How to Choose The Correct Bike Size

Choosing the right sized road bike is essential. James and Chris explain how to chose the right frame size as well as how subtle changes to parts of your bike can affect the way it feels and performs when you're cycling.

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Frame size, stack and reach as well as adjustment to the saddle and handlebars all have an impact on how a bike feels and handles. This video helps shed some light on all of these things to help you make the best decision when deciding what size is best for you.

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Music - licensed by Epidemic Sound:
ES_Waltzer - Dye O.mp3

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[johna]

Bike size has been a U shaped curve for me - when I started, I went for a smaller size because I felt too stretched on a larger size. Then, as I did more cycling, I needed a larger size to be comfortable. Now, as arthritis sets in, I went back to the smaller size and more upright position. Which is why for new cyclists I suggest buying a second hand bike, so when you decide it's the wrong size you don't lose too much money due to depreciation!

[jirdesteva]

And I thought I was confused about bike sizing before watching this video ?! :P

[buckroger]

I thought the correct size was which ever one looks the coolest.

[dennishaughton]

I am a runner. Me knees have taken a serious beating over the yrs. So @ this pont I'm contemplating on crossing over to cycling. I had no idea how big cycling really was. & yeah how expensive & technical it can get to purchase the right bike for u. This video certainly helped in my search of understanding the cycling world.. thank u

[danielbum]

Buy two sizes too small ✅
Seatpost extended all the way ✅
150 mm stem ✅
You now look like a pro ✅

[luckymouse]

When your bike is so light, you can keep it from falling down by placing a bidon next to it.

[annettefournier]

I need the T-REX size. Inflexible back and short arms.

[starving_drummer]

Could you please make a video (or even a small series) about how road bike frames evolved through the histroy? How frame geometries changed and why? What kinds of fits were preferred by pro cyclists historically and why and by whom those preferences changed in time? (ie: Old steel frames always had top tubes parallel to the ground, nowadays they're mostly sloped. Or saddles are adjusted much higher than before, etc.) I couldn't find a comprehensive well made video on that subject, so I would really appreciate if you could make one.


Keep up the good work.

[michaellynn]

At 6 feet 3 with a 94cm inseam, I settled on a proportional 59cm Viking (I now ride something a little more sophisticated) which seemed to fit perfectly actually, though higher end bikes aren’t always proportional. Always aim for a size that allows you to get an efficient pedal stroke, otherwise your fitness is going to be impacted, unless your riding for leisure only. A smaller frame (assuming you’ve got the seat at the correct height) will produce a more aggressive position, a larger frame size with the same saddle height will give your a more comfortable position - assuming there isn’t much difference in the top tube length, which based on charts, experts and forums, increases by 1cm for every 2cm seat tube increase.

[nautastro]

I got 2 size up with long wheelbase hybrid... everything is adjustable in wide range, after some custom parts added. Currently planning to install pedals lowering joints to get better pull and also to lower my seat all the way down, that way my feet be able to touch the ground when I stop. I like my setup . With big tires it looks more like a motorcycle to me.)) Sweet big bike

[johnsonjae]

I always have this issue. I have a long torso and short legs. My legs would dictate a medium frame should be big on me, but my torso and arms are comfortable on a large frame with 120mm stem. This gives me ideal stack and reach dimensions that are nearly identical. The issue comes when I wanna get long and low, and my head and arms are still above my hips on a large frame or chest on the handlebars on a medium frame. I have considered using my experience as a welder to make my own frame and bolt existing components to it.

[Wyoming]

Now we need a video on how to apply these bike measurements to individual body measurements.

[jamesainsworth]

There needs to be some personal choice options considered when choosing your frame size. I've just ordered a new bike that offers a S, M, ML, and L sizes. According to the manufactures sizing chart, I overlapped the M and ML size so I could go either way. Being someone with a longer torso, I'm able to have something with a bit more reach. Being an older rider, I also didn't want to be too low in the front in order to prevent back discomfort. I made sure that I sat on both sized bikes to get a real feel. I also compared the geometry of my existing bike to that of the new bike, to make sure I was aware of any differences and made sure there was enough adjustments in the saddle height, etc on the new bike to be close to my existing set up. I went with the ML. For a younger racer, I could see why they might go for the M, and have the seat post way up and the bars slammed down, but for me it just felt too small.

[angeloparagoso]

Now i know the differences... I love to go back in cycling after i saw this video... Thanks for the info...

[debbieschwartz]

I use a professional fitter when deciding on a new bike. He has all my measurements and helps me make the correct choices. I bought my Niner gravel bike that way. Most comfortable bike I own

[rah]

So much easier to make an mountain bike fit.
Have one hardtail and one full suspension bike.
Both fits me like a glove, super comfortable.
The road bike was much harder to fit, and is still not nearly as comfortable, but then again I'm not so flexible.
This winter between riding my full suspension with studded tires I will start streching out my body.
Now I can just barely touch my toes from a standing position, I'm sure if I become more flexible my road bike will feel much better to ride.
The size of my road bike seems good, I'm at the upper limit of my size falling almost between two sizes with 3 cm to go.
Not my bike size that is the trouble is my body, lifting weights for years without streching out will do that to you.

[andy_xtr]

IMO Bike size and especially bike fitting is everything. Get it wrong and you can cause long term injury. I learn't the hard way!!

[jkdjose]

1 size smaller than what dealer recommends is ideal for me… dealers tend to go to bigger size and that’s wrong

[jpiccari]

Wow that stack and reach graphic was less than helpful. For anyone wondering, stack is the vertical and reach the horizontal.

[jhjbarnes]

This is a really valuable subject for a video, so thanks for making it. I think it could do with being a bit more precise with the graphics though, and use real examples as someone else also commented. Another thing that was not mentioned is seat-tube angle - this can obviously have a big effect on the rider's hip angle and how far they have to reach, and is not made clear when looking at stack and reach alone. Not all manufacturers make proprietary seatposts with different offsets.