If you’re the type of cyclist who counts their yearly mileage figures in the thousands, you’ve probably experienced a gear hanger failure at one time or another. To anyone that is unaware of which part we refer to when we say gear hangers, let us explain.
As anyone who has ever experienced a gear hanger failure will tell you, it’s pretty inconvenient. Having a gear hanger break on you, mid-ride is normally terminal for the chances of that particular ride. It almost undoubtedly results in a phone call to order a taxi or beg a lift back home. But there are ways in which you can minimise the possibility of a failure and maximise the lifespan of the bikes gear hanger into the bargain.
How do gear hangers fit and what do they do?
This part is known by many names – gear hanger, mech hanger, or derailleur hanger. They are all one and the same and are used to attach the rear derailleur to the frame. It’s a sacrificial part that is designed to bend or break in the event of a crash or impact. Should such an impact occur, the hanger bends to prevent potentially catastrophic damage from occurring to either the frame or derailleur.
The gear hanger is bolted to the frame’s dropout at one end and the rear derailleur is attached at the other. It attaches to the frame by way of one, two, or in some cases three countersunk bolts. If you have ever searched for a gear hanger online, you will know there are literally hundreds of variants. Bikes from different genres will require a specific model of hanger that is specific to that particular frame. This can make finding the correct hanger a bit of a bind. Thankfully, here at Ribble, we’ve simplified this process by designing our range of frames to share the same hanger where possible. For instance, our entire SL carbon family of bikes all use the same hanger.
Here is a gear hanger in action – blink and you’ll miss it!
Why do they break and how to avoid it! (Overshifting)
So now we’ve explained what they are, let’s get down to the nitty-gritty of what causes most failures. You may recall us stating earlier that hangers are made from a soft metal that’s designed to break under extreme load? This may sound a bit strange, but the reason for this will become increasingly obvious. It’s to protect the more expensive parts of the bike, firstly the rear derailleur and then the frame.
These are, if you like, the ‘weakest link’ in a bike’s drivetrain. However, if it boils down to replacing a hanger that costs £20 or a derailleur in the region of £30-£300, it’s really a no brainer! Then there’s potentially the new cost of a new frame to factor in. It’s therefore clear to see why gear hangers are designed to work in the way that they do.
There are a few factors that may cause a hanger to fail, apart from the most obvious cause…a crash. The most common cause for new bikes is either damage sustained in transit or user error.
Damage in transit
Despite our packing teams best efforts, it is possible (though thankfully rare) that the bike can arrive with a slightly bent hanger. Therefore, we advise all customers to check the bike over upon delivery and pay particular attention to the gear hanger. The way to check for this is to look at the hanger itself and see if it bends towards the wheel slightly. The derailleur will also be slightly misaligned with the sprocket that the chain is currently sitting on.
User error as a term sounds a little harsh, maybe a better way of describing it would be ‘rookie error’.
If the bike arrives with a slightly bent hanger and no action is taken to rectify it, the gears will be out of alignment. If you then take it out for its maiden test ride the gears are liable to slip under load. The already stressed hanger could then fail with dramatic effect.
Being in the wrong gear combination – In cycling, there is something that should be avoided at all costs…. ‘cross chaining’. This occurs when the chain is in big/big or small/small (see image above) and the chain sits at an acute angle across the gears. In this position that chain is likely to chafe against the chainring, sprocket and front derailleur. This is to be avoided as much as possible as it will result in premature wear of the components.
Another issue that crops up from time to time is one that can be attributed to anybody – from beginners to seasoned cyclists. When climbing, you get to a point where you can barely spin the pedals and find you need to shift to an easier gear. By this point, you’ve left it too late and when you do eventually shift the gears let you know in no uncertain terms that you’ve erred. A horrendous crunch emits from the drivetrain as they protest at their mistreatment!
Other common factors that can cause a problem are.
- an incorrectly fitted or worn chain. An essential tool in any cyclists armoury is a chain checker.
- a chain that is too short for the chainset/cassette combination fitted.
- debris in the chain or derailleur.
- incorrectly set up gears.
How to prevent hanger failure, Do’s & Don’ts
Do keep your chain well maintained. Clean your chain regularly and apply lube once it’s dry. The same goes for your derailleur, cassette, and chainset. A clean drivetrain works more efficiently and will extend the lifespan of the components.
Do check your chain regularly for stiff or possible bent links.
Do ensure that after fitting any new parts to the drivetrain, the gears are set up correctly – reset and adjust if necessary.
Do make sure that you are in the right gear for starting off and climbing. Always start off in the small/inner ring at the front, and ensure you are in a suitable gear combination before the road ramps up on a steep climb.
Don’t lay your bike down or transport it derailleur side down. The most obvious example of this is when transporting it by car. The rear derailleur should always be facing upwards.
Don’t lean the bike precariously, whether this is up against a wall, other bikes etc. Ensure that it’s stable and unlikely to fall over, such a fall is highly likely to bend the hanger.
We hope you have found this guide helpful? The advice given goes some way to ensuring that your gear hanger lasts as long as you have the frame. And that you won’t have to try and limp home if one does snap on you!
Have an older model of Ribble frame and want to know what gear hanger you need? Find out what you need here.
For the correct gear hangers to fit the current range of Ribble frames click here.