pdxtex

How much wiggle room up or down do you think the average person can get away with? Suppose you ride a 60, would a 56 just be too small even with the "proper" seat and stem/handlebar adjustments? I've never really taken geometry into account and Im from the old school philosophy of if the top tube doesn't ram your nuts when you stand over it, then you are good to go.

oldbobcat

If you normally ride a 60 that's too big for you, then a 56 might be just right.

Every day I meet riders who are perfectly blissful riding bikes that don't fit. Instead of guessing, or asking us to guess for you, why not visit a shop and get fitted, or at least get sized, by someone who can observe your height, your proportions, your posture, and how you sit on a bike.

StanSeven

If you have a smaller bike, it's easier and possible to adjust. In fact many of the pro's ride bikes smaller than the typical fits process suggests. You can raise the seatpost and use a shorter stem with a different angle. But if the bike is too bike, the adjustments are more limited. Plus a big bike feels like a boat in handling.

Jfitalia

I just recently went in and got sized and from my experience each company fits a little different. Some bikes I was comfortable on a 50 or even 51 however at 5'5" i settled on a 49 tarmac

boze

If you let me change your original proposition to read, "Suppose the right size is a 60, would a 56 still be too small even with adjustments?" then my answer is "yes, it would absolutely be too small." Nobody who fits a 60 should get on a 56 and try to make it fit with extreme adjustments. One size (e.g. 58 to 56 or 60 to 58) can potentially be within the range of what fits tweaking the reach and so forth, but that's it. By definition, two sizes apart (e.g. 56 to 60) can't be a toss-up for fit because there's a size in between them that would do better than either one.

rishardh

I think the more important number to look at is the Top Tube length range you can get away with. To do this you should have already been professionally fitted or have been riding for a while and know what works for you.

pdxtex

yes, i should have stated that i know my proper frame size is a 60 cm and how much smaller could i go? so that being said, wouldn't a set back post and a longer stem basically equate to a larger frame? i see lots of good deals for 58 to 56 cm bikes on my local CL far more often then 60 cm ones....

Velo Dog

If you rode a 65, you'd NEVER see a good deal. You'd barely see any bikes.
That aside, though, after decades riding 62s (because that's what shops had) and even one 60cm frame ("We'll make it work. We'll GIVE you a longer seatpost"), I finally nutted up and paid full price for a bike that fits. The difference is considerable. Now that I'm attuned, I see a lot of people on bikes that look too small (foot-long seatposts waving in the air, etc.). I'd be wary of smaller sizes. You can compensate to a degree, but not always completely.

reef58

As long as you don't mind an increasing saddle to bar drop you can make a smaller from work to a degree.

TheRedWolf

I've been riding a Specialized 56cm for several years, last summer I started looking at upgrades and first comment from LBS was "I'd never put you on a frame that large". 54cm was great and with proper adjustment, I could probably ride a 52 (I am 5'7"). But I kept riding the 56- probably does handle like a boat relative to a better fitting bike, but it's all in what you are used to. I've been riding a folding bike (Bike Friday) for last several months- very different fit but you get used to it, and I ride it daily.

My point is that I think bike sizing can be over emphasized. It's not like a shoe that is too large and will give you a blister as your foot slides. If you are comfortable and enjoy riding- not just on a short test ride but after hours on the bike- I think you can adapt to +/-1 frame size. There is no right answer, it is very individual.