Which of the strings listed below should be pre-stretched and at what percentage? ASHAWAY Zymax 70 ASHAWAY Zymax 67 ASHAWAY ZyMax 65 ASHAWAY Zymax 62 ASHAWAY Micro Legend XL ASHAWAY Flex 21 ASHAWAY Rally 21 VICTOR NS-880Z TI VICTOR VS-850 VICTOR VS-800 VICTOR VS-760 VICTOR VS-660 VICTOR VS-650 YONEX BG55 YONEX BG65 YONEX BG65Ti YONEX BG68Ti YONEX BG70 YONEX BG66 YONEX BG66UM YONEX BG80 YONEX BG80POWER YONEX NG95 YONEX NG98 YONEX NG99 Feel Free to extend the list
I will be honest with you I have had rackets strung and strung rackets with a pre stretch of 10% and also rackets without any machine pre-stretch on. I find rackets strung without a Machine pre stretch to be more lively for their tension and I observed no increase in frequency drop(string tension) with no pre stretch, so I don't do it/get it for those reasons. Strings only last me 2/3 weeks at very most, so not observed beyond this with tension loss. I use bg65 mostly. I always pre-stretch by hand to remove coil though.
Which of the strings listed below should be pre-stretched and at what percentage? ASHAWAY Zymax 70 ASHAWAY Zymax 67 ASHAWAY ZyMax 65 ASHAWAY Zymax 62 ASHAWAY Micro Legend XL ASHAWAY Flex 21 ASHAWAY Rally 21 VICTOR NS-880Z TI VICTOR VS-850 VICTOR VS-800 VICTOR VS-760 VICTOR VS-660 VICTOR VS-650 YONEX BG55 YONEX BG65 YONEX BG65Ti YONEX BG68Ti YONEX BG70 YONEX BG66 YONEX BG66UM YONEX BG80 YONEX BG80POWER YONEX NG95 YONEX NG98 YONEX NG99 Feel Free to extend the list
I think it was Mark A that had a graph showing that pre-stretching reduced the rate of tension loss, but eventually it would reach the same settled tension as a non-pre-stretched string. So for example a prestretched string at 25 lbs. might settle in 3 weeks when it might take the same string but not pre-stretched 1 week to settle. The only way to have a higher settled tension is to string at a higher tension. So you could do 1 lb. higher for example. So prestretching, doesn't prevent tension loss, it just reduces the rate of loss. Technically then, all strings can be pre-stretched. But the string's properties would affect its rate of tension loss. Bold = to my knowledge doesn't need prestretching. Underline = to my knowledge, does need prestretching Italics = not sure ASHAWAY Zymax 70 ASHAWAY Zymax 67 ASHAWAY ZyMax 65 ASHAWAY Zymax 62 ASHAWAY Micro Legend XL ASHAWAY Flex 21 ASHAWAY Rally 21 VICTOR NS-880Z TI VICTOR VS-850 VICTOR VS-800 VICTOR VS-760 VICTOR VS-660 VICTOR VS-650 YONEX BG55 YONEX BG65 YONEX BG65Ti YONEX BG68Ti YONEX BG70 YONEX BG66 YONEX BG66UM YONEX BG80 YONEX BG80POWER YONEX NG95 YONEX NG98 YONEX NG99
Zymax strings and Yonex BG70 don't need prestretching. BG80, 85, and NBG 95, 98 are ok without prestretching. I agree with phaam's recommendations except BG65Ti. I found it loses tension rather quickly without prestretching. Sorry for being a spelling Nazi but did you mean Victor NS660Ti?
i feel BG65Ti and BG66UM should be pre-stretchered. There two strings string lose tension very quick. If pre-strech slows down the process of losing tension, then i think strings should be pre-stretchered
That's what I am saying, personally I have not found that it slows the process down(tested using frequency), used 66um as well. Find middle of string, put it round a door knob, pull at the two ends together. No need to worry about a specific pressure because: Too little = just means their might be coil left in the string(bit of a pain for stringing, that's all) Too much = not possible by hand. The string will slip through your hand before you get to even 15lbs and you will string at higher than that anyway so the string will know no difference(If you can pull harder than that your door knob will probably rip off the door as a safety stop)
If I hand prestretch like that, my hands would bleed and the door knob would definitely come off. I just loop it around a stair spindle and curl up a short length of the ends around a wooden spatula handle (any handle smooth and round would work), and then yank with steadily increasing tension until I see that there's not much slack left. But don't overdo it or else you'll have a string that won't feel lively.
I prestretch everything - no reason not to, and it's become automatic for me now. It's a good way to get the string to behave itself, too, especially coming from a pack.
I find strings like BG 66UM & BG 65ti move abit on the mains whilse playing, where as BG 80 string main retains the alignment. Can pre-streching help to avoid the mains string moving whilse playing?
66 and 65Ti move more because they're more slippery; BG80 is very rough. Prestretching won't keep things in line - you've just got to wait until the strings "bite" into each other.
Thanks Mark for sharing this information. I had a general question relating pre-stretch. I string my voltric 70 at 28 by 29 lbs. Would it be safe to pre-strech at 10% at these tension or above? Well it not damaged or destroy the racket ?