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I've been thinking of getting an MTB. Watching all those videos on YouTube of people doing cool stunts or even just riding in a forest off-road looks amazing - until I got to videos like this one:

I've seen lots of posts on how to prevent breaking a bike frame, and I completely understand that the maintenance of bike should be regular, but are all these broken bike frames only because of bad state of bike itself?

I've got some friends who have broken their new MTB in few weeks of riding, was it just coincidence?

My question is: do bikes actually break that easily? That may sound like a noob question because, yeah I am not into biking at all. And I am looking at getting an MTB. (I can drive bikes pretty well, on roads.)

Thanks for any comment, answer, upvote or downvote (oh and yes if you downvote tell me why so I wont repeat my mistake)

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    I wonder how many of these failures are "assisted" purely for the video. – Criggie Dec 30 '17 at 0:22
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    Many of the frame failures in the video above involve accidents and serious forces (hanging up the rear wheel really badly, landing nose heavy with lots of momentum, or crashing into a tree). Modern bikes are built pretty solid, however there are manufacturing defects in some frames, and even flawless ones will break if repeatedly abused in the way shown in some fails in this video. Quite a few in the video do also seem set up (e.g. bouncing in the garage, probably on an already cracked frame.) Also no info on how old and abused the frames are or types/frequency of previous bad accidents. – Purr Dec 30 '17 at 3:38
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    Key thing is your assertion is 'so easily' - those guys were not riding those features for the first time, and I bet the bike was not either. I would put money on it all those bikes had a crack before the failure. (The guy 'bunny hopping' knew his frame was cracked was doing it to see what would happen. ) – mattnz Dec 30 '17 at 8:17
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    It is very rare for a bike frame to break -- almost unheard of unless the frame is subjected to extreme abuse or is badly rusted. Steel frames are virtually indestructible, and alloy and fiber frames will generally give some sort of warning well before they fail catastrophically. – Daniel R Hicks Dec 30 '17 at 23:30
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No, they are not, if used in a way they are designed to and regularly checked for health.

I think that a proper answer to your question should include statistical information on what percentage of bicycle frames (btw, why only frames? wheels, handlebars etc. break too) break over the time. The reason of a breakage, such as crash or manufacturing defect, should also be taken into consideration. However, I do not possess such information. So instead I want to warn you against being affected by the survival bias effect by only looking at "bad" examples. I want to comment on several points in regard to the video above, or any other bike crash footage.

  1. We do not know how often and how hard these bicycles were crashed before they finally gave in. Damage, especially in carbon parts, is not easy to see without special equipment.

  2. Quite a few crashes in the video were caused by front wheel detachment. That's not frame but fork issue or rather user installation error.

  3. A couple of episodes demonstrate just direct crashes. Nothing is guaranteed not to break after that.

  4. I am not sure that all of these bikes were used in their intended discipline. I've had bad experience riding an XC hardtail on an DH course.

The good thing is, even after all these crashes most of the riders were able to walk away from them more or less fine. That stresses proper use of personal protection.

P.S. Every bicycle user manual that I've read (and I am one of those weird people who actually read manuals to things) states that bicycling is inherently dangerous activity. Not just MTB but any cycling. So, wear protection appropriate to your discipline, know your skills and improve them, regularly take care of your bike, and have fun!

  • In my opinion, road cycling is way more dangerous than MTB. Riding 70 km/hr on 1-2 cm contact points without any protective gear (besides helmet) and rim brakes... I'd take 2 meter drop or steep line on a full suspension with beefy tires any day! – J-unior Dec 30 '17 at 12:37
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    70kmph? I think that is a typo. Most road cyclists do not go faster than 20kmph, and those who do arrived soaked in sweat and need a shower before starting at work. – Hennes Dec 30 '17 at 15:10
  • @Hennes one difference though is that things going 70kph can hit you while road biking; MTB not so much. To be fair, though you can fall down a ravine or slam into a tree or rock during MTB but usually can't when road biking... – errantlinguist Dec 30 '17 at 18:46
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    Maintaining 70 km/h on level ground for 200 meters will win you world championships. – ojs Dec 31 '17 at 12:56
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    @Hennes I think there might be a misunderstanding. In English language road bike often means what you may consider as 'Racefiets' and not just any bike that goes on roads (eg an 'Omafiets'). – gschenk Dec 31 '17 at 18:45
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Generally a name brand bike frame (not a big box store bike) ridden within its design limits won't fail. Most of the videos show bikes being ridden beyond what they where designed for. The image in your link shows someone going off a 5 foot ramp on a 30 year old rigid framed "mountain bike". If that bike were made today it would be classified as a road hybrid. Most of the major brands have 4 or 5 types of mountain bikes. They vary by how aggressively they can be ridden or the terrain they can handle. If you ride a cross-country bike on a downhill course you are likely to see component failure. This not to say that even with the best components a serious crash won't break things. It is less likely with the appropriate equipment.

  • However there's no guarantee with carbon re: named or not, almost no one does ultrasound inspections of new frames/wheels and china carbon can be just as good if not better in terms of construction quality (and most carbon is made there anyway) e.g. Check out voids in Enve vs Cheap china wheels here youtube.com/watch?v=A8fsKeQwplg NOTE: The layup WILL however influence the characteristics of carbon massively, but it's not to say you always get what you pay for either in layup or QC, e.g. I'd expect full ultrasound void detection + rejection on Enve's at their price point. – Purr Dec 30 '17 at 3:47
  • So it looks like bikes aren't invincible, and I will have to look where I land my front wheel! thanks, if only I could accept all of your answers here :) – Nick Dec 30 '17 at 9:41
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Watch the video carefully. Many of those "bike failures" are a direct result of over stress on the frame compounded with user error. Very few of those are professional riders, most are amateurs with (presumably) little knowledge of proper maintenance.

A few examples:

  • At ~ 1:00 in the video - Working on (I think) a bunny hop, but basically just slamming up and down on the front tire/frame assembly.
  • 1:26 - Misses the landing, with way too much front weight on a high drop.
  • 1:40 - Again misses the landing area, with most of the impact being taken by the frame rather than shocks.
  • 2:20 - Runs into a tree at speed.

So rather than blame the bike, realize that it is most likely going to be user error or a stress beyond what was intended by the manufacturer.

Although, I would also make sure that while it looks cool, you need to realize that even the amateurs in the video spend hours practicing, and working their way up from basic trails/tricks to the stuff you see in the video. Along the way, you are definitely going to break a frame or two. It's the nature of the beast.

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    Yep, slamming into an immovable mass at speed, be it a building, tree or front face of a landing ramp is going to break a bike. Interestingly it's frames and forks that catastrophically break, not wheels. – Argenti Apparatus Dec 29 '17 at 17:18
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    @ArgentiApparatus - That's due to how the stress is transferred. Generally a wheel will have a wider, more dispersed impact area that gets transferred/concentrated up through the forks/triangle. The triangle lattice structure of the wheel is really quite strong in the vertical plane. However, if you land sideways on the wheel or impact the wheel/rim on a concentrated manner (Such as the edge of a rock), you stand a much greater chance of tacoing the wheel. It's all about stress dispersal. – JohnP Dec 29 '17 at 17:21
  • I was shocked at the one who's fork was torn out of the headset. That was a surprising experience. – Wayne Werner Dec 29 '17 at 18:59
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    FWIW, that doesn't look like breaking "easily" to me. There are some pretty serious forces involved in most of those examples. – Jörg W Mittag Dec 29 '17 at 21:51
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There are many scenes in that video of bikes being ridden well beyond their intended use, and consequently failing.

There are some scenes where a bike fails despite not being abused. That does happen occasionally. What you are not seeing is all the millions of times bikes did not fail.

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I would suggest that the range of conditions you can encounter on a mountain bike are wider than most other bicycles. That makes it easier to break a mountain bike because you hit something unexpected. I'm a roadie. Our bikes are built much lighter and you can ruin one (especially the really light ones) hitting a pothole. For us, that is outside the expected use. You can ride a mountain bike in reasonable terrain with good assurance it will survive. How do you assure that the terrain is reasonable? It's hard. You might ride a reasonable trail but miss a curve and hit a tree. As you ride you will get a better feel for the risks. You need to decide if they are reasonable for you. You don't have cars to worry about. Ride with others, learn from them, and have fun.

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No they do not break easy these breakages are due to extreme stunts being performed on a bike that is not intended for these stunts

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