 K...
Extreme HDF Member
Joined: Sep 2005
Posts: 11,615
Likes: 50
From: Baton Rouge, LA
I have noticed when adjusting the belt to spec then riding the bike after the bike is hot the belt will be tighter than a banjo string. It really tightens up when hot. I adjust a little loose cold then recheck it after the bike is up to temperature. If the belt is too tight it is hard on transmission seal and bearings.
I wouldn't go tighter than 7/16" cold on an SG with stock 12" shocks or 1/2" on those with 13" shocks, and would want no less than 1/4" of deflection once hot in any case. I'm referring to the 10# standard discussed above for measuring the belt tension.