[Alan Brinton]

It is very common for older model Yamaha Pianicas (especially 1970s-80s, but even 1990s) to have sticky keys. I have quite a few vintage Yamahas, and I sometimes play them. I have gotten in the habit of running my thumb, finger or palm up and down the keyboard a few times with those models and even sometimes with fairly new ones, after which there’s not a problem that is noticeable to me. It just becomes part of the routine when I pick up a Pianica. So much so that I sometimes do it with other melodicas, loosening up the keys, like “warming up” routines that we see musicians doing with other instruments.

The phenomenon I’m talking about involves a little barrier of resistance that you have to break through, most noticeable when the keyboard hasn’t been played for a while. Maybe that isn’t what you’re talking about. The amount of resistance you feel can be adjusted somewhat: increased by shortening the key’s spring (on a Yamaha or Suzuki), decreased by stretching the spring. I probably would like a little more resistance from the keys in my Suzukis, but I haven’t experimented with that. It would involve clipping a coil from each spring, and then if necessary stretching it just enough to get to the level of resistance I’d like, which would have to be done uniformly for all the keys, best done using a measuring instrument.