High Tire Pressure

Went to ride today and always before any ride I check tire pressure. Pressures in front and rear were at least 5psi over what the book says. I mostly ride two up so 36 in front, 40 in rear. I noticed that last ride the rear end seemed to be riding very rough. Front rides ok. I let pressure out to specs and rear felt good but front felt a little soft. What could cause this? I've never had this happen before. The bike is kept in a garage and I have not ridden in over a week. I will check tomorrow to see what pressures are set at. Any info would be appreciated.

They will gain if the temperature rises. If the temp went up in your area 5-10 degrees like it has around here lately, I think your tire pressures would increase. I don't know if it would go up 5 lbs. but that's the only thing that would cause it that I know of.

When I filled tires last the temp was around 50deg and then yesterday the temp in the garage was about 100deg. I let air out but noticed that the front felt weird in some corners. I will try a second gauge.

I will just about bet the difference is the ambient temperature.

I had a bad guage once & did not know it until I loaned it to a buddy & he mentioned something was wrong with it a few days later. Tossed it & bought a better quality guage (forget the cheapies by the Walmart cash register).

I always check mine before I ride since they say to check cold, so I would expect it to be higher after being on the road. I have also had tires on one side of a car be higher on the side facing the sun too.