There’s a wealth of free information about fitting on this website alone, let alone across the entire internet. There are many thousands of photos of pro triathletes and pro time trialers that can be studied. Put your bike on your trainer and your camera on the auto setting and snap some photos. Compare them to what you see and read. Adjust, test ride, adapt. See what works for you.
IMHO, bike fitting is an art with dashes of science. The person who will sell you a bike fit for $75 probably knows less about what he’s doing than half the people on Slowtwitch.
I’d be willing to bet that, if you went to 10 different bike fitters, no two of them would result in the same fit. But they’d probably all be within a fairly narrow range that you could rather easily figure out for yourself with a little research. I’d also be willing to bet that, even the best fit of the ten would still yield something you’d feel wasn’t right over time and that you’d end up changing. I know a lot of folks who’ve had professional fittings, some of them by prestigeous folks whose names are well known on this forum. I don’t know a single one of them that rides the exact fit that was recommended to them. There is no miracle fit.
It’s like water spiraling down a drain. You spin around and around the ideal fit and keep changing things gradually and, eventually, you get it dialed in. And when you do, you better remember to write it all down so you have the reference point.
Don’t discount the value of posting your photo and subjecting yourself to the Slowtwitch Forum’s critics. It’s a great freebie. You have to take the good with the bad, but if you’ve been here for long, you probably know who knows what they’re talking about and who doesn’t. Just make sure the photo you post allows people to really see how you fit the bike. The bike should be level (front axle to rear axel). We need to see all of you and, in particular, all the way to the bottom of your foot. We need to see your leg extension at the bottom of your pedal stroke (which is NOT with the pedal at 6 o’clock, but rather is with the crank essentially on a line from pedal, through bottom bracket and up through the center of the saddle). You should try not to pose your photo in the right position, but rather capture it while you’re actually cranking away at something like a race effort. When you try to pose with your leg at the bottom of the pedal stroke, you tend to drop your heel which makes your leg look straighter. Then people will say your saddle is too high when it really isn’t. Set your camera to auto-shoot multiple pictures and keep taking them until you get one that’s right. Your head should be in the position it’ll be in when you’re racing. Don’t post a photo where you’re looking at the floor. If you’ll be using an aero helmet, wear it for the photo and ignore the idiots who think they’re being funny/original when they ask if you always wear it when you ride the trainer.
Adaptation is an important aspect of bike fit that’s sort of a wild card. A fit may initially yield less power, but may be more aerodynamic. If you can adapt to the position over a reasonable period of time, you may end up being faster because your power output rises or because the loss of power is more than offset by the aerodynamic gains. I doubt many “professional” fitters will send you out the door with a fit that yields less power and then tell you to see if you can adapt to it. But that may be the best course, and it’s a course you’ll never find if you aren’t willing to experiment on your own.
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