10 Clues You Bought The Wrong Sized Bike! | MTB Sizing Guide

With all the confusion around long reach and short reach and with bikes now being sold with frame sizing names like “C1” and “S2” or “long and longer”, how do you know if you’ve bought the wrong size MTB? Doddy and Anna are going to swap bikes to show you exactly what that looks like and the effects a wrongly sized bike can have.

⏱ Timestamps ⏱
0:00 - Intro
0:42 - Bike is too small
1:51 - Bike is too big
2:24 - Handlebars are too low
3:26 - Handlebars are too high
4:02 - Saddle height is too low
5:40 - Saddle height is too high
6:47 - Reach is too short
9:32 - Reach is too long
10:40 - Handlebars are too narrow
12:25 - Handlebars are too wide

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[AB-NZ]

For many, choosing the correct size is not too difficult. It’s when you are in between sizes it’s gets tricky and confusing. And if you have a long or short torso relative to your shirt/long legs, then that adds additional complexity when considering seated pedalling versus when in the attack position. Size up or size down? That is a video or two worth considering

[boblipsch]

It looks so funny to see you guys riding on such bikes! So inspiring how you make a video so entertaining every single time!

[Jackpopey]

Found the extremes in sizing a bit silly to be honest. Good opportunity missed to go through some key points between say a medium and a large instead of obvious differences between smalls and XLs

[matt_acton-varian]

This was the video we were all waiting for since the moment Anna joined the channel!

[adventure_hannah]

This is a super helpful video! I work at a local bike shop and trying to explain why proper fit is important has been difficult. Now I've got more information!

[jeremyoiesiuk]

Great video. Very simple and informative! Thanks!

[GabeC]

When I bought my hardtail, I had no concept of bike geometry. Turned out the reach was a bit short. Luckily, I was able to compensate with a longer stem. That longer stem took some getting use to, but it's a much better ride now. 👍

[noureddineelaroussi]

@10:14 Anna said "Longer isn't always better " tell that to my wife please!

[toneloke]

When I first got into mountain biking I got a bike that was too small for me, but it was extremely easy to jump and bunny hop with, like a BMX bike, which was a blast to ride, but at high speeds it was terrifying and sketchy as hell!!!

[toneloke]

My 2018 large yt Jeffsy, is almost the same size as the newer medium jeffsys, you really have to check the reach, and other geometry numbers when you purchase a bike, most of all test ride if you can.

[robertmeyer]

It was like she could make it work, but Doddy looked like a clown on that tiny bike! great visual of wrong sizing, always fun while instilling knowledge!!! Great job guys

[technodrone]

i bought my 6th mountain bike since the 90s this year. my 2nd rockhopper. this one is perfect. i could have went with a medium but large was the right choice. 29 inch wheels make a hell of a difference too.

[georgebailey]

The Thumbnail of Doddy on Anna's bike is hilarious!

[diejeekoen]

OK this is really helpfull. I bougth my bike rather small while I wanted it to be playfull. As I had t put the saddle rather high, the Stack was to low so I put more spacers under the stem, and bougth a higher cockpit. but therefore my reach is now rather short and now you explained that the triangle does not fit anymore whilst standing. On Downhills my legs get very tired while I have to bend my knees to much to not have my arms straigth down. The first thing i did now is to rotate my high riser steerer more forward so the grips move also more forward. The next thing is to buy a larger stem, though they dont sell that lng stemms anymore. I will go von 50 to 70 mm. I think I will feel the difference. I also felt the differnce on my old bike when I changed for a longer stem.

[Marisantos]

I enjoyed this video. I'm 5 ft. tall and;a beginner cyclist and just bought a used but excellent condition bike from someone. Def not doing mountain biking. But this is my 2nd bike so I couldn't understand why I couldn't get it to steer steady but from watching this video I think the saddle is too high for me. Thanks so much!

[Calsonic]

I have made good experience with the size tables which are provided by the vendors.
But i also think it comes to the type of riding you are going for or which matches your style to ride.

[ish]

I feel like the cameraman came up with this idea just so they can see Doddy and Anna switch bikes😂

[Beesa]

I was riding a 15" hardtail which was easy to throw around but a bit 'twitchy', then switched to a 17", not a huge difference but having more room and a longer wheelbase feels more stable. It's a matter of preference, skill and the type of riding you do so unless your bike is way too big or way too small (like in this video) just ride, get used to the handling and have fun.

[zxrboy]

Be worth a vid homed in on between sizes and maybe tweaks to make the bike you have fit better. Maybe even with a volunteer showing the changes before and after?

[ibanez]

As somebody that hovers right around the 5'7" mark, bike sizing has always been a battle. I usually go with medium/17" (even in 29"). Small/15" bikes definitely feel more fun, but I get sore much quicker on longer rides.