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View Full Version : 09 bengal cam-string problem



archer183
03-05-2010, 02:28 PM
I need some help... The string that wraps around the adjustable modules when you draw the bengal, does not wrap into the module, it rides on one side of it and then makes an audible "snap" as it pops in the groove. I took the bow into the shop here, and they can not figure out how to fix it. They moved the spacer washer to the other side, but that did not fix the issue. The bow has never been fired but has been drawn 20-30 times, and is showing wear on the string from snapping into the groove.

any ideas how to fix this? I will try to get a picture up later, if necessary.

thanks
Greg

http://lh4.ggpht.com/_iPCa2wo2FlY/S5GqfC7iUeI/AAAAAAAABdE/5Zb8nl6jh2Q/s800/IMG_0045.JPG

http://lh3.ggpht.com/_iPCa2wo2FlY/S5GqfYRgFpI/AAAAAAAABdI/nJUOYW0cuZE/s800/IMG_0047.JPG

bfisher
03-05-2010, 06:33 PM
I'd like to see a better shot of the cam showing the module where the string isn't in the track. Then show one at rest. Maybe a little farther from the bow and then don't downsize it quite as much.

This could be a case of extreme cam lean, but from the pic it's hard to tell. It just appears that the module isn't seated flush on the side of the cam. Like the module itelf is crooked on the side of the cam. Just can't tell.

archer183
03-05-2010, 06:55 PM
See the pictures below, larger images are at the link
http://picasaweb.google.com/greg.mcfadden/DropBox?feat=directlink

The following images are straight on, undrawn
http://lh4.ggpht.com/_iPCa2wo2FlY/S5HEvkZge4I/AAAAAAAABdY/fgVdtEzGFZQ/s800/IMG_0048.JPG


http://lh6.ggpht.com/_iPCa2wo2FlY/S5HEwDGoYWI/AAAAAAAABdc/jkePWcAosCk/s800/IMG_0049.JPG


The following is side on. The module is fully seated and the channel in the cam and module line up with one another
http://lh6.ggpht.com/_iPCa2wo2FlY/S5HEwgwWORI/AAAAAAAABdk/E7YKPIGEH00/s800/IMG_0052.JPG


The following picture shows the cam drawn. the stop was adjusted by the shop to keep the snapping from happening (and it is causing noticeable wear on the string) while we figure out what is wrong and how to fix it.

If one was to continue the draw another tiny bit, the string would ride up on the rim of the module, and then snap down into the groove.

http://lh5.ggpht.com/_iPCa2wo2FlY/S5HEwX46AuI/AAAAAAAABdg/z0s3ndwyVDo/s800/IMG_0053.JPG

bfisher
03-06-2010, 05:28 AM
Good pics and good explanations. I can see now that the module is fully seated. It lookd wierd in the first pic. Maybe the cable was helping to cause an optical illusion.

OK, here's my assessment. I think your bow has a case of "leaning cam syndrome". Unfortunately, with a single cam there is nothing you can do to adjust the lean out of a cam. Only the idler wheel can be adjusted.

You have a dealer working with you on this. I think he should call Martin customer service and order new parts to correct the issue. Most likely new limbs, but that's not my call. Basically what I'm saying is that if the shop can't fix it then it's definitely a warranty issue.

Montalaar
03-06-2010, 05:35 AM
I agree with Barry. In the last photo it seem as if the string is leaving the cam in the same crazy angle. If possible check the limb for being bent or even the axle. This bow cannot work in this configuration. Maybe you could also measure the length of the cable. Or let the shop do it. A short cable would make your cam lean this bad..

Keep us up to date!

archer183
03-06-2010, 07:11 AM
Will do. question though, are both limbs identical? they certainly appear to be, and if that is the case I can have the dealer swap the limbs around, and put this one on the idler, where it can be adjusted.

bfisher
03-06-2010, 08:17 PM
Yes, the limbs should be the same and can be swapped top to bottom and vice-versa. That doesn't guarantee anything, but it's worth a try.

Before you do that though do something. Measure the A2A on each side of the limbs. See if they are different. Also have the dealer eyeball the cam at full draw to see if is indeed leaning.

archer183
03-06-2010, 09:09 PM
the axle to axle measurement is off by a hair less than 1/16 of an inch.

Spiker
03-07-2010, 07:15 AM
Are the strings routed correctly and cross at the right spot thru the roller guard or cable slide. ??

archer183
03-07-2010, 07:36 AM
Yep, they are routed the same way as shown in the pictures on martin archery's catalog

hunt123
03-07-2010, 09:31 AM
I had a somewhat similar problem on mine in that cam or module was chewing up the serving. The cable wasn't riding correctly. We moved spacers, put on a brand new M2 cam (very smooth, no sharp edges), changed the limb, canted the idler wheel, maybe other things I can't remember and nothing helped.

Went back to Martin several times. Finally on the last return, they managed to somehow get about 1/32" of space between the cable and the edge of the cam when it was drawn. That's awfully close, but nothing's rubbing. Wish I knew what they did so we could duplicate it here if it happens again. I'd say you're going to have to send it back, maybe more than once, until it's fixed. Doubt that there's anything you can do locally.

bowgramp59
03-07-2010, 06:05 PM
it might not help , but looking at the pics. i think the spacers are switched.

archer183
03-07-2010, 06:11 PM
thanks, the folks at the shop tried flipping the spacers, and this is the better alignment...

brushrat
03-07-2010, 06:46 PM
i know you are probably tired of posting pictures ,but something looks quite differant than mine (even though i have an mpro1) . Any chance you could take another picture exactly the same as your last one...except at brace instead of at full draw. Thanks:eek:

archer183
03-07-2010, 06:59 PM
http://lh3.ggpht.com/_iPCa2wo2FlY/S5RqV0azl9I/AAAAAAAABeI/PgCUL2TrT7k/s800/IMG_0054.JPG

I am not quite sure that is the picture you wanted, let me know if it is not.

bfisher
03-07-2010, 07:29 PM
http://lh3.ggpht.com/_iPCa2wo2FlY/S5RqV0azl9I/AAAAAAAABeI/PgCUL2TrT7k/s800/IMG_0054.JPG

I am not quite sure that is the picture you wanted, let me know if it is not.

I think he's wanting one showing the spacers on each side. More of an end view of the limb.

I do want to say you're pretty good with the pictures. With the camera and the computer

archer183
03-07-2010, 07:35 PM
let me take another, these point and shoots have gotten so damn good for the stationary shots, you don't even have to think....

try these three

http://lh3.ggpht.com/_iPCa2wo2FlY/S5RyuDumvYI/AAAAAAAABeU/DWHtwkrXsX4/s800/IMG_0059%5B1%5D.JPG

http://lh4.ggpht.com/_iPCa2wo2FlY/S5RyvEV7KiI/AAAAAAAABec/QP8t4wwHU-Q/s800/IMG_0057%5B1%5D.JPG

http://lh6.ggpht.com/_iPCa2wo2FlY/S5RyvfQ8ZCI/AAAAAAAABeg/wJCm1UZwzJI/s800/IMG_0055%5B1%5D.JPG

brushrat
03-08-2010, 11:09 AM
boy! i agree with everyone else. In some pics it looks like something is preventing the mod from seating flat against the cam. Have you checked the entire cam with a small straight edge to determine if something just didn't get machined true? That cable has way too much angle on it, almost like the cables are connected to the outside of the cable guard instead of the inside??? Have you got "normal" cable to vane clearance ? (i have aprox. 3/16" clearance with my setup, up to 3/8" should be about max)

Spiker
03-08-2010, 11:38 AM
boy! i agree with everyone else. In some pics it looks like something is preventing the mod from seating flat against the cam. Have you checked the entire cam with a small straight edge to determine if something just didn't get machined true? That cable has way too much angle on it, almost like the cables are connected to the outside of the cable guard instead of the inside??? Have you got "normal" cable to vane clearance ? (i have aprox. 3/16" clearance with my setup, up to 3/8" should be about max)

Yeah - it still looks to me like there is a problem with the cable guard/ccs, routing etc...

archer183
03-22-2010, 06:46 PM
no idea what the original problem was, but martin fixed it by replacing the cam with an acu-trak cam.

Also, the module they installed on the cam for changing the draw length is definitely different than the one I had on the original cam. the module is noticeably different in the finish and fit on the rest in my bag - o modules, and by noticeably different, I mean better finish and trimming after molding. In addition, the part lines on the molded module are different.

bfisher
03-22-2010, 06:58 PM
no idea what the original problem was, but martin fixed it by replacing the cam with an acu-trak cam.

Also, the module they installed on the cam for changing the draw length is definitely different than the one I had on the original cam. the module is noticeably different in the finish and fit on the rest in my bag - o modules, and by noticeably different, I mean better finish and trimming after molding. In addition, the part lines on the molded module are different.

OK, so what are you saying? The bow got shipped back to Martin and they updated it with a 2010 cam? Are you happy? That's all that matters. Keep us posted as to how it works out.

archer183
03-22-2010, 07:10 PM
yepo, that is what I am saying. Quite happy about it, no more snapping sound and wear apparent. I have not had a chance to take it out to play yet, but I will say that the changes to the module (damn us engineers, and our incessant curiosity at how stuff is made) are all for the better as far as the surface finish and parting line locations...

cruser
03-23-2010, 08:17 PM
I have an 09 cheetah with the exact same problem and its really becoming a serious problem. I am about to replace this POS string and I do not want this problem to eat my new string. I called martin and the only answer they could give me was to twist the yolk cables to correct the cam lean, but they do not want to hear me when I tell them the cam is not leaning rather the cable enters the module at an extreme angle. I guess my question is, did a martin dealer resolve this issue for you? I bought my bow on ebay and I know of no martin dealer in my area, am I out of luck?

archer183
03-23-2010, 08:29 PM
I dropped it in the mail to martin after the local dealer could not figure out how to fix it. Martin fixed it for me.

-Greg

cruser
03-23-2010, 08:54 PM
Thanks Archer,
I guess I will have to find time to call martin again.