MarkUK82

Hey all
Im new to the gravel scene. Just wanted to ask a question about sizing for gravel bikes. I’m 5’11. I ride a 54 specialized allez sprint with a 130 stem. I guess you can say it’s a small frame for my height but it works for me and it’s just a racing bike... so I want to get a diverge. I dropped by the bike store. They said don’t get a 54 like your allez sprint. The 56 is a great size with a 100 or 110 stem. I’ll be more upright. Comfortable and great for adventure... camping or some fun technical trail.

I did try both. Honestly. I couldn’t tell the different because they made the positions the same.. just the 54 was showin a lotttt of seat post. They said I looked better on the 56.

In my head i want a 54 because I’m use to that...but.. I don’t want to regret this. Maybe I should go with a 56 as it is an adventure bike not a racing bike. The 56 isn’t big. After all I’m pretty much 5”11. Most people with my height ride that size...

any info would be great. I don’t know anything about gravel.

HTupolev

If you can achieve the desired fit on both, it really won't matter much. The smaller frame will make it easier to err in more aggressive postures later, the bigger frame will make it easier to go less aggressive.

Note that "size 54" is a very rough description of fit; it doesn't mean exactly the same thing across bikes and is an imprecise craft.

Koyote

Other things equal, I would agree with your shop. A 130mm stem is pretty long for a 54cm bike, while a 100 or 110mm stem is pretty much a normal size for a 56.

Is the stem slammed on the 54? (Meaning: is it mounted right on top of the headtube, with no spacers underneath?) If so, make sure you can get an appropriate handlebar height on the gravel bike. If not, then that is another argument in favor of the 56.

RideMyLeMond

I'm 5' 10" and ride a 54cm Diverge and I sometimes have an issue with toe to front wheel clearance when the crank is at the closest tangent point to the wheel so you may want to consider that. I ride with size 44 shoes, so if your feet are bigger this may create an issue for you as well with the 54cm frame. I've learned to avoid that scenario when stopped at a light or whatever so you may do that too.

I upgraded to a better 6 degree flared Hover Bar in a 44cm. The 54 comes with a 42 and I prefer wider, and on gravel wider gives you better control. Do you need wider? Does the 56 also have the 42 or does it come with 44?

MarkUK82

The 54 isn’t slammed. I have a few spacers. I think there is around 15mm. When I was getting fitted at the bike shop for the allez, They bike shop said. If I went 54 I could use a longer stem but not slammed. If I went 56 allez I could use a shorter stem but slam it. When I was fitted on the 56 diverge, the shop slammed it as much as they could.. there might be a 5mm spacer then the shock system.

RideMyLeMond : the 56 comes with a 42 width bar. The shop also said to upgrade to a 44 at some point. I’ll probably do that.

mstateglfr 

I am not sure what the benefit of a 54cm frame is at your height.

In terms of important differences...the frames have 4mm of difference in trail, 20mm of stack difference, 6mm of reach difference, and .6deg of head tube angle difference.

If you can't tell the difference with any of that, then go eeny meeny mint mo and pick one, I guess.
That bike is designed with a massive amount of stack across the board and some serious BB drop. Interesting design choices.

Lemond1985

From your description, the 54 would be great for your height, current weight and current level of flexibility. I'm 5'10" and used to ride 54's and 55's, until I lost weight and got serious about stretching and flattening out my back. Nowadays, a 57 cm is perfect, and I ride a 130 mm stem. There is absolutely no way I could go back to a 54 at this point.

So the 56 cm frame would be a frame you might "grow into" over time. Even a 56 seems a little small, Armstrong is your height, FWIW, and I believe he rode 58's for most of his career.

I'm sure the 54 would be fine, but I myself cannot stand riding a frame that's too small, so these days I err on the side "a little too big" when shopping for a frame. YMMV, but I have always thought it to be easier to make a frame that's slightly too big to work for me, than one that's slightly too small.

MarkUK82

At the beginning of your quote you said “the 54 would be great for your height “. Did you mean to say 56?

Lemond1985

No, if it fits you, and "feels right" what more could you ask? Fit is everything, and some people like smaller frames because they climb and sprint well. I'm just saying that a larger frame might be more versatile over the years if your riding preferences change.

Some people your height can fit on a small frame, it's not that unusual. I was just pointing out that for your height, a 54 does seem a little on the small side, from my POV, since I'm an inch shorter and ride 57.

MarkUK82

So I went with a 56. Pretty happy with the size. I think 54 would just be a bit small and unstable in technical areas.

Just got the bike home. Took the stickers off. All the stickers are sun bleached. Ugh..... what the heck specialized. ☹️☹️
I have a permanent frame sticker on the bike shaped like a shield

mstateglfr 

Not sure what I'm looking at