Shuttle speed 76 or 77 for a Dhaka winter court

Shuttle speed is not a grade of quality and it has nothing to do with how hard you hit. It is a mass, printed on the tube, chosen to compensate for the density of the air in the hall. Get it wrong and the court changes size.

The number is a weight

The numbers come from grains, an old weight unit the feather trade never dropped. One grain is 64.8 milligrams. A 77 shuttle weighs about 77 grains. A 76 weighs about 76. The whole argument on this page is 65 milligrams, roughly three grains of rice, sitting in the cork.

75: About 4.86 g. Rare here. Open-air courts in high summer.
76: About 4.92 g. Dhaka indoors, March to October.
77: About 4.99 g. Dhaka indoors, November to February.
78: About 5.05 g. A hall running air conditioning hard in December.
79: About 5.12 g. Not stocked.

Heavier carries further, because a heavier shuttle keeps more of its speed through the same drag. That is why the higher number is called faster, even though nothing about it leaves the string quicker.

Why December and April want different tubes

A shuttle is a drag device. Nearly all of its deceleration comes from the skirt pushing air, so changing the density of the air changes the braking without touching the shuttle. Air at 20 degrees is about four per cent denser than air at 35. A Gulshan hall at seven on a late December morning sits near 18. The same hall in the third week of April sits above 33. That is a full speed step.

Humidity pushes the same way, which surprises people. Water vapour is lighter than the nitrogen and oxygen it displaces, so muggy air is thinner air. June in Dhaka is hot and saturated at once, so 76 is the floor rather than the compromise. Halls also warm during play. A 77 that is honest at seven is flying long by nine, twenty bodies in the room and no air conditioning.

Dhaka sits about four metres above sea level. Nothing on this page is about altitude.

What wrong pace feels like at the back

Too slow

Your clear from the rear corner lands a metre inside the back line however clean the contact. You add arm, the stroke lengthens, the shoulder is sore by the second hour. Lifts die at mid court and get killed. The giveaway is that your net game is unchanged. If only your length has gone, the tube is wrong, not you.

Too fast

Clears sail half a metre past the line. You shorten every stroke to keep the shuttle in, so length becomes something you steer rather than hit. Drives go long. Most players blame their timing and go looking at rackets.

The test, and the one fix

The test is in the laws and takes a minute. From behind the back boundary line, hit a full underarm stroke upward and parallel to the sideline. Correct pace lands between 530 and 990 millimetres short of the far back line. You do not need a tape. The doubles long service line is 760 millimetres inside the back line, the middle of that band. Land on it and the tube is right for that hall on that day. Hit three and ignore the outlier.

A shuttle that is half a step fast can be corrected. Bend the feather tips outward, away from the axis, all sixteen of them. That opens the skirt, adds drag, and slows the shuttle by roughly half a number. It is legal and it is what the back of every club in this city does in April. It is also why we sell 77 in November rather than 78. You can slow a shuttle. You cannot really speed one up.

Why feather dies in a Dhaka summer

Quill is hygroscopic. Too dry and it turns brittle, so the first clean smash snaps two vanes and the shuttle wobbles for the rest of the rally. Too wet and it goes soft, the skirt folds under load and the pace falls away unpredictably. Dhaka delivers both, sometimes in the same week. A tube that spent a May afternoon in a car boot is finished before it is opened.

Tubes live in the cold room at the back, near 15 degrees, capped and upright, out of light. If yours has sat in a kit bag through a dry January, leave it overnight in a sealed box with a damp cloth that is not touching the feathers. Do not soak a shuttle and do not steam one for more than a few seconds. The glue ring at the cork is the first thing to let go. In summer, buy two tubes at a time, not a dozen.

When nylon is the honest answer

For academy sessions, for coaching where a basket of two hundred feeds goes out in an hour, and for social doubles twice a week, nylon is not a compromise. One tube lasts a season where feather lasts an evening.

What you give up is the end of the flight. Feather decelerates hard and drops almost vertically, which is what makes a drop die at the net and a clear stop on the line. Nylon holds its speed longer and falls flatter, so drops sit up and everything plays a little deeper. Slice does much less.

Nylon is graded by cap colour, not by number. Green is slow, blue is medium, red is fast. In Dhaka that means blue from November to February and green from March. We have sold four red tubes in three years.

What a tube should cost

Duck feather, club practice: ৳900 to ৳1,400
Better duck feather, league play: ৳1,500 to ৳2,200
Goose feather, tournament grade: ৳2,800 to ৳4,200
Branded goose, Yonex AS class: ৳4,200 to ৳6,000
Nylon, tube of 6: ৳750 to ৳1,600

Anything sold as goose under ৳1,200 is duck, or it is a refill. Refills are the real problem in this market: played shuttles re-tipped, re-glued and returned to a printed tube. Check the cork for hit marks, check that all sixteen feathers match in length and colour, look for a second bead of glue at the ring. We open one tube from every batch we take in and run the back-line test on three shuttles before the rest goes on the shelf.

Four strong doubles players get through three to five goose shuttles in two hours. At ৳3,500 a tube that is about ৳300 each for the session. The same four on nylon spend that across a quarter.

The short answer

November to February, indoors, no air conditioning: 77.
March to October: 76.
December in a hall running air conditioning hard: 78.
June, still air, sweat on the floor: 76, and bend the tips out if clears still go long.
Coaching, practice, more than three sessions a week: nylon. Blue cap in winter, green from March.

Send a photo of the tube and the speed number from your hall on WhatsApp. We will tell you what you have actually been playing.