# Tiller adjustment



## midwayarcherywi (Sep 24, 2006)

Make sure you have a few threads grabbing the bolt. Most risers, if you back out the limb bolts to flush with the riser, that is a good place to stop. As far as tiller is concerned, at this point an even tiller should be sufficient.


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## syme71 (Apr 12, 2013)

That's what I'd like to know - define a "few threads".


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## lksseven (Mar 21, 2010)

Sky (the riser manufacturer in Michigan) says keep 6 threads in contact, which I take to mean "from the bolt all the way out of the riser, then 3 revolutions 'in' of the limb bolt"


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## Viper1 (Aug 21, 2003)

syme -

Three full turns is safe.

Viper1 out.


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## Mad Wally (Apr 26, 2013)

Viper1 said:


> syme -
> 
> Three full turns is safe.
> 
> Viper1 out.


Sorry but I disagree. 6 threads in contact can mean nothing else then 6 full rotations in from bolt out!


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## archerynooblol (Nov 6, 2010)

I'd personally appreciate it if the manufacturers would just mark the bolt threads with a red line or some marker, indicating the limit of how far you can turn the bolts out.

Especially for compound bows, where you can't typically see how long the bolt is without pulling the bow apart entirely.


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## Dacer (Jun 10, 2013)

I think larger bolts - the the current hoyt bolt - can be turned out further than the smaller diameter bolts. It's a question I've wondered about. I've turned out my helix bolts to the limit as depicted in the hoyt manual for the helix - and my 32# F7s measure ~ 32.3-32.5# at this setting. Other limbs have measured heavy on my helix too at this bolt setting at my 28" draw


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## ThomVis (Feb 21, 2012)

Engineering wise there are several wisdoms on bolt thread engagement. Some say 3 threads, some say 5 threads, some say bolt's diameter. All dependent on material, stressed involved etc. etc. With this bolt (12mm x 1.25 pitch) 6 threads engaged you should be save.
Original SF Forged+ 25" riser tiller bolts have 14 threads, so with 8 threads showing you should be safe, threads wise. 
But don't assume anything. You're adjusting anyway, so mark the tiller bolt head/shaft, and unscrew while counting turns. This way you can screw it back the same way you have it now. Count the threads while the bolt is out.


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## caspian (Jan 13, 2009)

ThomVis said:


> All dependent on material, stressed involved etc.


plus whether the threads on the bolt are cut or rolled.

stick with the mfr ratings and you won't often go wrong. and if you do, you know who to sue. the latter alone should ensure the former.


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## Vittorio (Jul 17, 2003)

The limit is not in bolt threads, but in dovetail insert angle. I have adjusted several of these risers to the minium possible poundage, and procedure should be the following:

- unstring the bow 
- looking to the side, loose the limbs bolts until you see bolts no more contating the limbs
- in this situation, limbs are kept to the maximum angle (minimum poundage) by the dovetail insert only.
- tighten the limbs bolts at least half tourn more from when they contact the limb again
- adjust tiller, if needed, just loading one of the two bolts a little more.

I use same procedure for all Best risers ...


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## caspian (Jan 13, 2009)

Vittorio, unfortunately thread engagement is where liability lawyers will kick in. I take your point very much about the dovetail angle of engagement, but there is no guarantee that this will be the limiting factor before thread engagement is.


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## K31Scout (Sep 17, 2003)

For Hoyt bows the latest manual says..." From the bottomed out position, the tiller bolt should only	be backed	out to a maximum	of six complete turns."

I looked at the PDF manual for SF Forged and did not see a recommendation.


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## Vittorio (Jul 17, 2003)

caspian said:


> Vittorio, unfortunately thread engagement is where liability lawyers will kick in. I take your point very much about the dovetail angle of engagement, but there is no guarantee that this will be the limiting factor before thread engagement is.


I was referring exactly to the risers mentioned, not to others.


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## caspian (Jan 13, 2009)

K31Scout said:


> I looked at the PDF manual for SF Forged and did not see a recommendation.


the SF "manual" is very poor.

I found this gem on another board in response to an inquiry to SF:

_Hello,
Thank you for your email.
If you unscrewing the tiller bolt completely, you have to make minimum 3 turn of tiller bolt to be safe. A the opposite, the maximum turn is when you can't put the limb on the riser.
If anything is unclear, please feel free to come back to me.
Best regards,
Sebastien Flute._

if you can decode that then you are doing better than I.

personally I'd be bottoming the bolts and going no more than 6 turns out, barring other evidence. have a good look at the thread engagement into the riser, if threads are not showing then you could come out further.


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## syme71 (Apr 12, 2013)

There are 13 threads on the tiller bolt. I ended up having three threads exposed with the bolt just making contact with the limb (about 1/2 turn). I guess this is fine since it leaves ~10 threads in the riser. Next question from what I've been reading is that I should screw in one of the bolts a little more than the other one? if so, top or bottom and how much more than the other?


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## Viper1 (Aug 21, 2003)

syme -

Ah... no.

You set the bolts were you think you want them.
Measure the tiller height from where each limb exits the riser to a point perpendicular on the string, and then adjust the bolts to make the lower measurement approximately 1/8" shorter than the upper measurement. As Vittorio said, it's usually safer to do so by tightening, not loosening one of the bolts.

There can be more to it than that, but that's the default for a new shooter. 

Viper1 out.


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## vaguru (Jan 2, 2003)

I have 4 SF Forged+ risers. I have measured the length of the threads on 2 of them (3/4 inch), and counted the number of turns required to remove the bolts from completely screwed down. In both cases it was 16 full turns of the limb bolt.

Knowing the strength of a threaded bolt does not increase with more threads engaged over bolt diameter, I understand the above posted email from Sebastian Flute. I, however, am personally leery of backing the bolts out more than 8 turns. 8 Turns still leaves 8 threads in the riser (half of the total thread length.).

I have also measured the distance from the top of the riser surface the limb bolt screws into to the bottom of the limb bolt head. I used a dial caliper and for quicker reference a 6" steel scale. Below are my findings, saves changing limb bolt settings to check. 

2 turns out - 25/32"
4 turns out - 28/32" factory setting
6 turns out - 31/32"
8 turns out - 1 1/16" bolt still has 8 threads of engagement in riser
You will notice that there is a 3/32" change for every 2 turns, or 3/64" per turn. 

On the limbs I tested, one turn is aproximately one pound.

I hope this info helps.

BTW, you can download the riser setup info on the SF website, but as mentioned there is no info on limb bolt minimum.



A shipped from factory the limb bolts are 4 turns out, with most recommending no more than 2 turns in either direction.


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## syme71 (Apr 12, 2013)

Thank you all for the info. Very helpful. I ended up 4 turns out to play it safe. My daughter seems to be handling the settings well. As for brace height, I've read anywhere between 8.5-9" is ideal. Right now I have it set at 8 7/8". I'm adjusting brace height by number of twists in string. Is this correct?

The main issue we now is that arrows are starting to group at ~7 o'clock. Her Shibuya sight is bottomed out, full to the left. I can't adjust it any further to bring her point of impact to the right. I have a Shibuya plunger with lightest spring and tension screw backed out pretty far. I adjusted her arrow to "show half way" to the left when looking from behind with strings centered on riser. Arrows are Easton XX75 1416 Platinums. Limbs are SF 14# Axiom+. Any other areas to look at?


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## vaguru (Jan 2, 2003)

If arrows show spine is correct, I would just move center shot to the right to correct for windage. My setup has little to no left of center string to arrow point. If it doesn't work out for you, you can always return the centershot back to where it was, just count turns.


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## ThomVis (Feb 21, 2012)

syme71 said:


> I'm adjusting brace height by number of twists in string. Is this correct?


Correct



syme71 said:


> The main issue we now is that arrows are starting to group at ~7 o'clock.
> [...]
> Any other areas to look at?


What is the tiller setting (3 minus 4 in picture below), nock height and did you try a bareshaft test?


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