I posted the other day about giving my 20-year-old Specialized Sequoia a bit of a drivetrain upgrade. Currently, my set-up is a Shimano Claris triple crankset (50/39/30) with a Sora FD 3503 front derailleur, an 8-speed rear cassette (28/11) with a Shimano Tiagra RD 4400 rear derailleur, and Shimano Claris ST 2400 shifters. This gives me a decent range of gearing for someone who is a keen commuting and fitness cyclist, and who frequently enjoys long switchback runs of anything from 12 to 20 miles. I'm not a racer, so am not interested in the more serious end of things components-wise. However, I have found that I'd like to have a bit more at the top-end for downhills and fast flats. I also find nowadays that I can get up most of the steeper hills on my runs whilst staying on the middle chain ring, and without getting out of the saddle. I'll usually switch to the smaller chain ring only if I'm carrying a load in my backpack, or if the hills are over about a mile (fortunately, it's quite a flat area, but we do have a few slopes up to a mile long, averaging around 1:7 and occasionally steeper).
So... I'm now thinking about a more serious upgrade...
I'm leaning towards the Shimano 105 R-7000 set-up, and am thinking that the 53/39 chainset with an 11/34 rear cassette would give me quite a similar range of gearing to what I'm used to - but with that extra at the top end (1:4.82 against my current 1:4.55) and with a lowest ratio of 1:1.15 against 1:1.07... so something I could handle easily enough. This would obviously mean new brifters and derailleurs, too, and a new bottom bracket. The other alternative would be a 52/36 and 11/34 arrangement, but that doesn't seem to offer much more at the top end.
Does this sound like a good and feasible set-up for my current bike? I realise, for the money it will cost me, that I could just go for a new road bike. But I like this bike and am comfortable with it. I'm 6' 5", with a long reach and inside leg, and it fits me perfectly - stack, reach, frame size - so I'm reluctant to change it. Also, I've only been used to a triple chainset before. I know there can be advantages in terms of wear-spread over 3 rings rather than 2, and those micro-adjustments that can be made with the gearing. But, as I said, I've used the small ring less and less over the years. Also, I've nearly always had a bit of a problem with chain rub, in spite of optimum set-up with the derailleurs, cable tensions, and ensuring that the chain, jockey wheels, and cables get changed when they need it. Is this likely to be less of a problem with a 2 to 11 set-up over a 3 to 8? Finally, would I need to change the brake calipers necessarily? I want to stick with rim brakes on the 700/25 wheels I've got.
Any suggestions would be most gratefully received.