Originally Posted by randall t
check your brakes, one might be rubbing,or if a wheel gets out of true the tire might be hitting the frame,or just one of lifes cycles where you have a little low spell,lose sleep lately? could just be the change of weather, this time of year the days start getting shorter and i find myself wanting to scale back on my training,and my mileage drops, dont get depressed about it,give yourself a mental break and ride a different route,and dont care about how long it takes,as so many things in life it will pass
This is good advice, and since it is ben raining a lot in your area it is easy for your chain and gears to accumulate a lot of grit which can slow you down. Your pannier may also be a factor since it is on the back of the bike you are pulling more weight. It really shouldn't be a major factor but it could be one or all of the above situations. I would give your bike a good once over.