avc465 

Found a perfect vintage Italian SLX frame at 53cm seat tube and top tube. But the million dollar question is will it be the right fit?
I am between 5'5" and 5'6" and I have around a 29" inseam. For a while I thought I needed a 50cm frame but after long online research it appears that 53cm might not be too big.
I currently ride a track bike frame which its geometry is super tight and not comparable to a road bike. So would love some input if you have any!

Thanks!

Iride01 

What is the manufacturers suggested sizing guide? If you've no experience I'd go by that first. I know you said vintage, but for many vintage bikes you can find on the web where someone has scans of the catalogs for each year. Some brands did have a page about sizing.

Otherwise, consider the reach to the bars both on the hoods and drops. The standover height with the top tube...... more important on vintage with the horizontal top tube.

And consider how much drop you think you want to have between the saddle and the bars. Saddle height generally will be the same for every bike from the pedal at it's bottom stroke. So a larger frame might not let you get as much drop as a smaller frame of the same model.

But all models and mfrs can be different geometries and tube lengths. so a 53 cm in one model might not be a 53 cm in another.

Carbonfiberboy 

I think you might find it a little big, but not too big. As above, set your saddle height off your current bike, measuring pedal to saddle top. Then see how much exposed seat post there is. I have ridden bikes with almost no exposed seat tube, but about 4" is a good normal. Take it for a ride, see how it feels.

berner

I agree with Carbonfiberboy that you might find it a bit too big.

avc465 

Thank you fellas! Yeah I'm gonna pass on the 53cm. Found a 51cm thats better fit for me with a 52.5cm top tube. My only question now is should I go 80mm or 70mm quill stem? Just thinking with the hoods i might want a shorter stem. My handlebars are Nitto Noodles FYI.

Thanks!!

Iride01 

Get a quill adapter so you can put a pista/threadless type stem on it and then you can more easily change stems out to experiment with different lengths.

I did that on my older bikes and it's nice not having to remove bar tape and levers to see "what if?"

headwind15

I have been road cycling for over 40 yrs, I was a shop owner for over 12, a frame builder since 2000 and am 5'-6" tall (or short). The thing is that people used to ride bigger bikes. I recommend you check out you tube under 1936 Tour de France. You will notice that no one has more than 2" of seat post sticking out of their frame. I bought my first real road bike (A 52 cm Cinelli) in 1976. I could ride that big of a road bike and I did, so yes short people can ride relatively large bikes. I am not even saying that I would have gone any faster with a shorter bike. But... it is simply nicer to not have to straddle a bike that feels like it practically comes up to your belly button. After getting into this whole "compact frame" geometry (it's been around for a while now.) I ride a road bike with a 42 - 44 cm seat tube. About 10 cm / 4inches shorter seat tube than my original Cinelli. The top tube length is only slightly longer to help get away from so much toe overlap. The bottom line is that there is no benefit to having a high top tube, but major benefit of a lower one. I do recommend that you try out a giant with a 44 cm seat tube and see how you like it. There is no way you will digress by riding some behemoth 53 cm frame, trust me.

Alexthe

Hello headwind ,

I felt a strong impulse to respond to your story because it is mine too !
but, I am still riding my large bike , and have yet to own a smaller sized one . I am exactly your hight and the bike is a Motobecane Grand Jubilee 1978 of 52cm .It was my father's bike and remember the day as a child seeing him happy and impressed by this new thing riding it around the block on east 71st in manhattan were we lived .I would change the bike for a Masi or something like that maybe, or I love even older french bikes , but I am fond of it pretty much and the Moto has so little resale value I would have to dig in to other funds . I am experiencing a lot of riding now more then ever before because of the lockdown . I am dressing this thing up like you wouldn't believe.with a Gilles Berthoud saddle and tool bag simplex chain guard Rene Herse type black fenders (bike is metallic red ). What would be your advice on Seat post height or another seatpost or a special castle,that possibly brought this seat forward? Also should I modify anything else like handlebar geometry? Change the stem? I'd like to make the best of what I have for now , that I can . One day the accessories can be removed and put on another bike . Oh one more thing, I'm a 30 inseam with good proportions not short for my size ,in arm length too.
Alex

headwind15

Hi, An older Motobecane like yours may have a shallow seat tube angle, so you may find it useful/ nice to use a zero offset type of seat post, where the seat rails are not set back 3/4" (like on a traditional type) I do not know where you live , but I have had relative success with finding affordable short/ small used road bikes on Craigslist. I bought one from a lady who had basically ridden her 43 cm (they don't offer them in that size anymore) Windsor tourist around the block a few times for $200.