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OK guys, help a semi-rookie out here.

1. What is cam lean?

2. What causes it?

3. Is it detrimental to arrow flight?

4. Can it be eliminated?

5. Are some bows more prone to it than others?

Thank you!

Sent from my RCT6703W13 using Tapatalk
 

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OK guys, help a semi-rookie out here.

1. What is cam lean?

2. What causes it?

3. Is it detrimental to arrow flight?

4. Can it be eliminated?

5. Are some bows more prone to it than others?

Thank you!

Sent from my RCT6703W13 using Tapatalk
Good question, not knowing anything about wheelie bows, I'd like to know this also.
 
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Best i can explane cam lean is when the half of the cam on the inside of the limb is tilted up and on the outside of the limb is tilted down .
It can be tuned out with yoke cable systems , 2 cable systems , like on the Raven or Tenpoint .
It is most prominent in cable systems where the cables come off the bottom of the cam and anchor underneath the cam on the opposite side , or to the limb via a limb puck , Like the Horton storm , Scorpyd , bowtech ,as examples .

The narrower a ATA gets the more prominent the lean gets . When the bow is cocked the lean gets worse . Reason is you have now anchored the string 14 or whatever inches away from the 2 crossing cables and the angle that they go under the barrel with now narrower ata pulls more at the bottom half of the axles .
Reason is the cables need to be pushed down under the barrel so that you have clearance for your arrow vanes .
So when that happens in the cables systems i mentioned the cables pull more off center and lean the cam .
Cam lean is normal to an extent .


This does not hurt arrow flight at all , BUT it does twist a limb , to much cam lean is the big reason you get cracked limbs , split limb bows can handle cam lean better than solid limb bows .

Hope that helps !!
 

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OK guys, help a semi-rookie out here.

1. What is cam lean?

2. What causes it?

3. Is it detrimental to arrow flight?

4. Can it be eliminated?

5. Are some bows more prone to it than others?

Thank you!

Sent from my RCT6703W13 using Tapatalk

1.block your crossbow level. Put a level on each cam 90 degrees to the rail stock. Both level readings should be the same (level).
2.for cams not to be level, the "Y" end of a cable is out of adjustment due to: one side of the cable "Y" stretching, improper leveling, a bent axle or faulty bearing if the crossbow cams have them, a weak limb or mismatched limb deflection (one limb stronger or weaker than its partner). The Barnett Ghost 410 came with poor quality cam bearings and the bearing axle hole was too large. Replacement bearings came the same so I installed a full one piece bushing with the proper axle hole.

3)if the a cam has enough lean, when the crossbow is shot, the bow string can come off which was the problem with the 2018 Barnett Droptine STR. Correcting this manufacture tuning error, no more problem.

4)Installing high quality cables (built under enough tension and properly served), proper tuning will correct this providing: the limb deflection is the same, no bent axle or faulty cam bearing. Adding 1/2 or full twists to the proper "Y" section of the cable will make the correction. If a cam tilts down, add 1/2 or full twists to the bottom of the "Y" section. If the cam tilts up, add 1/2 or full twists to the upper "Y" section.

5)other members that have had experience with different brands or series of crossbows can probably better answer this. My experience is with the following Barnett crossbows: Barnett Ghost 410, Barnett Buck Commander BCXtreme 365 Ultra Lite, the 2018 Barnett Droptine STR and the Barnett Whitetail Hunter STR Pro.


All the best.
 

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I figure I’ll post my question here as the reply’s might help others.
I have a tenpoint seige rs410 (remember the rs410 if you’re ordering s/c’s)
I’ve installed new s/c’s and have the timing set. When I cock the bow the top cable seems to touch the cam on the outer edge. I haven’t blocked and leveled the xbow n checked level on the cams. I have the same amount of twists on cables top and bottom. Is there normally less twists on top then the bottom? I don’t have a gun vise (yet) so blocking might be a pain. I do have a bog deathgrip I guess I could use. I’m learning as I go. Thank you for the help.
 

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A few things could play a part in what you are seeing:
1)one cable may be a bit longer from manufacture or stretched a bit.
2)where the limbs attach may have been manufactured a shade different
which will show up at the end of the limb.
3)a slight limb deflection (a limb a wee bit weaker than it's partner).

When properly tuned, the cams should be level in the cocked position.

Wishing you all the best.
Take care.
 

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Ok.
It looks like the top cable is more straight inline with the post it connects to and the bottom post is lower then the cam so the lower cable has more of an angle to clear the cam as it rotates.
Is the seige supposed to have equal number of twists in the cable top and bottom?
 

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1.block your crossbow level. Put a level on each cam 90 degrees to the rail stock. Both level readings should be the same (level).
2.for cams not to be level, the "Y" end of a cable is out of adjustment due to: one side of the cable "Y" stretching, improper leveling, a bent axle or faulty bearing if the crossbow cams have them, a weak limb or mismatched limb deflection (one limb stronger or weaker than its partner). The Barnett Ghost 410 came with poor quality cam bearings and the bearing axle hole was too large. Replacement bearings came the same so I installed a full one piece bushing with the proper axle hole.

3)if the a cam has enough lean, when the crossbow is shot, the bow string can come off which was the problem with the 2018 Barnett Droptine STR. Correcting this manufacture tuning error, no more problem.

4)Installing high quality cables (built under enough tension and properly served), proper tuning will correct this providing: the limb deflection is the same, no bent axle or faulty cam bearing. Adding 1/2 or full twists to the proper "Y" section of the cable will make the correction. If a cam tilts down, add 1/2 or full twists to the bottom of the "Y" section. If the cam tilts up, add 1/2 or full twists to the upper "Y" section.

5)other members that have had experience with different brands or series of crossbows can probably better answer this. My experience is with the following Barnett crossbows: Barnett Ghost 410, Barnett Buck Commander BCXtreme 365 Ultra Lite, the 2018 Barnett Droptine STR and the Barnett Whitetail Hunter STR Pro.


All the best.
Amen Bunnyrabbit!

You guided me thru this issue. Thanks again!

I had Ripper 415 cams which weren't aligned causing abnormal nock wear on arrows. The nock was rubbing the right rail hard producing a notch on the nock.
Using the level method you suggested with a long straight edge I determined the right cam lean was slightly out of plane.
Adjustment to the y cable ends by half twist corrected this issue.
Finally check by level showed both cams to be in the same plane and aligned to each other.
Also the undesirable nock wear disappeared. And I should add the right flight rail wear due to this was balanced between both rails which is slight.

Right cam bubble level check:

Automotive lighting Light Automotive tire Bumper Grass


Left cam lean bubble level check:

Automotive lighting Automotive tire Font Personal protective equipment Motor vehicle


Reference bubble level attached to scope ring for reference to set crossbow in fixture to check cam lean shown below.

Watch Tire Photograph Automotive tire Light
 
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