i was professionally fitted about 3 years ago. since then, i've always had my bike set up the same way. i have no pain issues, and my pedaling style is quite good... i seem to spin well at a range of cadences. it's comfortable too for rides up to 7 hours.

however, i started commuting using another bike, which had the seat post higher. i felt way more powerful on it because i could actually leverage well enough to get a powerful downstroke, but i felt less "fluid". and now when i go back to my main road bike, i feel smoother... but weaker.

so, is there a certain compromise that must be made here? can you have it both ways? (i would experiment a little more with my road bike...but alas, the seatpost is frozen! )

thoughts?

Well first, just becuase you "feel" more powerful on the other bike doesn't mean you actually are.

If you really care, set up a series of time trials, or get / borrow a powertap and measure for real.

OTOH, lots of guys would give their left one for a bike they're comfortable on for 7 hours.

Moral of the story: don't go making changes based on "feel" alone till you have more facts and experience.

Now re: seat height, it's frequently true that a higher seat will allow you to generate more power. At some point the tradeoff will be injuries / strain / discomfort. So "optimal" varies from rider to rider to rider and situation to situation. You could get away with it on the commuter for 30 mins at a time, but try that for 7 hours and you might be a spasming wreck, see?

^^^And given your screen name, I'd be inclined to pay attention to what you say!

Don't be deceived by what you think is generating more power.

I've been working with my cadence and wattage lately and am consistently surprised at how shifting to one lighter gear and slightly raising my cadence increases my wattage although the power I feel I am generating seems lower.

Comfy for 7 hours? Don't mess with that without hard numbers.

yeah, you guys bring up good points. i guess the complex part of the question is: do i fit myself based on the longest ride i sometimes do? or do i fit myself based on the ride that i do most often?

because i rarely do 7 hour rides, but i do a ton of 1-2 hour rides.


[edit] - i really feel like i need two different fits depending on what the ride calls for. is this unheard of?

You should fit yourself according to comfort and a powermeter.

Raising seat height might make you feel stronger, but your cadence will drop. Lower seat height allows more spinning. I've realized that I pedal a lot with my ankles pointed down for a large part of the pull up so my heel is never really flat at the bottom. I adjust my height to where I don't feel like I'm being lifted off the saddle when I pedal. It was working well when I was riding (on a hiatus due to injuries from a nasty wreck), and I didn't have issues with my knees though I had lower back pain.

I'd say if it works for 7 hours, don't mess with anything unless you're getting a power oriented fit getting done by someone who knows what they're doing. We like to tinker too much, don't fix it if it is working as well as it is. If you do, only do it to one of your bikes and make sure to mark everything before any changes!