This may be the second or third “suggestion” to lose weight. While I’m guessing it’s people being a bit snarky, you can save it. I’m a competitive age grouper that is as light as I need to be to race well. Any lighter and I’d risk sickness or injury in my experience. 6’2” 75kg. I’m racing better being stronger.

Crank length difference isn't trivial for some people, and it definitely changes your gain ratio. Your 39/28 on the Cervelo is an "easier" gear than it is on the Trek.

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As Fredly said, I really think it's the crank length. I had 172.5 on my tri bike and it never was a problem riding the 6 gap route. One year during the offseason I switched to 162.5. Never really noticed a difference on the routes that mirrored tri courses but when I took it back up to the 6 gap route or anything with a steep or substantial climb, I was dying. Now I take my road bike out for those routes.

Get stronger legs.




Seriously though, no way that weight difference is a performance problem.

You are my size...and I wasn't being snarky. SC, and I have the 2019 SC, are not built to be "light". Can you make them lighter? Yes, but can you get stronger, lighter, faster, more aero or whatever instead? At a point bike weight stops being the issue because you can only get it so light. Functional weight matters and its a trade off. Sure you can make your bike lighter when you don't add water bottles but at what cost?

However if weight is an issue you can lose a lot of weight by using lighter wheels.

Just my opinion, but bike weight in triathlon is really underestimated. Obviously you need to get your own weight down for climbing purposes, but
once your weight is optimized then you have to consider how heavy your bike weighs. A lot of folks are saying to just lose a pound or two to make up for a bike that’s a couple pounds heavier. It doesn’t work that way though. You have to get your weight up climbs and the weight of the bike. They’re two separate objects. Sure it’s combined weight, but in actuality you are propelling the bike forward so overall the weight of the
bike that you are powering up a hill is somewhat mutually exclusive of rider weight. If I drop two pounds then my watts per kilo has to increase to power that heavy bike. As well, a heavier bike is a big assist on flats, descents and
in wind. You’ll have more momentum and extra weight will carry you longer. If you’re riding a lot of hills a lighter frame will help a bunch. If not, then a heavier aero frame may be more beneficial. Finally, I think your body weight is fine. You don’t have much if anything to lose.

I agree if everything else is equal....pretty much what you said. IM Canada would be a good example but for the most part and "generally" speaking for the "masses" there are not a lot of hilly races that weight is a big issue.