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Brian/ ="gjarcher" Posted this great post on restringing a Mathews Monster...excellent info...
http://forums.mathewsinc.com/archery-4/ ... 55#2590055
[quote="gjarcher":2mmmeuds]Time to replace the 2009 OEM string ... a bit overdue, actually. The string and cables look fine, have not crept, but it is 2.5 years and thousands of shots on it. I realize many forum members have reservations about 2-cam bows. First, the AVS is not a true 2-cam bow where each cam is independent and presents timing problems and requires constant checking and retuning. The AVS system slaves the cams, the timing holes make setting each cam as easy as if it were a twin solo-cam bow. So here is how to go about it. Step 1. Organize your accessories and tools, etc., needed to do the job. You don't want to have the bow in the press, unstrung, then have to search the shop for a mis-placed part or tool. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_001_1.jpg[/img] Shown above: Monster bow with OEM string and fall away rest; Allen wrench set including 7/16" wrench; Needle-nose pliers and 5" of thin wire bent in half (or cotter pin) for installing string grubs; Axle removal tool or 3/16" rod (not needed for QC axles); QC Redhead Axles; Spot Hogg Infinity blade rest; 6' tape measure; Notepad & pen; Winners Choice 8190x string set. Step 2. Diagram Cam string and cable routing. Take and record all measurements: RH bow: CAM B on top, CAM A on bottom ATA: 33.5" BH: 6" String Grubbs: 1.5" from cam Present Centershot: 47/64" w/ moleskin (13/16" without). Step 3. Loosen Limb Pocket Locking Bolts and back off limbs 10 turns. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_002_1.jpg[/img] Step 4. Place bow in press. Take care that the press does not contact the AVS or cam before pressing and that the press is adjusted to evenly compress the split limbs. Press the bow just enough to relax the string. Remove the string. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_003_1.jpg[/img] Step 5. Measure from end of loop to bottom of string grub on old string (16.5"). Remove string grubs by pulling off the end loops. Using bent wire (cotter pin) and needle nose pliers, install string grubs on new string and slide into place. Take care to not loose the string manufacturer's number of twists in the string. If string grubs fit loose, they will have to be tied in with nock points to hold in place; do this after the bow is completely setup. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_004_1.jpg[/img] [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_005_1.jpg[/img] Step 6. Install String. Manufacturer inserts a tag to mark the peep location, this end goes on the top cam. Take care to keep the manufacturer's number of twists. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_006_1.jpg[/img] Step 7. Install cables. Undo old cable from cam and undo the connection to the AVS yoke 'washer'. Connect new cable to the washer but do not pull tight and connect the looped end of the cable to the cam. Make sure the loop connection to the washer has twists in it and not left as a loop of individual strands. Repeat for the other cam. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_008_1.jpg[/img] Step 8. Remove an e-clip from on end of the axle. Using Cam Axle removal tool (3/16" chamfered rod), remove cam and lift free (for QC Axle, remove e-clip and pull free). Undo old AVS yoke pigtail from the AVS bearings and slide through the washer and looped cable. Install new AVS yoke pigtail, passing between the looped cable and washer, seating it in the washer groove. Place cam back in position and insert axle, replace e-clip. Repeat for other cam. When installing cables, [b]cable for top cam passes through the inside cable guard roller (silver)[/b] and AVS yoke attaches to bottom cam. Bottom cam cable passes through outside cable guard roller (black) and AVS yoke attaches to top cam. Step 9. Press and unpress bow to get approximate specs. Twist string to get approximate ATA ±¼". Don't worry about BH because it will be too high with bow backed off 10 turns. Adjust cables to get cables in cam timing hole. Remove bow from press and turn limb bolts to maximum DW. Before backing off the bowpress, tension the string by lifting it to seat the string and cables into their respective tracks ... double check that everything is seated and routed correctly ... then back off press slowly, while holding tension on the string. Step 10. Place bow in press and set ATA and cam timing. Use string to get ATA, cam timing should remain fairly close to where it was when bow was backed off. Back off press check tension between cables and string to be about equal. Re-press to fine tune ATA, BH, cam timing and even tensions on cables and string. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_009_1.jpg[/img] Step 11. Put bow in vice and install arrow rest. Set rest so that it is level with string plumb. Adjust rest for launcher to support arrow at berger hole (rest bolt mount hole). (Note: a blade will slightly lift the arrow when at full draw so install slightly below berger hole with blade at about a 30º angle. Nock point should be about ¼-bubble high for a blade rest install). [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_013_1.jpg[/img] Step 12. Check bow performance. Check Max DW; shoot through Chronograph at Max DW. Max DW = 65.7 lbs. This is 2.3# greater than with OEM string and bow in spec and timed. 340.6-gr arrow, bow set at 65.7#/28" (M6 28 80% DL mods), 323 fps. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_010_1.jpg[/img] IBO rating 'up to' 353 fps. Subtract 8.6 fps for DW<70# = 344.4 fps Subtract 20 fps for DL<30" = 324.4 fps Subtract 4 fps Arrow Wt> 5 gr/lb = 320.4 fps Subtract 2 fps for D-Loop = 318.4 fps With WC 8190x string set, bow is shooting about 5 fps over IBO rating. Shoot bow about 25 times, then let set overnight and remeasure all specs. Next morning (today), top cam was slightly under rotated, added 1 twist to cable to bring cable dead center in timing hole. Bottom cam timing, ATA, and BH did not move. Step13. Put bow in final configuration for DW, DL module, and paper tune. Bow set to 60.1 lbs, installed M7 29 65% DL modules. 340.6-gr ACC 3-49, 307 fps. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_014_1.jpg[/img] Paper tune: #1 shot high-right tear. #2 shot, lowered nock point, right tear. #3 Shot, moved centershot toward riser, slight improvement. #4 shot moved centershot more toward riser, no improvement. #5 shot, moved center shot out away from riser beyond initial setting, tear improved. #6 shot moved centershot out more, near bullet hole. [img]http://forums.mathewsinc.com/images/userpix/8674_MonsterReString_015_1.jpg[/img] Final Step. Lock down limb pocket bolts. The bow is now ready to have peep installed, Sight installed and OT2 sight tape made, and walkback, then group tuned, and finally Creep tuned. I am very pleased so far with the WC 8190x string set. Solid, no initial stretch, plus the extra 5 fps I've gained. I hope this has taken some of the mystery out of restringing a Monster/MR-series bow and setting one up. The only tricky part is removing cams to install the AVS yokes, but everything else, the string cable routing, cam timing, etc., is just as easy or easier than a solo-cam, plus no idler lean to worry about and fuss over.
... hope this helps.
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