I have a 1983 Goldwing Interstate. When i first got it the rear brake pedal would go almost all the way down before any real action could be felt. The pads were good so my mechanic looked it over. he said the master cyl was bad.

he rebuilt it for me and for a time it worked really well. Then while on a road trip it started getting stuck when i depressed it. I would have to use my toe to bring it back up. While on the road i put it in the shop and i was told there was air in the line. So, we bled the system and it worked great. However, the pedal at times gets hard or soft...sometimes seems like it is "thick" going down and coming up and at times seems to have good braking action and other times...not so much...

any idea's?

... Howdy Check And See If There Is Any Road Grime Or Dirt Built Up Around The Pivot Point For The Brake Pedal ... Has The Pedal Been Bent Or Tweaked Some How ... The Come And Go Of The Brakes Might Be The Rebuild On The Master Cyl. Or Air Still In The System ... Happy Trails ...

I don't know if an 83 had linked brakes or not. Either way it sounds like something was't put back together properly.
Could it be the wrong fluid in the system? Sounds like a seal could be swelling.

well, guys, we tore it down the other night and couldn't get the brake pedal off the shaft...with a bit of redneck coaching...we got it off to find RUST on the shaft and in the brake pedal housing. It was dry as a bone also...no grease...so we sanded everything down, greased it and man what a difference....