"Bobbling" hammers on a new Yamaha U3. ( Please help! )

[richard.ucci@att.net]

I would contact LaRoy Edwards at Yamaha before making any changes to the action parts. The man is Mr.Yamaha.

Rick Ucci/Ucci Piano 


> Gordon,
> 
> Did you check for lost motion first?
> 
> I'd guess that regulation will correct everything unless there is actual
> damage to the butt leather. If some hammers are bobbling, that's
> generally an indication of the blow distance being too great. Or the
> capstans are not high enough (too much lost motion).
> 
> Also, checking should be closer than 1 inch, which will also help
> correct the bobbling. Check the capstan height (aka lost motion) first,
> though, as this will have an effect of checking distance.
> 
> I sure would look at everything else before filing the jack top. That
> would be the least likely on my list. Not saying it ain't so, but Yamaha
> has made millions of those things and it would seem we'd have heard
> about from them if there were a problem.
> 
> John Formsma
> 
> 
> 
> >      My first efforts, however ( after regulating the
> > action ) will be to reduce the hammerstroke, and
> > perhaps increase the keydip by 1 mm.
> 
> 
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