News

How do I buy the right-sized bicycle? Understanding the sizing guide

I got all sorts of bikes on offer, including Trek, Scott, Giant, Merida, Cannondale, BMC and more.

BHPian mayankshekharr recently shared this with other enthusiasts.

Hi everyone,

Hope you all have been enjoying the cycling expeditions.

Recently I have been on the lookout for a new bike. Since the new ones had a staggering eye-watering price tag, I went on and started looking at pre-worshipped ones.

I got all sorts of bikes on offer: Trek, Scott, Giant, Merida, Cannondale, BMC and more.

The problem I encountered was that while many of them were in my budget I did not have an understanding of their size chart. The question to the forum is, is there a tool which takes my measurements maps them to the geometry of the bike and tells me what position I would be riding it in?

Here's what BHPian amol4184 had to say on the matter:

Check out any reputable bike manufacturer's webpage for a specific model, they will all have a sizing guide on it. According to your height, those guides will suggest a size most suitable for you. So for example, if you are 180cms, and Trek says you need size 56 Emonda, then you can look up size 56 bikes in used markets too.

I am 182cms and I go for 56/57/58 bikes - there is some variation in the brand's sizing e.g. Canyon's size 54 = 56 of most other brands. While some brands have in-between sizes too like Giant which has sizes like SM and ML. The ML of Giant is 56, while L is 58 as Cannondale, and Trek all treat size L as 56.

Don't sweat it much, check the websites and get an approximate size. If you are really not sure check with a bike shop about bike fit, they should be able to tell you the right size to get. From there onwards you can play with seat height, stem length and height, handlebar position etc to fine-tune the position.

Here's what BHPian Axe77 had to say on the matter:

Hi Mayank.

I’m not aware of a generic site that helps but many big bike brands will have very detailed sizing guides. I know off hand for instance that Canyon will take an entire set of your measurements and guide you to which bike size will fit your specs well.

Having said that, not every bike manufacturer goes into that much detail. My suggestion is to go to a proper bike-fit guy and have him measure you. Whatever bikes you shortlist, share the detailed frame measurements of that bike with your bike-fit chap. He should be able to guide you to the right frame size that will fit you.

Several years ago, the Pune Giant store (which is on the other side of the bridge from COEP) used to have a very good bike fit machine and more importantly a really good chap (Mayur, IIRC) who used to run their bike fits. Perhaps check if that’s still around.

Most importantly, please be aware that bike size can vary drastically from brand to brand and even within the same brand so always test compatibility with a specific brand AND model to see if it's likely to fit you.

Here's what BHPian ebonho had to say on the matter:

On the question of bike size, check the web for the size chart of the particular brand, model and year. If you are on the cusp, size down if you want to ride aggressively and fast, and size up if you want to ride relaxed with more comfort. At 180 cm, I am between 54 M and 56 L for Cannondale CAAD frames. I find the 54 or M suits me best. In most frames across brands.

Some general tips, that are a basic starting point, though not close to fine-dialing your fit, could be (in that order):

  1. You should be able to comfortably stand over the top tube of the bike at the normal position you dismount from the saddle. You will find a variety of opinions on what the ideal gap should be, but you should at least have 2 finger widths or a tad more in my opinion for the safety of your jewels.
  2. You saddle at the right height, you should see a good bit of seat post exposed. This will be more in bikes with sloping top tubes compared to straight ones. But too much or too little is a sign you are on the wrong-sized bike. And of course, you need to have enough length of seat post, with the minimum insertion length inside the frame.
  3. With the saddle sorted, your reach to the handlebar should be neutral and comfortable with a slight bend in your elbows. Neither cramped nor too stretched out. When riding the bike a general rule of thumb is to look down and note the position of your front wheel axle. If it's hidden by the handlebar, chances are your sizing is ok. If the axle is in front, the bike is probably small, and if it's behind, it's probably too big.

Here's what BHPian ninjatalli had to say on the matter:

Others have given good advice so I won't repeat/go there.

I'll just add one significant point - try the cycles. Some shops allow you to do short rides in a limited area if you are committed; others allow you to set up the cycle on a roller/stand and help you figure out if the frame/size fits you. Please don't decide based just a tool-based measurement. Bike fitting is key but when you ride the cycle, then only, you'll realize you actually prefer a particular model/frame more than another one even though both are the right size for you.

Check out BHPian comments for more insights and information.

 
Redlining the Indian Automotive Scene