Hills and gear shifting problems

[RoadRaven]

My first thought was what Tulip suggested... have you shifted into the middle of your rear cogs before shifting your front? The idea being that when you change between the two or three rings at the front, you should have the chain in a fairly straight line (that is, if you looked down between your legs to the chain, it would appear to be pretty much parallel to the bike frame itself).

My second thought was are you trying to change gears once the hill gets steeper or as the gradient eases. You can drop your chain when you try to change up or down as you climb.

My third thought was what several others here have already suggested too - cables might need tightening - get them checked sometime soon.

I did have a fourth (and final) thought... but its gone - if I remember I'll pop back into the thread. Obviously I am having too many thoughts this early on a Monday morning!