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Well, your first problem is that it's a Yamaha ROTOR tuba!

Otherwise, yes, try oiling everything up really well, including all the linkage, and double check to make sure everything is lined up correctly. Rotary valves are very complex, and the smallest movement can cause a loud, loud racket!

I just got a 641 from the school I will be attending in the fall and it too has fairly clangy valves. I was told by my repairman that I need to add some brass shims because mine had a lot of up and down movement. Have you tried tapping in the caps on the backside of the rotors (sorry I don't know the real name), that was all one of the valves on mine needed but the rest are just bad. Just my thoughts, good luck

Ben

bloke wrote:A competent repair guy can swedge and lap the bearing openings (to remove lateral "play") and machine down the back bearing (to remove vertical "play"). This is affordable...

Hey Bloke,

What is affordable? (Just a guess-timate, please) I ask because I am in a geographically isolated area and it seems at times that the local repairmen are all over the place in price as they operate with little competition. Also I have found a nice used Cerveny 686 that I am interested in, but it seems to me to have very noisy, clanky rotors. Except for that, it is in excellent shape, so I would like to have an idea what my repair cost will be before making an offer on the horn.

Thanks as always for the collective wisdom of TubeNet!

Just thought I would bump this back to the top in hope of finding an answer to my question in the immediatley previous post.

What does this kind of work (lapping and swedging of rotor bearings) run? I am very interested in a used Cerveny 686 which is near perfect except the valves seem very noisy to me. If the horn is in good shape otherwise, can this be easily and reasonably fixed, or are noisy valves (in an otherwise very good condition horn) a sign to look elsewhere?

Thanks