# hoyt cam and 1/2 timing



## gfm1960 (Jan 30, 2013)

what cables change what and which direction(twist,untwist)to set timing on old style(2005)cam and 1/2 ?


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## nuts&bolts (Mar 25, 2005)

gfm1960 said:


> what cables change what and which direction(twist,untwist)to set timing on old style(2005)cam and 1/2 ?


YOu have a bowstring.
YOU have a buss cable (has three end loops).
YOU have a control cable (has only two end loops).

1) check draw weight...let's say you have a 60 lb draw weight RATED bow
....but, draw weight is only 58 lbs
....you want the draw weight at LEAST 62 lbs...you do NOT like the current maximum draw weight, with limb bolts at maximum

2) TWIST the buss cable shorter, to get the ATA shorter, and the draw weight will go up...stop twisting shorter, when you LIKE the max draw weight

3) sooo, you twisted the buss cable shorter and you NOW get 61 lbs MAX draw weight, with both limb bolts at maximum...you call it GOOD ENOUGH.

4) you are now DONE with the buss cable.

So,
now you focus on the control cable.


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## nuts&bolts (Mar 25, 2005)

HOW do you know if you should ADD a half twist?

HOW do you KNOW if you should remove say ONE full twist?

ANSWER.
TEST it.





STEP 1
20 yards

HORIZONTAL strip of masking tape

FIRE the bareshaft and adjust your sight until you NAIL the top edge of the masking tape.

I ran the TOP edge of the masking tape through the middle of the x-ring.

TUNE the twists of the control cable,
for VERTICAL CONTROL.

We want LEVEL nock travel
which just means,
we want the VANES to take a vacation,
and we want the VANES to do ZERO steering correction.

WHAT does THAT mean????

THAT means,
when we fire the bareshaft
and we miss LOW
and we miss HIGH

you tune the sight, THE SIGHT
to hit the top edge of the masking tape.

NOW,
when you successfully hit the TOP edge of the masking tape,
with the BARESHAFT.,..this is an arrow with NO TAPE at the back end

when you can HIT the top edge of the masking tape...LIKE THIS




We do the NEXT part of the test
and you FIRE a FLETCHED arrow...

NO changes to the sight.

SEE if your FLETCHED arrow misses HIGH or misses LOW.

If your FLETCHED arrow does not kiss the TOP EDGE of the masking tape...

YOU have work to do
on the CONTROL CABLE.



Sooo,
you have a 50/50 chance to GUESS the correct direction
to adjust the control cable (TOP LOOP is easiest to work)

ONLY need to adjust ONE end of the control cable.

Soooo,
you try ADDing 1/2 twist
then,
you try ADDing another 1/2 twist to the top end loop of the control cable
and
then,
you try ADDing another 1/2 twist to the top end loop of the control cable
and
then,
you try ADDing another 1/2 twist to the top end loop of the control cable.

You have now added TWO full twists to the TOP end loop of the control cable.

DID your results get better???

CAn you do THIS??



I aimed at the x-ring with the bareshaft and NAILED the x-ring.
I aimed the fletched arrow WAY WAY LEFT, to avoid killing the bareshaft nock.

This is ONLY a vertical control test.
You want your FLETCHED arrow and the BARESHAFT arrow to have the same height, BOTH touching the TOP of the masking tape.

So,
you kept ADDING more and more half twists to the TOP of the control cable.

EITHER things got BETTER
or they got WORSE.

IF things got WORSE,
then,
remove the 2 FULL TWISTS you added to the TOP end loop of the control cable.

So,
you can guess what is next.

REMOVE 1/2 twist from the TOP end loop of the control cable.
Then,
REMOVE another 1/2-twist from the TOP end loop of the control cable.

REPEAT again and again,
until you get THIS result.


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## nuts&bolts (Mar 25, 2005)

When you get THIS result

at 20 yards...




you are ALMOST (one step closer)
to getting tight groups at 20 yards.


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## gfm1960 (Jan 30, 2013)

the bow doesn't group terrible but when i draw it i can tell there is under rotation in the upper eccentric by the way it fights me a little.my strings were new about 150 shots ago so i'm sure things have settled.just want to get it back to where the draw stop on the bottom eccentric touches the cable approximately a credit card thickness after the top goes into full draw position


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## SonnyThomas (Sep 10, 2006)

Manners of correcting; Always is the cable that feeds into the draw module. Cam too slow, untwist cable that feeds into it's draw module. If too fast, twist cable that feeds into it's draw module. Apply to either top or bottom cam or both as required to maintain reference points...sync/timing so to speak. Then proceed with whatever fine tuning you need. On Hoyt bows many find they like the top cam hitting a tad bit before the bottom cam.


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## gfm1960 (Jan 30, 2013)

SonnyThomas said:


> Manners of correcting; Always is the cable that feeds into the draw module. Cam too slow, untwist cable that feeds into it's draw module. If too fast, twist cable that feeds into it's draw module. Apply to either top or bottom cam or both as required to maintain reference points...sync/timing so to speak. Then proceed with whatever fine tuning you need. On Hoyt bows many find they like the top cam hitting a tad bit before the bottom cam.


thats how it usually gets set up.when the top goes into full draw position,there's a gap about a credit card thickness between the draw stop and the cable in the bottom.makes for a slight bit of valley/pocket to pull into


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## TMan51 (Jan 25, 2004)

SonnyThomas said:


> Manners of correcting; Always is the cable that feeds into the draw module. Cam too slow, untwist cable that feeds into it's draw module. If too fast, twist cable that feeds into it's draw module. Apply to either top or bottom cam or both as required to maintain reference points...sync/timing so to speak.


Sonny Thomas vocabulary check:

Cam too slow = cam not rotated far enough ?

Cam too fast = cam stop hits the cable ahead of the other stop ?



SonnyThomas said:


> On Hoyt bows many find they like the top cam hitting a tad bit before the bottom cam.


This usually cures a chronic nock high when the shaft is square to the string at rest. ?


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## dwagoner (Sep 27, 2007)

gfm1960 said:


> what cables change what and which direction(twist,untwist)to set timing on old style(2005)cam and 1/2 ?


buss cable controls lower cam.... control slaves the top cam to the bottom..... start with buss and some older bows have timing marks to align the cams close, so you can use buss to to that to bottom cam, then control cable to adjust top cam.

if top cam hits before bottom you shorten control, if top cam is away from stops when lower is on stop, then you lengthen control.

this is all if bottom cam is correct from start. 

buss controls DL and DW primarly. String connects the 2 cams so has nothing to do with timing, but does for putting bow into spec obviously....

this is a quick reference of "what does what"


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## Ruttin BUX (Aug 13, 2008)

tag


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## bullseye4 (Jan 28, 2013)

tag


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## YoungHunter33 (Jan 19, 2015)

tagged


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