Sunday 17 November 2013

Yamaha EOS + 0.90mm Fishing Line

This racket has a very colourful history. When it was introduced in the 90s, it commanded a price of US$300+. 

Probably the only tennis racket to be made in Singapore till today, it became the basis of contention between Wilson and Yamaha on a copyright infringement.

What Yamaha attempted with this frame was to:
- lower total strung weight to 10oz,
- move most of the weight distribution to the top of the frame to achieve very high SW with as little weight as possible (hence EOS = Efficiency of Swingweight),
- increase stiffness with a thick beam,
- use an open 16x18 stringing pattern for spin, power and comfort.

Sounds like what Wilson did with their Hammer series in the 90s? That's exactly what they fought about. And Wilson won, leading to Yamaha completely bowing out from tennis rackets. 

Despite the settlement, many online posts claimed Yamaha was the first to introduce this design with Wilson following after.

This stick came out from a long "retirement" in the closet. Someone shoved this in my face and asked me if this could still be useful for today's game. I thought, "why not"?

After a short chat about what the owner wanted, and more importantly, completing all the disclaimers (completely waiving me of any potential damage to the racket), I started my unorthodox work.



After measuring and documenting all the specs I could, the first thing is to add weight. Both the owner and myself found this too light. About 50+ grams was added to further polarize the weight. Some was used for stability and dampening.

When pressed, this frame had almost no give. Just like a steel bar. The RA stiffness could be in the 80s, or more, just like their more famous Secret 04 racket.

As with everybody else, the owner asked for more spin. So I strung it up with one of the spinnest setups I knew - a fullbed of 0.90mm fishing line.

Playtest:
- He asked me to play with the racket first and post it in this blog, so I did.
- Despite the stiffness, comfort was impressive. It could be the extra weight I added, but there was absolutely zero harsh vibrations, even framed shots!
- The very extreme weight polarization meant a very heavy dynamic swingweight with excellent maneuverability! Even though total weight was 330g+, it felt very light and fast, but powerful!
- The sweetspot was huge and easy to find.
- High stiffness meant high accuracy too. Aiming was delightful.
- Since this fishing line was proven to generate heaps of spin, what it did no longer surprised me. The usual heaps of ball fur on the string and clinging onto my shorts happened.
- As the strings was more than adept at spin, I flattened out the swing plane to get more depth. The weight placements helped with both spin and power and I adjusted after about 10 minutes.
- After about 45 minutes, a return of serve I hit snapped a mains.
- I think I now know why the owner wanted me to play with it first!





29Nov2013 update:
- After re-balancing this racket, beefing up the grip size, adding dampening, polarizing the weights and numerous strings and tension tests, the owner happily settled for a brand new state-of-the-art Babolat instead!
- He did not even try any of these setups once! 
- In return for the hours of customization work I did, he gave me the racket... What's with people nowadays? 


07Dec2013 update:
- I'm beginning to understand this racket after several hours of use.
- Considering its stiffness, the dampening is absolutely amazing. I can even call this a comfort arm-friendly frame!
- Seems like it was not such a bad deal for me after all...



20Jan2014 update:
- What I like about this racket is that the sweetspot is naturally quite high. So I need not adjust contact points between serves and rallies.
- After many hours of use, a dark patch of string wear appeared on the sweetspot. Good for me to take note so that I can focus on any sweetspot adjustments during my next stringing.







Monday 4 November 2013

Taboo Stringing?

During odd stringing experiments, sometimes the mains snap after the crosses were done. Usually, that meant re-doing the entire stringjob since the crosses were tied to the mains.

After some thought, I decided to modify my racket's grommets to allow tying crosses to crosses. Some modern sticks already have this "feature" in stock form.


I'll let the pictures do the talking...










After the mod was done, I strung the racket to test it out. It worked out pretty well.





However, barely an hour later, the mains snapped!!!



I ran through my mental checklist:

1. Is this a precious racket to me, expensive or hard to find?
2. Am I prepared to risk breakage or warping this frame? 
3. Will I get injured? 

Then I took the plunge... and did some taboo stuff...










Well... the frame remained intact. No cracking nor warping. And weaving the mains was not any more difficult than weaving the crosses. 


I guess this meant another tick for my unorthodox to-do list...


Playtest:

- The racket played a little strange though. The feel of the crosses seemed to appear more dominant than the mains. It could be due to poor mains tensioning from the crosses' frictions? On hindsight, I should have pulled tension twice for each main string.
- There's huge string movement in the mains too.
- It's playable.



05Nov2013 update:
- There must be some string-hungry gremlins running amok... The mains snapped again!!!
- This would be the second time that only the mains were re-done.







Playtest:

- I think this is the second time (link) I tried a fullbed of fishing line and it played very well.
- The feel is much crisper than when hybrid with syn gut. But not as stiff as full poly. Probably crisper than a fullbed of Solinco Tour bite but softer than most polys.
- I would rate this as primarily a spin setup. I could curl the ball anyway and anyhow I wanted.
- Comfort and power were good.
- Despite the very thin (0.9mm) mains line, I was surprised that both flat and spin serves held up so well. Placing the serves were not any more difficult than with my kevlar / syn gut hybrid. So control was very good indeed.
- The sweetspot felt a little smaller than with the syn gut hybrid (link). Or it could be due to the different racket?
- When I examined the strings after about an hour of very hard hits, there was zero notching. Just abrasion marks where the mains and crosses intersect.
- String movement was minimal and there were no huge gaps that caused odd rebound angles.
- When I measured the tension by frequency, the total loss was only about 13% compared to almost 40% when I first tried using fishing line.
- Costs aside, this is a very enjoyable and playable setup for me. Just hope the string gremlins wouldn't chew up this one!




Fancy: 1.20mm Fishing Line / Syn Gut (16x17)

Many thought I was either stingy or crazy to use fishing line. Online reports of those who tried it were mainly negative.

The grade of fishing line I use is very premium. It is made in Japan and available in Japan only. I have not been able to find it anywhere else so far. I'm told it's not nylon. Since I don't understand Japanese, I suspect it could be some flurocarbon-polyethylene hybrid. Maybe with some polyamide added as well.

Among my friends who tried it, about 80% of them loved this string within mere minutes and wanted it done on their rackets. It's only when I told them of the ridiculously high tensions that their jaws dropped and backed off. One chap shamelessly jokingly asked if I could string it on my racket then loan it to him for a month!

Playtest:
- The feel is very similar to the previous hybrid with poly (link). So I know the characteristics of this fishing line in the mains was very dominant.
- This played comfortably, powerful, spinny and very controllable despite skipping two outer cross strings for a 16x17 pattern.
- A friend with recurring tennis elbow pain tried this and liked it immediately too. I think it speaks volumes about the comfort.
- String movement is minimal, maybe just a tad more than with the poly cross. Just look at that ball fur on the strings!




- There was some very light notching on the fishing mains after about 90 minutes of play.