Originally Posted by
LibertyFLS
I can keep up everywhere except when we get to the big climbs and then my 24 tooth rear maximum on a 40 something front just simply doesn’t allow me to hang with the guys that have such a wide range of gearing.
...
I’m also 50-something and very fit, lift weights & cycle so it’s not trying to keep up with fitter people.
Lots of good advice in-thead, but I want to focus on this.
If you are keeping a reasonable RPM during these climbs, and are dropped as you're out of breath, a new bike is unlikely to help unless the bike+rider weight goes down by a significant fraction. You need more watts/kg.
If the others are at a reasonable RPM but at a speed where you need to stand to keep the pedals moving (or are inefficiently mashing slowly), then I think you need lower gearing, not necessarily a new bike. Even a 39/28 (1.39) is dramatically different than a 42/24 (1.75). That would move a 40rpm effort to 50rpm. And 39/28 might well be possible with your existing rear derailleur and crank set.
Tons of "lower gearing" threads exist to search through.
[Note that I'm assuming good maintenance, fit and positioning. There are stories of massive speed increases with a new bike; only possible if the old had some massive source of friction.]
I did find that when I ride with stronger folks, and am mostly drafting, that reaching for the downtube often leaves me gapped by a half bike length. If I suspect I'm the weakest of the 2-4 riders, I'll typically take my brifter bike, even though I'm faster solo on the Ironman.