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tmac
12-01-2009, 07:02 PM
I have an 07 bengal and I would like to know how to check cam timing. The string currently comes off the cam exactly where the string groove starts on the cam. Also at rest should the idler be parralell to the string?

JohnnyThunder
12-01-2009, 07:12 PM
You don't need to check the cam timing on a Bengal - it only has one cam, so there is not another cam for it to be either in time with or out of time with. Its possible that someone who knows better will come along and correct me or clarify the answer, but I'm pretty sure that "cam timing" only applies to bows that have a binary cam like CAT duo-cam for instance, and does not apply to bows like the Bengal which has a single cam.

bfisher
12-01-2009, 07:14 PM
Second question first; Yes, the string should track straight off the idler at rest.

Now the cam; You should have the MPro cam and where the string comes off the cam there should be about 3/8" to 1/2" of groove showing. It sounds to me like your cam is way over rotated. A picture would be more definitive though.

There are no timing marks on the cam. Some manufacturers do use them to show the position where the cam performs at it's most efficient, but this is only part of the story. Regardless of where the cam performs best it's sometimes necessary to twist the string or cables to make the bow fit the archer (draw length). If this happens to throw the cam timing off a bit then so be it.

tmac
12-01-2009, 07:29 PM
Yes it is an m-pro cam and I think it is over rotated too.
I can untwist "lengthening the cable" to take care of the over rotation correct? my ata is exactly 32". What ratio do you use on string and cable to keep ata the same while adjusting cam time?

bowgramp59
12-01-2009, 08:49 PM
if you still have the orignal string on your bow, you may want to get a custom string for it. i had a 07 bengal , the string was to long, i couldn't get the peak wt of 60# or the proper ata and brace ht. with that string. a new string fixed all those problems . i didn't have to put any twist at all to achieve all the proper measurments. good luck

bfisher
12-02-2009, 09:35 AM
Yes it is an m-pro cam and I think it is over rotated too.
I can untwist "lengthening the cable" to take care of the over rotation correct? my ata is exactly 32". What ratio do you use on string and cable to keep ata the same while adjusting cam time?

You can untwist the cable and/or add twists to the string. Your A2A sounds OK, but what is the brace height? Bet it's high if the cam is over rotated. Even so by untwisting the cable and twisting the string you can change the cam orientation, but note that this will also shorten the draw length, and reduce the weight range of the bow some.

What I would do is work with both the string and the cable to get the cam properly oriented or at least close. The check the A2A and brace and weigh the bow. If you have to play around with more twisting to get close to specs the ratio between the string and cable should be about 2 to 1.

tmac
12-02-2009, 10:04 AM
What is the correct brace height for this bow 7"?

bfisher
12-02-2009, 03:30 PM
What is the correct brace height for this bow 7"?

Should be right around 7", give or take a hair. A2A should be about
32 1/4", give or take a little.

tmac
12-02-2009, 07:33 PM
I set idler lean and got it pretty straight. The ata is a little short now at 31 7/8-31 15/16. CAM GROVE IS SHOWING APROX 1/4 EXPOSED UNDER STRING . I had to really twist the string a lot and untwist the cable to get cam timing set, may be time for a new set of strings soon. The brace height is dead on 7". I shot it a few times at 20 yards tonight and I did have to readjust the nock height to aprox 1/8 high after all the twisting.Thanks for all the help readjusting.

bfisher
12-03-2009, 08:37 AM
I set idler lean and got it pretty straight. The ata is a little short now at 31 7/8-31 15/16. CAM GROVE IS SHOWING APROX 1/4 EXPOSED UNDER STRING . I had to really twist the string a lot and untwist the cable to get cam timing set, may be time for a new set of strings soon. The brace height is dead on 7". I shot it a few times at 20 yards tonight and I did have to readjust the nock height to aprox 1/8 high after all the twisting.Thanks for all the help readjusting.

Glad you figured out the nocking point deal. I did forget to mention that. Sorry. So how does the bow feel now? Is it a little more quiet?

I'd like to see you post a "clear" picture of just how the string is on the cam. Can you do that?

tmac
12-04-2009, 07:37 PM
here are the pictures of the bengal

bfisher
12-04-2009, 08:39 PM
Sure nuff looks like it's over rotated. Maybe take a few twists out of the cable and add some to the string.. The gap in the picture should be about 3/8" or a tad more. I'd try taking about 5 twists out of the cable and add about 10 twists to the string and see where it's at.

This is going to drop the poundage a bit and shorten the draw length. Don't get too concerned about the draw length. You can always change to the next larger module to gain some length back.

Don't forget that this will change the location of your nocking point (loop) so this should need adjusted again.

Getting the cam rotation better should make the bow more quiet and smooth out any vibration you are feeling.

tmac
12-05-2009, 07:17 PM
Sorry for the wrong manf date it is actually an 08 model. The string orriginally came off the cam at the end of the groove in the cam ,now it's aprox 1/4 inch or more.The max weight is 56 lbs. and it is let out to 30" now. If I untwist the cable any more it wont have any twist left. I guess its time for some new strings.