Thought experiment; modern Yumi bows

[Sojurn]

With Shogun playing now, it got me thinking about yumi's.  Specifically why they existed in that form and is there a place for a modern bow you hold at the lower 1/3 instead of the middle.
  Is there an advantage to this?
  And can we create an approximation of this with ILF components?

A short bottom limb, with a long (or XL) top limb on a short riser? I presume the limbs would have to be of different wieghts, and a custom string would likely be needed.
  It would be great for hunting on the ground, and it should still manage long draw lengths.
  I'm hoping someone with experience with these bows will chime in, but what does everyone else think?

[McDave]

The shape of the yumi has always fascinated me.  Before replying to your post, I did a quick search on the internet about why the yumi has the shape it does, and how it would compare in performance and accuracy with a modern recurve.  I didn't find anything definitive.  Perhaps you also searched with similar ambiguous results, which is why you posted the question here on TradGang.  I don't believe yumi aficionados have any intention of making the yumi into anything like a modern carbon supercurve, or a full dresser Olympic bow.  So a fair comparison would be a pre-carbon era trad recurve shot off the shelf with no enhancements, the same as many TradGang members shoot, against a yumi at typical trad hunting distances.

My perception is that the yumi wouldn't come off very well.  I have seen videos of yumi shooters with their arms high in the air as they prepare to shoot, which is a movement that would be easy for game to see.  When the question of accuracy is raised on the internet, the response is something like: well, you know, the purpose of shooting a yumi is more spiritual than actually hitting a target.  So,I remain skeptical but would be very interested in seeing a head to head shootoff.

[Sojurn]

Correct on all counts, and insightful as ever Dave.
  Quick and dirty math tells me that a short bottom limb and a XL upper limb on a 15" riser should put the hand in about the right spot, amd make for a 62" bow (I could be wrong).
  And my perception of most Yumi shooters is also that they very concerned with form, and accuracy is a secondary.
  But the bow must exist in that form for a reason, and I can't help but wonder.
  I think its plausible,  but im having a hard time conceptualizing what wieght the two limbs need to be.

[Even]

Its always been my understanding that the Yumi was primarily a samurai weapon, used often on horseback, so the assymetrical limbs made shooting from a horse (during hunting and warfare) much easier.

Think of it as a long horsebow.  The modern use is very different from the historical use, and like Kendo has evolved into a ritual art from its warfare roots, so did the use of the Yumi evolve into its current, ritualized form.

Don't kid yourself though, the heavy bows used in Japanese warfare were just as nasty on the recieving end as middle-age longbows were, and some were contructed quite heavily. 

[Pat B]

Jaap Koppedrayer, at Yumi Bows, could give you information about building Yumi bows and the history behind them.
 I think Even is correct about Yumi bows being used on horseback.  Also, I've heard that the tiller of a Yumi bow is the top limb is tillered as 2 separate limbs, the outer and the inner limb...but Jaap would know better than most of us.