mooder

Hey,

I thought my ideal size was 54 cm. I bought in 2012 a 54cm bike (used 2008) and in 2014 a 53 cm bike (used 2008 - I got it for super cheap). Now I just checked again and it seems like for a 179cm (+- 1 cm) height and 85-86cm inner leg, a 56-58cm frame should be best. I went to some bike shop and effectively, they suggest a 56cm frame (L to XL). Although, one said I could still adjust the bike to my size even if the frame is smaller.
Should I sell my current bike and switch to a 56-58 cm frame? How do you determine the exact frame size. It seems that the bike size proposed in LBS largely depends on their stock availability.

RoadGuy

Depending on how the bicycle maker designed and built the bike, you may need a different size bike when riding different brands or models.

Which is why it's important to try riding different size bikes when shopping for a bike. Sizing charts can get you an idea of what size bike may fit you, BUT a test ride is the only way to know for sure.

I have been riding 56cm and 54cm conventional (horizontal top tube bikes) for over forty years. Never really tried compact/slant top tube road bikes before. I've tried 52cm bikes in the past and they were way too small. Recently I bought a 52cm Felt F90 with a cracked headtube to strip for parts. It's an attractive looking bike, and I tried riding it to see how compacts ride. I was surprised to find that the reach is actually longer than the reach on my 56cm Trek bonded aluminum bikes. It actually fits me pretty good, and I can ride it without feeling cramped in the cockpit.

Fit fit is a combination of the standover, reach (distance from the seat to the handlebar flats), and the drop (distance from the height or the seat to the handlebars), when the seat is properly positioned for the legs (height of seatpost/seat and the fore and aft position to provide the correct leg extension length, and knee position (KOPS to start, knee over pedal spindle as a basic position).

The way I see it, people can usually ride three sizes of any model bike. There is the optimal size, one size larger, and one size smaller. The optimal size frame is the one to shoot for in most cases (unless you are young and growing (or older and inbetween sizes). If you get a bike that's slightly too small or slightly too big, by changing seats, handlebars, stems, and cranks you should be able to achieve an acceptable fit, the same as if you have gotten the optimal size frame. If a bike is two sizes two small or two sizes too big, I'd keep looking if you are looking, or sell it and get the right size if you already own it.

If you don't think you know enough to get a correct fit, you should consider going to a bike shop with competent, honest employees who can help you determine your correct sizing.

And yes, some bike shop personnel try to fit you/sell you whatever size bike they have on the floor, whether they have the right size, or not.

mooder

How do you determine the correct reach? i.e. the proper distance between the seat post and the head set or stem? I've read that the back has to be round. So far, I adjusted my bikes according to the Holmes method but couldn't find anything concerning the reach.
I have to say that I feel some what comfortable on the bikes, no back pain since I used the Holmes method.

rms13

If you're comfortable on it, it fits

caloso

Normally I'd say a 56 is right for you. I'm 1 cm shorter than you and typically ride a 54 with a 110 or 115mm stem, but I have short legs and prefer a shorter headtube. It's obviously easier to embiggen a small bike with a longer stem and more seatpost than the other way around. If it fits, there's no need to sell anything.

RPK79

You can always shorten the frame with some duct tape, hacksaw, and a broomstick (for support).

redfooj

Translate your bike dilemma over to buying clothes.

Are you a small, medium, or large? Depends on various body metrics -- weight, proportions, not just height. Depends on the manufacturer. Depends on the style -- manufacturers intended style in addition to your own.


As 1 point of relation, I'm 177cm and currently own a 54, 55, and a 2-56cm advertised bike. They all fit perfectly and set up to have identical contact point and geometry. (55 is my favorite but for personal reasons)

MagicHour

I'm 2cm taller than you with a similar if not slightly shorter inseam and 56 generally works for me. In your case you have the inseam to take the larger frame, but it depends on the reach and stack, and whether you will be too stretched out, or not if you size up? As a ballpark you probably want to run at least a stem 90-110mm for 54-56 sizes, so you want to take that into consideration too, i.e. if you need to go down to a short 80mm stem on 56, might not be ideal, likewise a 130 on 54 would be extreme (unless you're a pro rider!)

rms13

I'm 5'10.5" which I believe is about same height as OP. I currently have 2 54cm bikes with 120mm stems that fit me perfectly. In the past I had a CAAD9 in 54cm with 120mm and it also felt great. I had a CAAD10 in 56cm and I TCR in M/L (approx 56-57cm) and those felt too big. But obviously differences can be made up with stems, seat height and fore/aft etc but I like the way the smaller frame with longer stem handles

mooder

I have a 110-120 mm (using a ****teley tape) stem and I feel like I wouldn't enjoy a longer stem.
I am considering trying used 56cm bikes for sale and see how they feel while taking measurements for comparison. Now that I have ridden the 53cm and started to notice that I would enjoy a longer stem. I also feel a bit too close to the handlebars. I will probably put it for sale! I don't mind too much as I paid it 360$ with a 105 groupset. The used market seems to be so inflated lately. I hope I could sell it for 750$. I put a lot of work on it and improved the look quite a bit.

johnyguy

Wrong post

ColaJacket

I'd say to go to several LBSs, and ride several bikes in sizes that are close to your size. Bring in your current bike, as it could help the LBSs find similar bikes.

After riding several bikes for 10-20 minutes each (unless you can tell right away that the bike is the wrong size), see how those bikes feel compared to your current bike. If your current bike feels more comfortable than any of the new bikes, there's no need to buy a new bike. If one of the new bikes feels better than your current bike, then it may be time to get a new bike, depending upon how far off your current bike fells.

If you go to several LBSs and let them know you trying to find a bike with a better fit than your current bike, they'll be less likely to push a clearance bike on you, just because they want to get rid of it.

Also, have you considered getting a professional fit? If you've been riding for a while, you can help a professional fit you. They can also tell you if your current bike(s) are too small for you. And they may be able to help you make the current bikes fit you better.

GH