Does BG66 Ultimax Lose Tension Too Quickly?
Why the Shuttle Feels Different After a Few Sessions
Many players who use Yonex BG66 Ultimax say something like this after a few games:
“The first couple of sessions felt great,
but later the shuttle doesn’t travel as easily.
Does this string lose tension too quickly?”
In reality, most of the time the issue is not excessive tension loss, but a misunderstanding of how this string actually behaves.

The Real Character of BG66 Ultimax
BG66 Ultimax is essentially a 0.65mm high-repulsion string with a medium feel.
Its design characteristics are:
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Thin gauge for quick shuttle release
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High repulsion for easy power generation
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Medium impact feel — not overly soft, but not harsh either
When paired with a suitable tension and allowed to settle naturally, it usually becomes more comfortable to play with after the first few sessions, not worse.
The Most Common Misunderstanding
Many players only remember how the string feels on the first day:
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The sound is very crisp
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The string bed feels extremely tight
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The impact feels sharp and exciting
Then by the second or third session, they notice the string bed feels slightly less tight and conclude:
“The tension dropped too fast.”
But in many cases, the real situation is different.
Typically:
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The racket was strung too tight to begin with (for example 27–28 lbs)
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The string bed has not yet fully stabilized
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After a few sessions, it naturally settles to its true working tension
At the same time, the player’s swing timing and effort may still be adjusted to the “super-tight” feeling of day one. That mismatch creates the impression that the shuttle is suddenly harder to hit.
The Normal Tension Curve of BG66 Ultimax
Understanding the typical lifecycle of the string helps explain the feeling.
Session 1 – Freshly Strung
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Very crisp sound
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String bed feels extremely tight
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Shuttle travels fine but often requires slightly more effort
This is not yet the final playing state.
Session 2–3 – Natural Stabilization
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The string bed relaxes slightly
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Tension settles into its working range
For many players, this is actually when the racket starts to feel easier and more responsive.
Stable Performance Period
Over the next several sessions:
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Repulsion remains strong
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Impact feel becomes more balanced
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Drives, pushes, and quick attacks feel lively
This is typically the best playing phase for BG66 Ultimax.
Near the End of Its Life
As the string approaches breakage:
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The feel becomes slightly softer
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Repulsion decreases gradually
However, as long as the original tension was reasonable, most players can still generate comfortable shuttle speed.

Recommended Tension Approach
One common mistake is jumping straight to very high tension.
For most recreational and club-level players:
24–26 lbs (final playing tension) is usually the most practical range.
Instead of starting extremely high, a better approach is:
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Begin slightly lower (for example 24–25 lbs)
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Play 2–3 sessions
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Observe how the string settles and performs
Then decide whether a small adjustment is needed.
A Practical Tip Many Players Miss
The “super tight and loud” feeling on day one is not the final state of the string.
The best playing window for BG66 Ultimax often appears between:
Session 2 and Session 5
If the racket only feels good immediately after restringing — and quickly feels difficult afterwards — it may simply mean the initial tension was too high for your swing speed.
A well-matched tension should feel comfortable even after the string bed has stabilized.
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