Drive belt tention
Road Master
Joined: Oct 2009
Posts: 1,166
Likes: 14
From: Michigan
How often
I have had several belt drive Harleys and have never had to adjust the tension? Just wonder how many people have? I bought the tool in 1996 and never used it...I'm going to look for it!
Hap
Hap
Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
Consider the belt is semi-rigid in an XY plane, but sufficiently deformable to wrap its teeth into the hollow profile of a sprocket (rotation around the true Y axis).
When you flex (turn) the belt between your fingers you form an arc (bow) between both driving and driven sprockets (fixed points) where the belt teeth are engaged; flexing creates rotation around a 'diffused' X axis, or around a group of longitudinal fibers somewhere along the width of the belt (Y).
If you already had max tension on both types of belt you could only deform them within the limit of their elasticity, i.e. very little perhaps +/- 5 degrees because there is very little difference in length between cord and arc when sag is close to nil; you can only play with the final elasticity of the materials.
When you have normal belt tension the angle of twist achievable between thumb and index can be +/- 45 degrees with the older belts and I get about +/- 10 deg with mine. The stiffness (high modulus) of the new belt also makes it sound at a higher pitch when you make it vibrate.
You have to test this when the bike is cold because thermal expansion of both sprockets makes the newer belt sound like the string of a guitar (on my bike)
When you flex (turn) the belt between your fingers you form an arc (bow) between both driving and driven sprockets (fixed points) where the belt teeth are engaged; flexing creates rotation around a 'diffused' X axis, or around a group of longitudinal fibers somewhere along the width of the belt (Y).
If you already had max tension on both types of belt you could only deform them within the limit of their elasticity, i.e. very little perhaps +/- 5 degrees because there is very little difference in length between cord and arc when sag is close to nil; you can only play with the final elasticity of the materials.
When you have normal belt tension the angle of twist achievable between thumb and index can be +/- 45 degrees with the older belts and I get about +/- 10 deg with mine. The stiffness (high modulus) of the new belt also makes it sound at a higher pitch when you make it vibrate.
You have to test this when the bike is cold because thermal expansion of both sprockets makes the newer belt sound like the string of a guitar (on my bike)
Road Warrior
Joined: Oct 2007
Posts: 1,468
Likes: 4
From: South Carolina
Belt twist method...
Consider the belt is semi-rigid in an XY plane, but sufficiently deformable to wrap its teeth into the hollow profile of a sprocket (rotation around the true Y axis).
When you flex (turn) the belt between your fingers you form an arc (bow) between both driving and driven sprockets (fixed points) where the belt teeth are engaged; flexing creates rotation around a 'diffused' X axis, or around a group of longitudinal fibers somewhere along the width of the belt (Y).
If you already had max tension on both types of belt you could only deform them within the limit of their elasticity, i.e. very little perhaps +/- 5 degrees because there is very little difference in length between cord and arc when sag is close to nil; you can only play with the final elasticity of the materials.
When you have normal belt tension the angle of twist achievable between thumb and index can be +/- 45 degrees with the older belts and I get about +/- 10 deg with mine. The stiffness (high modulus) of the new belt also makes it sound at a higher pitch when you make it vibrate.
You have to test this when the bike is cold because thermal expansion of both sprockets makes the newer belt sound like the string of a guitar (on my bike)
When you flex (turn) the belt between your fingers you form an arc (bow) between both driving and driven sprockets (fixed points) where the belt teeth are engaged; flexing creates rotation around a 'diffused' X axis, or around a group of longitudinal fibers somewhere along the width of the belt (Y).
If you already had max tension on both types of belt you could only deform them within the limit of their elasticity, i.e. very little perhaps +/- 5 degrees because there is very little difference in length between cord and arc when sag is close to nil; you can only play with the final elasticity of the materials.
When you have normal belt tension the angle of twist achievable between thumb and index can be +/- 45 degrees with the older belts and I get about +/- 10 deg with mine. The stiffness (high modulus) of the new belt also makes it sound at a higher pitch when you make it vibrate.
You have to test this when the bike is cold because thermal expansion of both sprockets makes the newer belt sound like the string of a guitar (on my bike)
The only way to check the tension as given in the workshop manual, is to use the belt tension gauge.
I've got to ask, do you ever use a torque wrench on your bike? or do you just do things by guess work all the time.
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Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
All of this depends on how strong you are, now I'm 6'6" 20 stone, compare this to an 8 stone young lady, see where we are going.
The only way to check the tension as given in the workshop manual, is to use the belt tension gauge.
I've got to ask, do you ever use a torque wrench on your bike? or do you just do things by guess work all the time.
The only way to check the tension as given in the workshop manual, is to use the belt tension gauge.
I've got to ask, do you ever use a torque wrench on your bike? or do you just do things by guess work all the time.
Are you familiar with recent belts? I bid and won my spare for 60 quids.
Concerning tools, electrical instruments and literature, I have everything except empty space.
