Originally Posted by
revchuck
Fudgy - You're right, my triceps shouldn't be engaged, but they are. The above photos are from the fit session for my road and TT bikes. Assuming the fit was done correctly, there's no way the back half of my arm could be vertical; I'd be smacking my elbow with my knee every pedal stroke. It happens occasionally anyway when I'm pushing hard.
TR -
The answer, of course, is yes.
I don't notice the discomfort at race pace. The longest TT I've done so far is 20km. The issue is that my coach sometimes assigns me 2-2:30 rides on the TT bike to get me used to the position, so comfort at less than race pace is important. I'm considering raising the saddle a bit since it seems more scrunched than the road bike.
it doesn't HAVE TO take a 2h ride at easy pace to adapt to a bike you ride at threshold for 25, 30', max. just something to consider.
can't tell 100% from the photos you posted, but on the road bike you appear back on the saddle--knee is behind the ball of your foot. that is not wrong, just is. *seems like* you have the same saddle position on the TT bike, but your legs are in the wrong position and i just did a very quick overlay, so i could be wrong. if that is the case, then that is different for how most people who do ~25' events (most amateur TTs) would fit a TT bike. most would rotate up and forward, which would mean your elbows could stay in the same spot, your upper arms could go vertical, etc.
fwiw, i'm not sure that vertical is the goal for upper arms. i like to see it be somewhere between HTA and vertical. there's a bunch of factors in play, including the rider's physiology, handling characteristics of the frame, etc.