Have the keys on your Yamaha Clavinova electronic keyboard started sticking in the down position, or lean to the left or right? If the answer is yes, then is likely that you have one of a rough batch produced using the wrong kind of grease. Yamaha have been quick to recognise this problem and are offering a FREE repair of your affected keyboard. Even if the equipment is out of guarantee, or warranty, or has changed hands from the original purchaser.
All you have to do is contact your local Yamaha service engineer, just make sure he's qualified for keyboards and not motorbikes.
Surrey area : Mike Barden - 01483-236161