Rotary Linkage on Yamaha 421G

[walldaja]

I have a Yamaha 421G and I just love the sound and response. My only problem is the linkage with the rotor. The linkage runs on the inside of my left thumb (between my thumb and the neckpipe) and I just can't seem to find a good place to keep from hitting my left thumb against it when I play without bending my wrist away from the valve.

Looking for suggestions to help with this. I'm thinking of going to a good tech near me and see if he can move the linkage further toward the bell so there would be nothing between my thumb and the valve. Currently I use a Neotech grip and have tried changing the adjustment of the brace without any major improvement.

Open to suggestions.

Thanks in advance!

[Matt K]

So, the only caveat to this is that Yamaha parts can sometimes be very time consuming to get... but I love the Yamaha linkages on their pro horns. I just had a YBL830 installed on my Shires frankenhorn and love them. It took me like 2 years but I also had a bit of a series of unfortunate events that made it take much longer than it would have otherwise, including covid. It's probably way, way faster.

Since its just a single trigger, you might be able to have a tech switch it from the string linkage to one from say a YSL548. I have that horn too and the linkage looks identical other than the 800 series linkages have an extra little nickel paddle that attaches to the rod.

[Crazy4Tbone86]

Switching from an “under the thumb” lever to an “over the thumb” lever is a rather common modification. I do several of them every year and usually use Bach triggers, which I always keep a few in stock. The Yamahas can be a bit of a hassle to remove because the lever is sometimes brazed on (instead of soft soldered). Still, the modification is very doable.

If you want to replace it with a Yamaha lever, the biggest hassle might be getting the parts. Some Yamaha parts arrive in a few days. Other Yamaha parts might take months. Currently, I am waiting on some Yamaha parts that I ordered two months ago.

[ithinknot]

the biggest hassle might be getting the parts

You could do this with zero new parts - move the saddle further up the bell brace, then just flip the existing lever. You'd need to re-braze the pivot arm/tab onto the opposite side of the main cylindrical lever element, then reverse the direction of the string linkage half of the lever by making a single clean cut and brazing it back together flipped 180 deg.

There's no particular point in this if you've got a suitable new part on the shelf, but it's not much trouble.

[ArbanRubank]

I had the very same problem. When I started using a Neotech trombone grip, that particular problem went away! If you prefer not to have to use it though, perhaps one of the other solutions presented will work for you.

OBTW, I also love my Yamaha 421G. I think it has a terrific sound and is extremely versatile.

[ArbanRubank]

I just remembered that I installed an Etsy trigger guard similar to what is pictured in the link listed below and it largely but not completely mitigated the problem.

https://www.etsy.com/listing/705985100/ ... rs=1&cns=1

When I also subsequently installed the Neotech trombone grip, the situation was then resolved nearly 100 percent.

Best of luck.

[Crazy4Tbone86]

I’m not quite following the logic of “moving the saddle further up the brace and flipping the existing lever.” The YBL-421 saddles are intended to be half on the slide receiver and half on the brace. I don’t know if they can be cut to be only on the brace. If you flip the lever around, the thumb part would be located over rotor cap and the string rod would be projecting forward toward the handslide.

[ithinknot]

I’m not quite following the logic ... If you flip the lever around, the thumb part would be located over rotor cap and the string rod would be projecting forward toward the handslide.

Yes, hence the second sentence - you'd need to re-braze the pivot arm/tab onto the opposite side of the main cylindrical lever element, then reverse the direction of the string linkage half of the lever by making a single clean cut and brazing it back together flipped 180 deg. Here's a terrible drawing.

lever.jpg

Again, unnecessary if there's something else generic and suitable to hand but, if there isn't, not a big deal.

[walldaja]

Thanks for your responses. Soon as I get back in town it's going to my tech.

[hornbuilder]

Yamaha lever bridges are silver soldered on. FYI.

You're also reversing the direction of the valve rotation, which will.make slurring into and out of the valve notes much noisier in the transition.

[Crazy4Tbone86]

Matthew……I have worked on a couple of Yamaha bass trombones in which the lever was brazed on. Might have been a thing they did for only a short time……possibly 1980’s or 1990’s? But they are out there.

Ithinknot……missed the part about flipping the pivot arm. Now it makes sense. Actually, your drawing explained it well!

[Crazy4Tbone86]

You're also reversing the direction of the valve rotation, which will.make slurring into and out of the valve notes much noisier in the transition.

That's an interesting discussion that I have not see on this forum....maybe I just missed it. I believe that the direction that a rotary valves rotates makes a big difference in how a horn plays. I have talked with some players who think that it's all in my head. Back some years, Yamaha intentionally changed the design of some their models so that the rotors would rotate up towards the first port. I'm guessing that their research determined there was a positive difference.

[hornbuilder]

It isn't in your head. It is the difference between the rotor simply re-directing the sound upwards into the valve, or, the rotor cutting off the sound path when the ports are transitioning.

[ithinknot]

You're also reversing the direction of the valve rotation, which will.make slurring into and out of the valve notes much noisier in the transition.

That's an interesting discussion that I have not see on this forum....maybe I just missed it. I believe that the direction that a rotary valves rotates makes a big difference in how a horn plays. I have talked with some players who think that it's all in my head. Back some years, Yamaha intentionally changed the design of some their models so that the rotors would rotate up towards the first port. I'm guessing that their research determined there was a positive difference.

Yes! And another reason not to discard string linkages just for the sake of it, without modifying stop arms/bumper plates to retain the correct rotation (I prefer strings anyway, but that's a separate discussion that we needn't revisit).

I've always wondered why some makers chose not to care about this. Kanstul second valves, for example. Or the Duo Gravis, where both are 'wrong' (I'm guessing because it keeps the dual trigger linkage arrangement compact/tidy looking?). Neither direction has some great advantage with water dumping, but there's definitely a difference in the kind of turbulence and resulting sound blips.

Rotary tubas do the same thing, with the traditional arrangement having 1+2 'correct' and 3+4 'wrong'. Keeps the linkages symmetrical, I guess. I've read people argue that it makes no difference because either way you're 'chopping up the sound wave' (colloquially speaking, of course) if not on the opening movement, then on the closing, but this obviously ignores the fact that there is positive air flow/pressure in one particular direction and not the other. (And it pretty obviously doesn't feel or sound the same.) Relatively recently, Miraphone changed all their models to rotate in the same direction, so clearly they agree...

[Crazy4Tbone86]

Exactly! If the rotation is correct, the air is never completely cut off in either direction. No pop....especially if there is some type of venting.

Funny that ithinknot mentions the rotary mechanism arrangement in tubas. When out gigging, I have seen a couple of tuba players who had their rotary valve mechanisms customized to make them all rotate the "proper" direction. The lever arm arrangement looks a little strange because it had to be shifted down on a couple of valves. But if it makes the horns play better.....go for it!

[walldaja]

Got it back from the shop. Really makes the horn work better for me. It's so much better I was able to take the Neotech grip off it and free up either hand for mute swaps.

As some suspected, the original Yamaha pivot was brazed onto the crossbar. Not only that, a slot had been milled into the crossbar and the pivot bracket had a detent that fit into it. My tech filled in the slot and removed the detent. Most of the work was cosmetic restoration.

[Matt K]

That's sweet. The one thing I don't like about the <800 Yamaha series is the linkage. I mean, I like string linkages generally, but I prefer what you have pictured where the bar is on the side & the paddle is wonderful. I typically put woodwind cork on mine. VERY comfortable! FWIW, I was about to say you can also order the 800 series linkages, I've done so myself, but it took FOREVER to get the part from Yamaha. It's totally worth it, I absolutely love the linkages, but I don't think I'd do it again based on how long it took to get the parts. And there were many, many, many parts. More than you'd think for a linkage!

[MTbassbone]

+1 for the Yamaha levers, linkages, and rotors.