I'd actually quite suspicious of your power meter accuracy if 305w gets you 21mph.on a flat. That's really bad and I barely even optimize my aero.

A few days ago I rode the middle 90 minutes of a relatively flat ride at an average of 21.1mph on 251W. Road bike, 6'3", and ~195 lbs. Could be your fit, kit, or PM

I was wearing regular cycling shorts and a jersey, not a race kit but not a loose tee shirt either. When I bought the Tarmac in May, I also bought a Stages crank power meter and had it installed by the bike shop. I assumed it was accurate. Based on my P-1 pedals which I use indoors on the trainer bike, the power numbers on the Tarmac seem accurate.

My FTP has increased from 250 in the Winter, to 275 in early Spring, to now 285. I have been riding a lot and mostly hills and hard intervals. I have about 10 lbs to lose, so my realize that my w/kg is not great.

It's still not entirely clear whether you are using aerobars (which I reckon would have meant replacing the cockpit on your Tarmac since the base bar is probably not round, though maybe I'm behind the times on clip-on tech). And if you are, are you able to stay in them effectively...That's going to make a significant difference. Also you said the 20 min test was windy...headwind? Out and back course?

I was riding the Tarmac as purchased, no aerobars, riding on the hoods like a typical road bike. It was a loop course, but there was not much of a tailwind at all. Part of it was along the ocean, where the headwind was very difficult.

Still, I can't get any decent speed going with the Tarmac. I will have to calibrate my new PM and see if it is working correctly. The bike shop did it for me and told me that I did not have to calibrate before every ride.

What I should do is take my Tri bike (2010 Felt B16) off the trainer and do the same loop and see how much faster I am on that bike in the aerobars, and at what power.

For me to go from an aggressive and what is appearing to be a pretty aero position for road bikes or mimicking a TT position to my TT bike is about 30-40w to maintain the same speed and ~ 2.5-3.5mph

To go from training set up to race set up on my TT bike (kit, aero helmet, race wheels/tubes/tire optimized chain) is ~10-15w reduction

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Brian Stover USAT LII
Accelerate3 Coaching
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