So what I have gleaned from the wisdom offered above:
– Best place to lose weight is wheels/tyres providing the new ones are actually significantly lighter than the originals.
– Carbon cranks are expensive and don’t add up to a big weight loss.
– Other components (stems, bars, seat posts, pedals etc.) all add up so a few grams here and are worthwhile but the costs ramp up.
– Lose body weight (but it isn’t the same as a light bike).
– Spreadsheets.
Thanks all. I think I may get some new wheels and shave some extra grams off with a better chainset and pedals. Forks are heavier because I replaced the knackered Rebas with some Pikes. I shan’t be going back again! New bike costs circa 3k. I reckon I can do the wheels and bits for around 1k and they’ll be transferable to nearly all the other bikes in the garage too.
Time to get spendy!