String Pops off Cam - Why?

nethunter · 10-25-2007, 12:22 AM

Have been shooting a Hoyt split limb and just had the string pop off the cam. Can anyone please tell me why/how this could happen, and how to prevent it? It's a two cam bow with standard Y cables to the axles.
Thanks in advance.

shott8283 · 10-25-2007, 04:13 AM

extreme cam lean.. is my only guess.. i am no expert but thats one thing that pops out in my mind.

BGfisher · 10-25-2007, 06:14 AM

When is it popping off the string? Torque induced by the shooter can cause this. Twist the string and/or torgue the bow and it's likely to happen. Especially when trying to let down.

Also if you have, say, a 70# bow and it's backed off to 60# then there may not be enough tension on the rigging, which can cuse it.

Cam lean is another possibility.

Then again, it could be a combination of any or all of these.

nethunter · 10-25-2007, 09:25 AM

BG and Shot, thanks for the tips.

The cams do appear to be leaning, even when they are not under tension.

They lean more when drawn. It is at rated poundage for the limbs.

Since I don't typically 'hold' the handle, and use a D-Loop, there must be some other explanation for the cam lean besides torque.

Quote:

Especially when trying to let down.

Yep, just when starting to let down.

Any ideas as to why the cams lean, and possible corrective actions would be appreciated.

Arthur P · 10-25-2007, 09:39 AM

Several things can cause cam lean. The cable harness might need adjustment. Cam bearings might be worn out and need replacing. The axles might be bent and need replacing. One of the limbs might be going bad. I'd get that bow to a Hoyt dealer post haste and have it thoroughly checked over before shooting it again.

KodiakArcher · 10-25-2007, 10:49 AM

If you're not a techie then follow Art's advice and get it into a shop. It may just be as simple as taking some creep out of the strings and cables and then locking down that damn Hoyt floating harness so the limb tips/cam lean can be brought back in tune, or something more sinsister may be afoot.

mobow · 10-25-2007, 11:06 AM

The cam might actually be collapsing as well. We had a Trykon XL that had your exact problem. Hoyt told us that they made.......ahhhhh, I can't remember how many, but it wasn't too many, that the cam wasn't strong enough in longer DL's, like 31 and 32 inches. That was this one's problem, the cam was collapsing and the string would jump off about every 2 or 3 shots.

nethunter · 10-25-2007, 11:07 AM

Some good ideas.

Tried swapping one Y harness ends on the axles - no difference - that should have made it lean the other way, no?

Took off one of the cams - they both lean.

Rolled the axle and it appears straight. Could put an indicator on it, but with this amount of lean, it should be noticeable.

No slop in the cam bearing. Some minor slop in the four limb holes.

KodiakArcher · 10-25-2007, 11:39 AM

Quote:

ORIGINAL: nethunter

Some good ideas.

Tried swapping one Y harness ends on the axles - no difference - that should have made it lean the other way, no?

Took off one of the cams - they both lean.

Rolled the axle and it appears straight. Could put an indicator on it, but with this amount of lean, it should be noticeable.

No slop in the cam bearing. Some minor slop in the four limb holes.

Does it have floating "Y" yokes or static yokes? If they float then changing them end for end isn't going to help any.

nethunter · 10-25-2007, 12:26 PM

Quote:

and the string would jump off about every 2 or 3 shots.

Ouch! The cams don't appear to flatten, BTW, and they didn't do this for hundreds of shots in the past.

Quote:

Does it have floating "Y" yokes or static yokes? If they float then changing them end for end isn't going to help any.

These are 'upgrades' - cables run straight thru the Y to the ends, as opposed to having a sliding thingy at the Y. Would that be static?

Just pulled the other cam. Axle is straight, no significant slop in the cam sleeve, but again some slop in the limb holes.

To derail the thread here, found a webcam with the ranch I built in view. The fire swept thru there twice, and there is a huge mushroom cloud in view. Everything is burned all around the ranches at the bottom of the canyon, but they appear to be untouched. God Bless those volunteer firemen and others who came to help!