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Mine has one - I got it used decades ago, but I'm pretty sure that it is stock.

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I do not believe they all had thumbrings. Did they re-design it at some point?

Anyways....some has one of their valve circuits functioning as a hand-rest/grip

It is a fun tuba, sadly discontinued

The leadpipe on the 103 is often the first thing to go bad. ALL of the 103 tubas I have seen had thumb rings. Perhaps the leadpipes on your horns have been replaced and the ring just not put back on.

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My Conn 14J doesn't have a thumb ring, and not having one seems odd. I'm thinking of finding a way to install one, but I've still got bigger fish to fry with that horn right now.

Sorry, I wrote my previous reply without looking. Just checked the horn - no thumb ring. My 621 which is structurally similar does have a ring (I use that horn much more than the 103.)

However, some pictures of 103 show a thumb ring on the lead pipe.

OK. It looks like EVERYONE is correct on the thumb-ring issue. I took a look at the Yamaha parts lists and apparently YBB-103 tubas manufactured prior to 1988 did not have a thumb ring and those made after 1988 did. At least that's what the parts lists indicate.

That's the same time when the split where the old and new style pistons happened. Pre-88 = metal guides. Post-88 = plastic guides. The threads changed on the top and bottom caps at the same time. Pre-88 = fine threads and post-88 = course threads.

The serial numbers pre-88 = under 100,000 and post-88 = over 100,000.

I would expect that the same would apply to the Holton BB662R tubas.

I think I have all the above information straight. If not... I'm sure someone will let me know!

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