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Yes, that is on my list next time it goes in.

Does anyone know…

If the 6450/2165 share the same 5th tuning slide crook? I don’t want to buy the entire 5th slide if I don’t have to…

I’m about to order from MW, the 5th slide assembly for the 6450, as well as outer tubes for the main slide. Dicey, I know, but I had success with the leadpipe and have been getting email responses, so…

Anyone know for sure? I’d assume they are the same, but I am not certain.

I don’t have access to either to measure, but I have seen the 5th valve published spec on the 2165 5th valve as 0.807” (it sits on the small side of the main tuning slide) and the 6450 5th valve as 0.846” (it sits on the large side of the main tuning slide). I would think maybe they’re not the same crook.

MiBrassFS wrote: ↑Wed Jan 22, 2025 4:37 am I don’t have access to either to measure, but I have seen the 5th valve published spec on the 2165 5th valve as 0.807” (it sits on the small side of the main tuning slide) and the 6450 5th valve as 0.846” (it sits on the large side of the main tuning slide). I would think maybe they’re not the same crook.

Interesting, so would the larger bore / sitting in the larger side he f the slide make the 5th valve combos more open then? If so, I'd maybe be tempted to leave it as is for the 2165 to build in a little resistance.

I have no clue on this, just spit balling!

Pauvog1 wrote: ↑Wed Jan 22, 2025 6:52 am

MiBrassFS wrote: ↑Wed Jan 22, 2025 4:37 am I don’t have access to either to measure, but I have seen the 5th valve published spec on the 2165 5th valve as 0.807” (it sits on the small side of the main tuning slide) and the 6450 5th valve as 0.846” (it sits on the large side of the main tuning slide). I would think maybe they’re not the same crook.

Interesting, so would the larger bore / sitting in the larger side of the slide make the 5th valve combos more open then? If so, I'd maybe be tempted to leave it as is for the 2165 to build in a little resistance.

I have no clue on this, just spit balling!

I do think that is the hope in placing it further in the system. The Yorkophones also have the 5th further along after the main slide.

Side note: one of the best responding 5th valves I’ve tried was purposely placed extra close to the 4th (super short ferrule, etc.) to try to make it function more like it was part of the piston valve block. So, in the end, it’s the whole system working together that matters.

Ultimately, I want that main tuning slide to fit plug and play. I don’t think moving the 5th valve will hinder anything, since I like how the Baer plays. I think the smaller main slide and dogleg will give it that extra resistance anyway.

I would imagine that they didn’t use a larger 5th rotor, but they very well could have. If they used the same piston block on each horn, how much sense would a different sized 5th valve make? The Baer’s main slide just doesn’t get to the .846” or whatever it is until the large side; the 2165’s is probably already that big on the SMALL side.

2165 Professional CC Tuba Specifications:
• Bore: 748" - 787", 5th valve .807"
• Bell: 19.69" Heavyweight lacquered yellow brass

6450 Professional CC Tuba Specifications:
• Bore: .748-inch Primary; .787-inch 4th Valve and .846-inch 5th Valve
• Bell: 18.89-inch

This is all I gots… which ain’t much.

There has to be someone(s) here that can do some measuring.

BOO!! If that’s right, looks like I’m into this horn a 5th rotor, too, if that information is correct.

In any case, I asked MW to get me all 5th valve slide tubing. Crook, inner, outer, and those two weird bends out of the rotor.

Keeping in mind, I’m still probably 6 months out from just having all the parts to put on this thing. The wait time is crazy, but at least I don’t pay for them until they’re here.