# string stretch affect speed?



## souwest_ghillie (Dec 10, 2005)

I had a new string installed on my PSE Thunderbolt last spring and it has stretched considerably since. I've also noticed quite a drop in arrow speed. My setup was never blistering fast but I was shooting around the [email protected], now I'm lucky if I can reach 220fps with the limbs maxed out (maxing out the limbs makes me a little uncomfortable but I did it on the advice of a friend). I also had a new NAP 2000 drop-away installed and have noticed considerable wear marks on my cable guard from the NAP slide (is this normal?). I took my bow to the "pro shop" last August and was told that the string is fine and to just rub some wax on my cable guard (which didn't help). He didn't seem to take my concerns very seriously. My original set-up was a WB and a teflon slide. Could anyone offer some advice as to whether or not some these "issues" are serious and are causing my bow to under-perform? And what changes could I make to improve performance? Should I go back to the WB and teflon slide? I'll post pics of the cable guard later if anyone would like to see the wear marks.


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## bassman409 (Jul 19, 2006)

We have been tuning up a 2000 Thunderbolt with no sticker on the bow and no info available. I went to the pse forum and they recommended that we take the string off and measure it under 100 pounds tension and twist to 96 inchs even and replace it. Same with the 40 inch cable. They said it would shoot fine like that. 
The cable slide is shiny as if you sanded it but works smooth and quietly and there should be no problem with it.
The harness should be set to factory specs and you will get all your speed back and more.


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## souwest_ghillie (Dec 10, 2005)

I registered and checked out the thread as well as others concerning the Thunderbolt. Lots of great info over there! Thanks, bassman!


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## 07 brute (Jan 26, 2007)

*For your cable slide*

I tried wax on the cable slide to, didnt work for me either, I started useing this stuff it works great:wink: http://www.super-lube.com/Merchant2...Code=SL&Product_Code=11520&Category_Code=SHTK

Are you shooting a PSE string cause if you are I would loose that fast, the one on my Brute it has stretched to the point that I gave up trying to keep it in tune,and its still stretching (after about 500 shots)= I got bucknasty string ordered 

One last thing I know that PSE uses a painted aluminum cable guide shaft on their newer bows, when I put the winners choice guide on it I had to buff the paint off the shaft to get it to slide freely.


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## copterdoc (Oct 9, 2005)

String stretch can effect both draw wieght and brace height.

Both of those things will effect arrow speed, but I reeeeaaaaalllllyyyy doubt you would notice the difference unless you shot it through a chronograph.


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## Doc (Jun 10, 2003)

If your cable stretches you are decreasing the draw weight of the bow and increasing the ATA distance throwing the bow out of spec and timing...this will cost you speed. Don't be nervous about maxing down those limb bolts, this is where the bow performs the best. Measure the ATA and BH and I'll bet the ATA has increased and your BH decreased. When the string itself stretches this is going to increase your DL...have you noticed this


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## souwest_ghillie (Dec 10, 2005)

Yes, it's a PSE replacement string. I'm planning on replacing it with a higher quality string. Although I didn't chrono my bow when it was new...I did chrono it last fall. The guys on the PSE forum think that the Thunderbolt should easily reach 270fps with factory specs....maybe more. I really like my NAP drop-away so I'll give that lube a try. As far as DL, I'm not sure....is it possible for the DL to kind of creep up without noticing right away? Like you're unconsciously trying to adjust?


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## phumb (Oct 7, 2006)

is it possible you have the rest cable to tight? at full draw have someone look at your cables, are they pulled closer to the riser? also, i believe string stretch will increase your speed but cable stretch will decrease...


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## powerstroke 1 (Jan 9, 2007)

*String strech*

Yes strech will cause a loss,also your setup must be the same as last chrono (most specificly arrow weight and draw length) to get the same speed.


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## EXTREME 1 (Jan 24, 2004)

The main thing I tell everyone is when your bow is in tune PLEASE record the ATA and Brace and your knock point because when your arrows start to head south you have a refferance to look back on for help. So shen you get that new string and cable set on and the bow is shooting perfectly write down as much info as you can.


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## K-Z0NE (Jan 13, 2007)

Ron Harmon said:


> The main thing I tell everyone is when your bow is in tune PLEASE record the ATA and Brace and your knock point because when your arrows start to head south you have a refferance to look back on for help. So shen you get that new string and cable set on and the bow is shooting perfectly write down as much info as you can.


Something to add to this time saving info: mark the riser at the center of the
berger hole... then draw an arrow and mark at the same point as the mark
on the riser...then measure from the bottem of the nk groove to mark on the
shaft and record the measurement.This will help keep your DL consistant when changing string & cables.

Don't lube the slide as it will attract debris which will make it worse...they are
made to run "dry".


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## mckinstry (Mar 4, 2007)

*string stretch*

YES , string stretch does affect speed ! But if you have the string length of the bow you can put the bow in a press and take pressure off the bow, and
turn the string back to bows string length. Let me know if this works.


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## souwest_ghillie (Dec 10, 2005)

Great advice guys. Since my string is relatively new...I might ask my proshop to twist to the correct length.


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