I've encountered some problems on the repair bench with weighted keyboard actions that were left in cars at both ends of the temperature extremes.

Don't do it.

I think its okay to travel with them, just don't leave 'em in the car overnight or all day in the cold extremes or out in the hot sun in the hot climates.

The rule of thumb for *any* instrument is to never leave it somewhere that you yourself couldn't survive...


--Mac