Originally Posted by
Barrettscv
It could be a fit issue. The Tarmac appears to have a large saddle to bar drop. This can restrict your ability to breathe fully, reducing your oxygen intake. That will tire you quickly.
I finished the fit thing. I've been working on that since January. Did one final adjustment yesterday. It felt good on today's ride. Just wore me out. And my average speed was slower than on the Litespeed.