I just self-measured my cannondale setup, would be great if you could advise on a size/setup for the 8 SL as not sure how it converts:
Road bike frame size 60cm
Pad X = 475
Pad Y = 748
Seat height = 104cm (ground) // 76.8cm (bb)
Lots of good info in here, thank you. The magic (speed, comfort, etc) that you will feel from your new position on the Speedmax will come form the overall movement of "forward and down". Your road bike has your hips well behind the bottom bracket and, therefore, your aerobars up and back. The speedmax will have your hips forward more, nearly over the bottom bracket and because of that your aerobar will be down lower and farther forward. That's reflected in the Pad Y/Xs - the current set up (clipons on a road bike) yield Pad Y of 748 and I suspect you're tri Pad Y position is more like 665. The Pad X on the road bike w/ clipons is 475 and I'm sure you'll be more like 512ish.
You should get the Large for sure (the Medium is close but the Large is better).
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