Every kyudo bowstring has a loop at each end. The loops are called tsuruwa (弦輪, “string ring”), and the one you will be asked to tie yourself sooner or later is the loop that sits on the urahazu (末弭), the upper tip of the bow.
Beginners usually find the tsuruwa the hardest part of setting up a new string. The Suizan kyudo shop puts it plainly: tying the tsuruwa is difficult and slow at first, so it is worth learning early (Suizan, “Choosing a bowstring”, in Japanese, checked 22 October 2026).
This page does not try to replace your teacher’s hands. It covers what the Japanese federation and the Nippon Budokan actually say about the loop — and those few points explain most of the mistakes people make.
In short
- There are two kinds of tsuruwa knot: single (hitoe-musubi) and double (futae-musubi).
- Too small for the urahazu, and the string breaks easily. Too large, and it is unstable and bad for the bow.
- Re-tying the loop again and again makes the string break more easily. Get it right in as few attempts as you can.
- Where you tie the loop decides the working length of the string, and so the gap between grip and string (kyuha).
- Learn the knot from a teacher or senior at your dojo, with the string in your hands.
What the tsuruwa does
The tsuruwa is the loop that holds the string on the bow tip — the urahazu at the top and the motohazu (本弭) at the bottom. The order of putting the string on is explained in How to String a Yumi.
Its size and its knot are what the federation’s guidance is about.
Single knot or double knot
The All Nippon Kyudo Federation’s beginner page on equipment says: “There are two kinds of tsuruwa: the single knot and the double knot” (All Nippon Kyudo Federation, “Equipment”, in Japanese, checked 22 October 2026).
The Nippon Budokan’s instructor’s text for kyudo notes that there are single, double and other knots, and its drawing shows the double knot (Nippon Budokan, kyudo instructor’s text, chapter VII, p.108, PDF in Japanese, checked 22 October 2026). Which one your dojo uses is a matter of local teaching, so follow the knot your teacher shows you rather than mixing methods from different sources.
The right size: fitted to the urahazu
Both the federation and the Budokan text give the same rule, measured against the bow tip itself:
| Loop size | What happens |
|---|---|
| Too small for the urahazu | The string breaks easily |
| Too large | It sits unstably, which is bad for the bow |
There is no single number in millimetres here, because tips differ from bow to bow. The reference is your own bow’s urahazu. Tie the loop on the bow you will shoot, not on a different one.
Why you should not keep re-tying it
The federation adds a warning that surprises many beginners: re-tying the tsuruwa repeatedly makes the string more likely to break.
So the aim is to reach the right position in as few attempts as possible — which is why learning the knot properly, once, under supervision, saves strings.
The loop sets the string’s length — and kyuha
The position of the loop decides how long the string is between the two tips. That length in turn decides the kyuha (弓把) — the distance between the grip and the string.
- Strings come in lengths to match the bow: the federation notes that “bowstrings, like bows, come long and short”. Suizan adds that a string made for a standard-length (namisun) bow does not fit a longer bow such as a nisun-nobi — check your bow’s length before buying strings.
- New synthetic strings stretch. Suizan recommends tying the loop a little short of the correct length at first.
- Suizan also suggests stringing the bow with the kyuha on the high side and drawing it several times without an arrow (subiki) before you make the nakajikake (the wrapped nocking point). Letting the string settle first means fewer re-ties — which, as above, is exactly what you want.
If you are unsure how high the string should sit on your bow, ask your teacher to look at it strung. Kyuha depends on the bow, and the same number is not right for everyone.
When you actually tie one
You will meet the tsuruwa in three situations:
- Preparing a new string before you need it. The federation advises always preparing a spare string, shooting it in for a few arrows, and keeping it ready on the string reel (tsurumaki). How to keep a spare that is genuinely ready is covered in Spare Kyudo Bowstrings and the Tsurumaki.
- Replacing a worn string. When to retire a synthetic string is in Kyudo Bowstrings: When to Replace Them.
- Correcting the length of a string that has stretched. Do this sparingly, for the reason above.
Frequently asked questions
Can I learn the knot from a drawing or video alone? The Budokan drawing is a good reference, but the loop has to fit your own bow tip. Have someone experienced check your first loops on your bow.
Which knot should I use, single or double? Both are described by the federation. Use the one taught at your dojo.
My loop slipped and the string now sits too low. Should I just re-tie it? You may need to, but each re-tie shortens the string’s life. Ask a teacher to check the cause first — a loop that is too large for the urahazu, or a new synthetic string that is still stretching, need different fixes.
Is the lower loop also something I tie? The loop you will be asked to tie is the one for the urahazu. When buying strings, ask the kyudo shop how the string is supplied and which end you need to finish yourself.
Summary
- The tsuruwa is the loop that holds the string on the bow tip.
- Two knots exist — single and double. Follow your dojo’s method.
- Too small for the urahazu breaks strings; too large is unstable.
- Re-tying repeatedly weakens the string. Aim to get it right in few attempts.
- The loop sets string length and kyuha. New synthetic strings stretch: tie a little short and do subiki before making the nakajikake.
Sources (all checked 22 October 2026, in Japanese): All Nippon Kyudo Federation, “Equipment” / Nippon Budokan, kyudo instructor’s text, chapter VII / Suizan, “Choosing a bowstring”. For your own bow, your teacher’s guidance comes first.