Sweet spot difference on ISO vs box frames

Found the following pix on the net which illustrates the sweet spot difference between a traditional box shape and a modern ISO frame - easier to show using the below than trying to explain it.

Another fake racquet from PRC

A friend recently purchased the following fake from PRC via TaoBao after using my Dunlop Biomimetic Evolution. I purchased my pair in 2010.

The below pix shows the fake with yellow strings - looks ok right? Even the skin effect of the Biomimetic series was well cloned.  Upon closer inspection, there are differences.

1. Racquet is 675mm for the FAKE (YELLOW string) vs 670mm of the original and of the specifications printed on the shaft of both the original and the fake.

2. Finger over the wordings on the frame of the FAKE (YELLOW string) feels lumpy (aka printed) vs smooth feel on the original

3. Smear of the BIOMIMETIC on one side of the frame of the racquet on the FAKE (YELLOW string) vs the original

4. Difference of the cap over the handle

5. Grommet layout of the original vs the FAKE (YELLOW string) which is alike an older racquet I bought in 2009.

Fake version in Yellow string

Closeup of bottom grommets on the fake

Fake (YELLOW string) vs original (BLUE string)

Note the difference in the grommets on the 12th position from the shaft. The grommet layout of the fake is as per normal racquets whilst the original has 2 micro-grommets at the same location.

Grommets at top of frame. Fake in YELLOW vs original in BLUE string

Minimal difference here with the fake (YELLOW string) having only a single large grommet. The original has 2.

More grommets on the side of the original

Both the fake (YELLOW string) and the original (BLUE string) have 6 transparent micro-grommets on each side of the frame. However on the original, there is a additional micro-grommet after the last transparent micro-grommet on the top of the frame.

Difference in string layout - overlay of fake (YELLOW string)  over the original (BLUE string)

String pathing differs on the fale (YELLOW string)

Different handle top of the fake (middle)

Pix of grommet layout of friends racquet from same series. He bought his racquet from Malaysia., Grommet structure is as per my racquets in BLUE and WHITE strings.

"Fake" Yonex?

I have came across fake Yonex racquets before but nothing like this. The other fake YY was copy of the ArcSaber FB which was immediately apparent once you pick it up - feels like the original YY Blacken!

This yellow beastie was another animal altogether. Build quality and finishing material quality was superb.

Physical giveaways were the YY logo at the T-joint, as well as the non-aligned wordings along the shaft.

Feels light for a 3U but handles extreme well, like the real thing.

My take is that it is a real Yonex which failed QA or one which was process "wrongly". Reason is because I believe it is a Voltaric I-Force which was finished incorrectly. When I help string the racquet, the grommets layout reminds me of the I-Force, especially the unique position of the last line to be tension on my stringing machine. I would swear it was a I-Force if it was sprayed black and passed to me for stringing!

I enclose the pix(s) below for your review.

String "Notching"

When the strings on a stringbed no longer glides across one another eg stationary, I call the effect "notching".

This is because one of the strings has actually cut into the other to created a "notch" (so to speak) eg partial cut thru. When this occurs, it is a sign your string will need to be replace in the very near future.

"Notching" is extremely common to certain brand and models - Yonex BG66 is probably the most well known of the lot. It even happens if you had the racquet restrung and left it unuse for a while! Someone I know was skeptical and did the above test ... he was disappointed to find the notch after leaving the newly strung racquet unuse for a few weeks!

The effect is most noticable on darker coloured strings - see the enclosed pix from one of my own racquet below. The notches are the white areas on the black string - after I moved the now stationary cross-string aside for the photograph.

Effects of "notching"on the strings

 

Close-up of the "notching(s)"

Even so, Yonex BG66 remains a popular choice for many players ... hence good profits since it has to be replaced often!

Appropriate string tension for the player?

In the recent years, I have receive many stringing request from novice players for tensions above 25lb? 

For instance. One high beginner (aka D-grader in terms of the Commonwealth grading system) was using 27lb. Another, a low intermediate (aka low C-grader or C2-grade) requested for his new racquet to be strung at 28lbs. Yet another - an casual lady player (aka D-grader) was using 30lb??? And so forth. When asked, the startling reason for using such high tensions -  Lee Chong Wei & Lin Dan using 30lbs and above, so a few lbs lower should be right for us???

A coach I know uses this analogy to explain the relationship between stringbed tension and how much strength is require to push the trampoline down to produce repulsion. Think of the racquet stringbed as the trampoline. If you can jump x-meter high on the trampoline (say default=22lb tension), then to reach the same height after the trampoline was set to a higher tension (say new tension=28lb), you need to push down much harder before reaching the previous height again.

Professionals like LCW and LD may require such high tensions as they do weight training and can hit the shuttle at the sweetspot most of the time. The sweetspot is the optimum area of contact between the stringbed and shuttle eg like center of gravity - optimum transfer of energy from stringbed to shuttle. Hence they could push the trampoline down hard repeatedly, with consistency.

Are Yonex strings "Made in Japan" really made in Japan?

Always wondered if the Yonex strings in the plastic packets with  MADE IN JAPAN stamp on them were really made in Japan?

Yonex string packet sold outside Japan

Pricing of the non-JP Yonex strings seem to be quite standard across the globe. However the JP string models made for their local market are always much (MUCH) more expensive eg atleast double the price!

The following are the true MADE IN JAPAN items meant for the local JP market. They always seem to be packaged in box-like containers rather than plastic. 

Various true badminton strings from Japan

If so, does it mean the Japanese consumers are being terribly overcharged for packing in a cardboard box, or, are the oversea(s) customers been sold products not MADE IN JAPAN - vs the stamp found on the packaging?

Searching the internet reveals no additional information regarding locations where Yonex manufacture strings. So much for transparency from Yonex . ..

On the other hand, Ashaway is proud to reveal they only manufacture strings at a single location in the US! Hats off to Ashaway

Alternate stringing pattern

Recently a friend showed me this less common stringing pattern. 

Alternate stringing pattern

In the past the following was use to reduce vertical string movement. The resultant vertical movement is common if a crank-type tensioning device was used because the tensioning mechanism locks when the preset tension has been reach.

Closeup of alternate stringing pattern