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Compounded
10-28-2010, 01:10 AM
Hi guys,

My alien x was dry fired about a month ago. I know, tragic...
I just received some new cams and strings in the mail for it and had it all put back together by the fellas down at the archery shop.
I get a phone call at about 2pm saying that the bow is ready to be picked up, BUT, it has some serious issues... My heart sinks... He goes on to explain that there is massive amounts of cam lean on my top limb due to the limb itself being twisted... Pretty crap...
I went in and he took me out back to have a look. He said that when they first set it up and drew it back, one of the cables flicked out of the rail. He had to get another guy working there to get it back in before he could let the bow down.
They then reversed the cables in the cable guard system. This, it seemed, alleviated some of the lean, though not entirely.
He then told me that it may require new limbs, but to go home and try running a few arrows through it whilst wearing safety glasses:cool:
I've done this, the bow didn't explode, but I'm still not sure about it...
I'm a little apprehensive about using the bow with the lean that is still present. So, now I've decided to do some research into how much a set of replacement limbs will be.
After this long narrative, my question is this: Where can I find these prices? The rytera and martin websites don't list limbs. If anyone has a ball park figure it would appreciated.
Any other input too is welcome.

Warm regards! :)

alex
10-28-2010, 02:08 AM
Bfisher can say exactly the price and the item number, but my guess is they'll be around 200$. Are you sure the guys at the shop put together the bow correctly? Are they Martin dealers? And also have you noticed a limb twist before the dry shot?

copterdoc
10-28-2010, 02:35 AM
A dry fire can do a lot of things, but it can't twist the limbs, anymore than it can get you pregnant!

I think the advice you got from your pro-shop was pretty bad. In fact, if you were injured after following it, they would be wide open for a lawsuit!

Your axle could be bent. Your riser could be bent. Maybe they just didn't put the bow together correctly.

If your limbs aren't cracked, or delaminated, and they were straight before the dry fire, then they are still straight now.

alex
10-28-2010, 04:24 AM
Copterdoc, may be if you've dry fired the bow while sitting on the toilet....

bfisher
10-28-2010, 01:02 PM
I don't have a parts catalog for Rytera, but it should use the same limbs as the Martin line. You didn't say what year the bow is, but $200 is a good ballpark figure for new ones. Personally I'd give a call to Joel at Martin Warranty Service and discuss it with him.

My bet is that you'll get new limbs under warranty. He may tell you that you have to return to your dealer and have him handle it, but it's cheaper than $200, right?

Joan@Martin
10-28-2010, 07:27 PM
Guys dry fire damage is not covered under warranty.

However, you could send the bow in to Martin after talking to Vince or Joel and Martin could work on the bow and get it back to good condition.

There is some charges involved with this option... the cost of new limbs if needed, other parts, and the shipping to and from Martin. Give them a call... I am sure something can be worked out.

timtim146
10-28-2010, 08:25 PM
the thing is though if there is cam lean and the riser is not bent then you should be able to work it out by twisting your cables so yeah. maybe they put your strings on wrong and untimed

copterdoc
10-29-2010, 03:40 AM
The Alien-X uses a slaved binary cam system. I don't care if they call it a hybrid cam. It isn't a hybrid cam system!

The cables are both attached to the cams at both ends. There is no adjustable yoke, or any way to laterally adjust the cams. Any cable twisting will only effect cam sync and timing.

I think it is more likely, that the Roto limb pocket is incorrectly installed, or the riser is bent.

Compounded
10-29-2010, 05:10 AM
Is there a difference between the top and bottom limb pockets on these bows? Because that's the only way that they could be installed wrong. To me they look exactly the same.

Compounded
10-29-2010, 05:16 AM
Is there any way to tell if it is the riser that is bent? I've had a close look at it and it does not look at all bent?

copterdoc
10-29-2010, 05:53 AM
The limb pockets are the same, but they have to be seated on the limbs correctly.

The "Roto" part has a machined groove that needs to be seated correctly in the riser as well.

There are ways to tell if your riser is bent, but I can't possibly explain it without showing you in person.

Compounded
10-29-2010, 07:27 AM
With the limb pockets being shaped the way they are, it would be very noticeable if they were not seated properly.
The groove in which the stud of the riser fits is large, as is the stud. If they were not aligned, the bow would not go together, much like a jigsaw puzzle.

I think it may be one of three issues:
1, Bent axle. Although i doubt it.
2, The limb is twisted.
3, The riser is twisted...

If the limb pockets are not in fact symmetrical, it could be that. Though, they do look to be.

I just need to find out which it is... If i had some spare limbs that would make a good eliminatory tool... Sadly, i do not...

Destroyer
10-29-2010, 08:08 PM
but to go home and try running a few arrows through it whilst wearing safety glasses

Stupid advice. Find a new shop.

Doubt very much that the limb is actually twisted. More likely that the limb is poorly aligned, this might be caused by the dry firing or could be the way its been put together too, the shop doesn't sound like they know much at all, giving the idiotic advice they did. Bent axle is easy to check. Wouldn't bother about riser alignment, if its bad the is nothing you can do about it anyway.

Lean can sometimes be fixed by changing the position of the wheel with different axle spacers. Perhaps the new cams are different in some way.

Some pics of the 'bad' lean would be useful. ;)

Compounded
10-30-2010, 12:56 AM
Hi destroyer,

The cams are the very same. The lean isn't only in the cam. As i draw the bow and watch the cam roll over, the limb twists. The twist isn't horrendous, though it is noticeable. As i said earlier the guys at the shop changed the way the the cables run through the guard system to counteract the lean, though it's still present.
When i look down the limb from the front, there is an obliquity to it relative to the limb bolt. It's very slight, only 2 or 3 degrees.
I'm apprehensive about ordering new limbs before I know exactly what the issue is.

Montalaar
10-30-2010, 05:55 AM
Hmm..

You said the lim twists as soon as the cam rolls over. Sounds like you have a wek part in the limb that will tiwst as soon as the force is moved from the string to the cable. This is what happens when the cams rolls into your let off.

Try to remove both limbs (you should be able to do this without problems) and then try to twist both ends of the limb fork. If you can do so with less effort you may have a limb problem. You can also check for a bent axle then!

Compounded
10-30-2010, 07:52 AM
Wow, I wish I knew that already! Sounds very plausible.

Just to clarify:

- As the cams roll over, the string is still taking the load up until just before let off where the force is transferred to the cables?

Would this weak spot be likely to fail? By that I mean should I be very worried about using the bow?

I ran about 40 arrows through it earlier today; the arrow flight was fine, as was the grouping (as fine as i can make it anywho). There was no excess vibration or funny sounds. So, it SEEMS fine, but I don't really think I can afford to lose an eye in this lifetime... ;)

Thank you for your input!

P.S. I have some spare axels I'll throw on it as soon as I can.

alex
10-30-2010, 08:37 AM
The advice to wear eye protection isn't stupid at all. The stupid is that it was given by the people who should take care exactly of problems like this.

Montalaar
10-30-2010, 08:41 AM
As you reported as about your excessive cam lean/limb twist i would not try to put too many arrows through your bow at this time.

Here is a plan:
Remove the tension from your bow. Turn out your limbbolts until you see a tad of light through the whole in the barrel nut. Stop there and try to remove the string from the Cams. this should be no problem as there should be not that lot of tension on the bow any longer.

Now you should have your bow apart. Watch out that the whole thing cannot fall apart when the limbs slip out of the Roto cups so lay it on a soft ground before removing the string and cables. Take a photo before you do so to get it all together after you have done it.

Now remove the axles and check for a bent axle. CHeck also if your cams are straight. With the modern cutouts it can bend a whole cam if a dryfire happens. If anything is straight check for limbtwist. Lay your limb on a flat surface and check if it is twisted. Check if both ends of the limb fork can be twisted against each other. if there is a crack in the limb fork area you will notice it by doing so. I had multiple cracks in that area and they are sometimes hard to see.

Check if your riser is bent. Lay an arrow or anything very straight onto one side of the sight window and check if it is parallel to the rest of the riser. Do this again if you have setup your bow again.

If anything is straight set up your bow again and send it to Martin Archery. No further ideas from me then.

bfisher
10-30-2010, 06:16 PM
As you reported as about your excessive cam lean/limb twist i would not try to put too many arrows through your bow at this time.

Here is a plan:
Remove the tension from your bow. Turn out your limbbolts until you see a tad of light through the whole in the barrel nut. Stop there and try to remove the string from the Cams. this should be no problem as there should be not that lot of tension on the bow any longer.

Now you should have your bow apart. Watch out that the whole thing cannot fall apart when the limbs slip out of the Roto cups so lay it on a soft ground before removing the string and cables. Take a photo before you do so to get it all together after you have done it.

Now remove the axles and check for a bent axle. CHeck also if your cams are straight. With the modern cutouts it can bend a whole cam if a dryfire happens. If anything is straight check for limbtwist. Lay your limb on a flat surface and check if it is twisted. Check if both ends of the limb fork can be twisted against each other. if there is a crack in the limb fork area you will notice it by doing so. I had multiple cracks in that area and they are sometimes hard to see.

Check if your riser is bent. Lay an arrow or anything very straight onto one side of the sight window and check if it is parallel to the rest of the riser. Do this again if you have setup your bow again.

If anything is straight set up your bow again and send it to Martin Archery. No further ideas from me then.

You can try what Simon is saying here if you want to take the time. Personally I'd recommend taking the time just to learn how to do this stuff. And as long as you're playing try swapping thelimbs top to bottom when you put it back together.

Destroyer
10-30-2010, 10:39 PM
As i draw the bow and watch the cam roll over, the limb twists. .

Could be the axle then.


The stupid is that it was given by the people who should take care exactly of problems like this.

Agree. And these ppl are the experts? :rolleyes:

Compounded
10-31-2010, 01:20 AM
You can try what Simon is saying here if you want to take the time. Personally I'd recommend taking the time just to learn how to do this stuff. And as long as you're playing try swapping thelimbs top to bottom when you put it back together.

This is all part of the learning curve. I've been shooting roughly three months now and am not happy with the way I have to learn the pathomechanics of a compound... I'll get there though.

Thanks for all the input. I'll keep you all posted on what the outcome is. (right now i want to mangle the bow "Stupid piece of (muffled words)".

P.S. If you want to not have the problems i have, learn from my mistake: DO NOT let anyone draw your bow without an arrow in it unless you know they can afford to buy you are new one. Sheesh, big mistake! :mad:

Montalaar
10-31-2010, 02:48 AM
This is all part of the learning curve. I've been shooting roughly three months now and am not happy with the way I have to learn the pathomechanics of a compound... I'll get there though.

Thanks for all the input. I'll keep you all posted on what the outcome is. (right now i want to mangle the bow "Stupid piece of (muffled words)".

P.S. If you want to not have the problems i have, learn from my mistake: DO NOT let anyone draw your bow without an arrow in it unless you know they can afford to buy you are new one. Sheesh, big mistake! :mad:

I agree. See also your Martin manual for this kind of advice. Somewhere in this manual are the ten or fifteen rules of 'NEVER DO TO YOUR BOW'. ;)

Destroyer
10-31-2010, 06:16 PM
right now i want to mangle the bow "Stupid piece of (muffled words)".

Lol! It does it to you some time. Eventually you learn not to 'destroy' things. ;)

copterdoc
11-03-2010, 09:12 AM
...The lean isn't only in the cam. As i draw the bow and watch the cam roll over, the limb twists. The twist isn't horrendous, though it is noticeable. As i said earlier the guys at the shop changed the way the the cables run through the guard system to counteract the lean, though it's still present.
When i look down the limb from the front, there is an obliquity to it relative to the limb bolt. It's very slight, only 2 or 3 degrees.
I'm apprehensive about ordering new limbs before I know exactly what the issue is.
What you describe above, is 100% normal for any bow, that uses cams with cable tracks on only one side of the string track. The below quote, is from a post I made on AT, explaining what cam lean is caused by.



....The way you calculate the TOTAL mechanical advantage of the cam, is by measuring the ratio of string/fed-to-cable/reeled.

All cams transmit load through the axles.

The load is always applied on the plane of the cable/string. So, in order to find the starting and stopping points, you need to "draw a line" from the string, to the axle at 90 degrees to the plane of the string.

Mark the location at that point on the string, and draw the bow back with a draw board. Repeat the same measurement at full draw and measure the distance between the two marks. The difference in ATA from brace to full draw, tells you how much cable was reeled in. That will give you the total ratio of mechanical advantage.

That ratio, will be the inverse of the peak draw weight-to-peak limb load. For most modern bows, the cams feed out 3-4 inches of string, for every inch of cable reeled in. That means a 70# bow, has about 245# of total limb load at full draw.

Now, that seems like a lot, but it doesn't even factor in let-off!

We all want let-off right? Well, everything you take from the string, goes right to the cables. If you have 80% let-off, that means that while the string is under 15# of load, the cables are under 230!

At brace, they were all at about the same amount of load. At full draw, the situation changed a bit didn't it?

In order to provide a 30" draw length, a short ATA bow needs to feed out more string, than a long ATA bow does. However, since the total limb compression is limited by the amount of deflection the limbs can withstand, the cams can't be made to reel in 3 extra inches of cable.

That is why short ATA bows, are harder to tune. The popularity of them has increased over the last 10 years, and with it, the cam lean "phenomenon", has been realized.

The only way to solve the problem, is to use cams with an odd number of tracks, or attachment points.

3, or 5 track cams, can maintain lateral balance during the entire draw cycle, including let-off. 2, or 4 track cams, cannot. It is impossible.

When you add the fact that the cable guard itself exacerbates the problem, and adds to the issue by not allowing the cables to pull the limb tips directly at each other, you might possibly realize why these bows are so hard to tune!

There is only one real solution.

You have to shoot the arrow, through the cables.

You have to shoot the arrow, through the cables.

You have to shoot the arrow, through the %$@#$# cables!

Compounded
11-04-2010, 04:13 AM
What you describe above, is 100% normal for any bow, that uses cams with cable tracks on only one side of the string track. The below quote, is from a post I made on AT, explaining what cam lean is caused by.

As I said earlier in this thread, the lean was extreme enough to allow the cable to flick out of the module. That I do not think is normal for any compound bow.

Secondly, the lean was not present before the "issue" arose.

copterdoc
11-04-2010, 05:33 AM
..Secondly, the lean was not present before the "issue" arose.
I don't know about THE lean, but there absolutely WAS lean present before the dry fire!

EVERY SINGLE COMPOUND BOW with an offset cable guard, has cam lean at some point during the draw cycle. If you adjust it out at full draw, the cams will lean at brace. If you adjust it out at brace, they will lean at full draw. This isn't a question of whether these bows have cam lean or not. They ALL have it! It's only a question of how severe it is.

As far as the cable derailment is concerned.....Well that's a different story. Even the bows with the most severe amounts of cam lean, still hang on to their cables!

I think they screwed up the install, more than they are admitting to.

Destroyer
11-04-2010, 06:22 PM
It's only a question of how severe it is.

The only 'lean' we are interested in is severe. Saying all cams have lean is pretty silly, like asking how long is a piece of string? How high is up?

All I do is get them looking square at rest and full draw and the bow usually tunes well.


the lean was not present before the "issue" arose.

Dry firing does bad things to a bow sometimes. ;)


I think they screwed up the install, more than they are admitting to.

Could be right. :)

copterdoc
11-04-2010, 06:49 PM
The only 'lean' we are interested in is severe. Saying all cams have lean is pretty silly, like asking how long is a piece of string? How high is up?
To me, it's only "silly" when somebody finally realizes their bow has cam lean and wants the manufacturer to suddenly fix it.

VERY FEW archers, even realize that their bow's cams lean at full draw. They just shoot the bow.

When something happens that draws their attention to the fact that their cams are leaning and their limbs are twisting, suddenly it's an emergency and they think they have the "only" bow in the world that does this.

The real problem with cam lean, is that the consumer is insisting on it's occurrence. It's not deliberate. They just don't understand what causes it.

They believe that they can have a bow that has the cables pulled 2" over to one side of the limbs and perfectly straight cams, from brace, to full draw.

They demand the impossible. When they start to discover the truth, they complain. They catch a glimpse of the issue, and look for a way to cover it up. They are "demanding" that the bow companies perform magic.

Montalaar
11-05-2010, 01:30 AM
Guys, please come down. :)

Compounded
11-05-2010, 02:40 AM
I don't know about THE lean, but there absolutely WAS lean present before the dry fire!


Not arguing with you on this, mate. Just that the lean in my bow is due to more than the lateral pull the cables exert.

Your spending far too much energy on a moot argument, drop it.

Destroyer
11-05-2010, 07:00 PM
Guys, please come down. :)

What do you mean guys? :confused:

justin
11-06-2010, 06:54 AM
must have ment calm down.


=D i tend to be amazed that bows dont destroy themselves more quickly!!

Montalaar
11-06-2010, 09:53 AM
Yeah, i meant 'calm'. Was a little late this morning...

Destroyer
11-06-2010, 01:21 PM
I wasn't angry? :confused: