How To Fix A Bent Rear Mech | Mountain Bike Trailside Repair

At some point during your mountain biking career you'll have the misfortune of damaging your rear mech. You might smash it on a rock, drag it on the edge of a rut, or twist it in a crash. Luckily, Doddy has some tips on how to straighten a bent mech, get your gears working again, and avoid a long walk home. Here's how...

Follow us on Instagram or Facebook! @gmbntech

Do you want to see more trailside repair videos?

Watch more on GMBN Tech...

🎵 Music - licensed by Epidemic Sound
Turning Tables - Dusty Decks

#GMBNTech #GMBN #MountainBiking #MountainBike #MTB #BikeLife #Cycling

Brought to you by the Global Mountain Bike Network (GMBN), GMBN Tech delves deeper into the bikes, kit and technology that powers your rides!

Our mission is to help you discover, dial-in, and get the best from the latest cutting edge bikes and technology available.

If it’s off-road tech you’re after, look no further! The weekly GMBN Tech Show showcases the latest and biggest tech stories, with more besides.

Fancy some factory tours and first looks to keep you informed of how the latest tech has arrived, as well as what they do on the trail? You’ve got it. Want some in-depth maintenance videos give you the knowledge to set up, look after and upgrade what you’ve got? Yep, we’ve got them, too. Lots of ‘em. In fact, our presenting team consists of bike industry professionals with decades of experience of wrenching, writing, and working at the cutting edge of mountain biking so we can keep you informed, entertained and engaged with all the tech that drives mountain bikes forwards!

Thanks to our sponsors:

[evilmrx]

Going to say, with respect to "single use" master links... have never run into an issue re-using them--HARD. They don't blow apart like paper in the wind. We all carry a spare for many reasons. I don't think we need to call them "single use" anymore. I get it if you f*ck one up... but they're not generally that delicate. Love the show lads, keep it up!

[runevw]

When GMBN, GMBN tech, GCN, GCN Tech upload at the same time.

[wordreet]

LoL! For me, it often involved kicking and shouting! The shouting does nothing by the way.

[charlieine]

I think this is a very useful aspect of GMBN Tech. Field tech. I enjoy all the shop videos but segments like this are extra helpful because they deal with situations that happen out of the shop and have to be dealt with on the trail. Great! Thanks Doddy

[georgelives]

Nice instructive video 👍🏻
In reference to the missing cable end cap, i always degrease the end of my cables then apply industrial grade super glue. Only takes a couple of drops and haven't had a cable fray yet. Enables me to remove the derailleur multiple times for cleaning etc without having to replace the cable.

[TimMillernapavalleyfilmworks]

I've been reusing links for years 👍🍹

[canadianboyee]

I know you're not supposed to reuse quick links, but I take my chain off a lot to give it a deep clean in kerosene and usually reuse them a couple times, never had a problem in years( knock on wood haha)

[mattgies]

To remove the chain from the derailleur, you don't need to open the chain. Just remove the lower derailleur pulley, loosen the screw for the upper pulley, and pivot the inner cage plate around the outer one to free the chain.

[codyclark]

i think your my favorite tech always simple and dang did this just help me loads!!, new hanger but still couldnt get lined up I thought the mech looked off, grabbed it like you showed gave it a bit of a tweak and boom chain noise gone all gears accessed ... was loosing my mind lol...good on ya Mate!

[CCCSchneider-tclx]

Excellent video. very good instruction and visuals.

[Bianchiboy]

You could do to actually get off the trail Doddy ...

[nicolaslaurent]

Hey Doddy, didn't you mount your master link the wrong way ??? I've been told to mount mine (SRAM 10 speeds link) with the arrow in the rotating direction (arrow facing backward when on the bottom )... Am I wrong there ?

[stigsy]

First thing would be to get off the trail and do the repair there...
I never understood why people drink, talk, repair etc directly on the trail.
...but thanks for the repair idea.

[dundundata]

I've broken 2 derailleur hangers in short order and so didn't have a spare. Had to cut the chain short and install another link turning the bike into a "single speed". Got me home.

[travelblogger]

And that #Shimano provided to Doddy the new rear mech 🙂

[willbennett]

I like what you’ve done with your pedals doddy might have to try that with my mallet Dhs

[dirkg.]

Since I run 12 gears an alignment gauge was best investion ever....👍👍👍

[CyclingLifePT]

What i've learned from this: always carry a spare derraileur with you, or, remove the derraileur completely and just setup the gears in a fixed position that could allow you to get home.

[jpg]

Had a few incidents where needed to turn my bike into a single speed to get home

[JoeBob]

I'm by no means an expert, in fact I'm so much of a novice that I don't know how to break a chain, but when messing with my bike yesterday I removed the derailleur by disassembling it and removing the pulleys, instead of breaking the chain.
It's a lot more fiddly to get it back together, but definitely an option if you don't want to break the chain.