View Full Version : Mpro cam adjustment

03-11-2009, 08:17 PM
Ive seen on here several times that there should be 3/8" to 1/2" of the groove showing on the cam where the string leaves the groove. Mine has way less than that maybe 1/4" how do you go about rotating the cam so there is more groove showing? thanks for any advice in advance.

03-12-2009, 11:14 AM
You have to add twists to the string to shorten it. Or you could take a few twists out of the cable. To do this you can use a press or back out the limb bolts till the string goes slack, but be sure and count the turns you back off the limbs.

The problem with having to small a gap is that when shot the bow doesn't reach brace and stop. The string over travels and in turn the cam rolls closer to the end of the groove. If it gets too short the string can run out of groove and slide off the cam. Sort of like a bicycle chain rolling off a sprocket only a lot quicker and more violent.

03-12-2009, 02:34 PM
Thank you BFisher, about how many twists should I put on it? and when you twist it do you just take off one end of the string and twist it tighter

03-12-2009, 07:18 PM
For starters I would add about 10 twists to the string and see how it looks. Just to balance things I'd add 5 twists from each end. You could stretch the string out and do it all from one end, but it would take it a while to shoot itself in again.

If 10 twists isn't enough the remove some twists from the cable. Maybe two at a time. Put it together and take a look see.

One thing about this you should know. It's going to shorten the draw length by about 1/4 to 3/8". The draw weight is going to drop a little, too. How much I don't know, but shouldn't be more than about 3#.

When you get the cam oriented where it needs to be then measure the brace height and ATA to compare them with factory specs. If they are not close or the draw weight is too low come on back and we'll fix this, too.