What bits to upgrade?

Quirky
Quirky Posts: 123
edited April 2011 in Road buying advice
I have a 2009 Specialized Sirrus expert and I'm going round in circles thinking about upgrading it.

It needs a new chain and I'm thinking at the same time it might be worth upgrading the whole drivetrain but this is where I'm having problems. I would quite happily upgrade the whole groupset but it has flat bars so I'm limited to what shifters i can use which seems to have a knock on effect on everything else.

What should I replace and what should I keep standard?
weight.png