Long Distance Competition/Ultracycling, Randonneuring and Endurance Cycling - 54 or 56 Frame

Hi All. Happy New Years!

I am 5'9". I used to ride a Specialized Sirrus Triple touring bike. Recently, I bought a light-weight road bike that is much more performance oriented. The brand I bought comes in a 54 and jumps to 57. Since 57 is too big, I opted for the 54. Most LBS have told me that I could go with either a 54 or 56. With the 54 my saddle is a good 3 inches higher than the handlebar. I have gone on two rides so far, 40 miles and 32 miles. I guess my question is for those who are my height, would the 56 really make a difference for long distance riding? I only ride on weekends, and I normally do 40-60 miles rides in one sitting with some hills especially on the longer rides. Eventually I would like to ride a century. The 54 compact frame is great for hill climbing, which is what I want, but the 56 may be more comfortable for distance riding. On the other hand is 40-60 miles really distance riding!

Any thoughts would be appreciated.

Thanks

What bike moves from even to odd sizes? I always prefer a bike slightly too big than too small.

Your age as well? If you are young and resilient in the back and neck, the lower handlebars might be fine.

If you are older, less flexible and prefer greater comfort, a larger frame rather than a smaller one is preferably because generally, it places the handlebars closer to the same height as the seat. It means you don't have to fiddle so much with stem angle, length, and height, seat setback, and likely pedal-over-spindle measurements.

There is also less seat post exposed (which can be an issue in flex and if the post is too short, damage to the seat tube).

My now ex-go-fast road bike was a smaller frame than my touring bike, but for various reasons related to fit, I wouldn't consider it for rides much over 160km (I could probably just get away with 200).

The bike I use for touring and randonnees is a much larger frame by comparison, and I can ride that all day, every day for over three days (1200 randonnee) without too much damage to the body.

As sivat says, larger is a better option for more immediate comfort, providing it meets the other requirements in standover height, toptube length, headtube and seattube angles, BB stiffness, etc.

But, if you regard 4-60 miles as long distance and are happy with what you have for its specialised characteristics (hill-climbing) and comfort levels over rides of that length, then stick with it.

the bike should fit you, not you fitting the bike. your position shouldn't change according to the frame. the relationship of the cranks, saddle and bars should basically be fixed no matter whether you're on the smaller or larger frame. on the smaller bike the stem will sit higher on the steerer tube (or angle upwards) and longer length. on the larger frame the stem will be lower and shorter to acheive the same position.

if the small frame is too hard to get into the correct position for you, like getting the bars to the correct height, then it is too small.

it shouldn't make a difference for longer rides if your position is correct. you might leave a little extra space above the stem for a few spacers that would allow you to raise the stem a bit for longer rides, you could also pop on a little shorter stem for long rides as well if you need the extra comfort.

btw, i'm 5'11" and ride a 55 cm frame with a 55.5 top tube