Super Easy Bike Chain Lock





Introduction: Super Easy Bike Chain Lock

First off I go to art school in San Francisco.  The school provides shuttles that go to all the school buildings, but are quite slow, thus I ride my bike all the time.

Last semester I lent my bike out to my roommates friend for 2 days (I know, bad Idea).  He returned everything, but the ulock key, and mini pump.  Oh yeah I forgot to mention that he left the ulock locked on my bike frame.  Long story short, he never returned the stuff, so I began to look for a new lock.

I browsed online and read that chain locks provided some of the best security, but i found them to be quite spendy ($20-65, yes $20 is spendy, I'm in college :P).  So I sought out to make my own chain-lock for cheap!

This build is so easy it's pretty ridiculous and should cost you less than $12.  Let's get to it!

Step 1: Getting the Right Chain

 This part like the rest of the build is simple.  Go to the hardware store, buy the thickest chain you can (within reason).  You want a heavy duty thick chain for the obvious reason that they are hard to break.

I don't recall the exact specs of the chain I bought, but it was about $3 per foot.  I got 2 feet which Is enough to at least lock the frame to a post.  I think 3ft or 4ft would be ideal.  You can make it as long as you want within your budget, just keept in mind you have to lug it around.

On to step 2!

Step 2: The Lock

 This step is as easy as the last one, and like the last step it's all a matter of preference.

The Lock I am using now is just a hardened padlock I had lying around.

I prefer combo locks for bikes and lockers, because you don't have to fish around in your key ring for the right key.

It really is up to you.  Just remember to try to find a lock with about the same shackle thickness as the chain obviously.

A good heavy duty lock can start from around $4 to $15.  A good place to look is ebay, Amazon, and I bet craigslist wouldn't be bad either.

Step 3: Finishing Touches

Up to this point your done, but as you probably have guessed the chain might be hard on your bike frame.  Don't worry this is easy to fix.

At my School Apartment, right after I bought the chain, I found my reusable grocery bag that had ripped on a prior grocery bike run.  So, I cut up the bag and made it into a sleeve for the chain.

It's pretty easy I just cut the bag into a strip and wrapped it around the chain.  Then I used a rubberband at each end of the chain to stop the sleeve from sliding off.  After that If I were you I would use some gaffer's tape (you can use duct tape, but it ain't as good) and tape the sleeve.  You don't have to cover the entire thing in tape, I just taped mine up like a coil.

Step 4: Your Done Baby!

Congrats you have just made a super cheap n' easy chain lock.  Mine is a bit crude, but Ideally I would tape it again with gaffers tape and tape the ends of the sleeve and probably choose better colored rubberbands.

This has worked fantastic for me, and for coming to only $7.60 or so, You can't beat it.  Tough it may be more expensive for you depending on if you have to buy a padlock or not, but it still is cheaper than the brand name and works just as good.

Hope that helps you guys and saves you some cash too! 




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    17 Discussions

    Although a nice idea, using a regular chain for a bike lock is a terrible idea, for the reasons already mentioned in the comments. A regular chain is regular steel whereas a bike lock or chain is made of hardened steel. Hardened steel is processed steel which trades a bit of flexibility for hardness. Hardness is what you are looking for in terms of resistance to being cut.

    I know this is kind of an old 'ible, but still a great idea. Another way to cover the chain and protect your bike's finish is to repurpose an old innertube. Cut a section long enough to cover all but the ends of the chain and slide the chain into it. It's not pretty, but does the job and keeps an old innertube out of the landfill.

    Not my idea, I saw it somewhere else, but I have done it.

    NO they don't save you money dumbass!

    You should get tough security chain, not regular chain from a hardware store. It is much harder to cut. Both the chain and lock pictured here are pieces of crap.

    It is hard to find security chain as it is very tough to cut. If the store you buy your chain from can cut it without a oxyacetlyene torch then so can a thief!

    Consider buying this chain. It's a bit cheaper than kryptonite etc.

    Using a crappy lock is the definition of false economy.

    I can tell you from experience that it is a long sad walk home thinking over your foolishness when your bike is stolen due to an inadequate lock..

    Kryptonite locks cost the amount they do because they are made of hardened steel, and a lot of it. This is also true of cheap and expensive U locks. It all comes down to the rate of crime in your area. If you live in NYC or another larger city, that chain would be history by the time you walked in and out of the drugstore. If you live in a small town/rural area then this is fine.

    For a finishing touch, find an old mountain bike inner tube, cut to size and thread your chain through. It will look a bit better, protect the chain from the elements and not chip your paintwork!


    1 reply

    Even if you spend a hundred dollars on a kryptonite chain with a case hardened lock, it's still vastly cheaper than replacing a bicycle.

    When making your own look for case hardened chain. Not always easy to find but worth the laugh when you see minuscule tool marks on your chain and know some bike thief now owns dull bolt cutters.

    That's exactly what I did, some bro wrote me on here and I was like "that might just be crazy enough to work!" and It did. Kinda hard to unscrew at times tho.

    Good information but as someone in the bicycle "anti-theft" community i can't recommend using a chain and a regular lock. U-Locks are safe and cheap. chain will be cut like butter by your experienced bike thief, especially in sf.

     I was wondering about a third type of lock.(An Idea that just came to me).
    With the ease of picking locks that use keys, and the ability to break combination locks. How about a combination lock but with the shape of a disc padlock? I will do some searches and try to find one if it exists. 

    I have some words of advice to people who actually think about buying the "classic combo locks", don't. As a college student myself, I have learned to appreciate the cheap things in life until, I realized not all cheap things are made equal. I brought a classic combo lock only to realize to late it was not as good as a master lock. With swift pulls on the classic combo lock it will open. Do it enough times it will break.

    The only combination locks I recommend are master locks, but even those have their faults. Military guy, and military boots can make the master lock break like the classic combo. Just my 2 cents, don't buy cheap locks.

    1 reply

     Yeah Heavy duty Locks are the way to go.  Cheap Locks aren't that great.  Bought some recently and they ended up sucking.

    This may or may not affect any of you but I have a comment on locks. I lockpick as a hobby so I have a good idea what a good lock is. Master locks wile hard to brake are increadibly easy to pick. I can pick one thats in good condision in about 15 secs. Most locks cheaper then a master is childs play to someone skilled in lockpick. I'm not shure of any brand name but all of the brass locks that I've tryed to pic end up takeing howers of work and any would be theaf would give up by then. Mind you Im talking about a standerd lock picking method and not bump keys, shives or any other method that makes most locks useless. Also, a good combo lock removes this factor compleatly. Just food for thought...

    1 reply

     Yeah I definitely Agree.  I went up going with a Master Sphereo Combo Lock.

    Yeah! This is my favorite type of lock. I used to make them all the time for friends and clients in Montreal where bike theft is common.

    These have three great advantages over U-locks and other locks. First they are flexible in that they can lock to a variety of things unlike U-locks that can't go around large poles or trees. Second, U-locks have some inherent vulnerabilities other than the lock mechanism, chain is stronger. Third, other locks are integrated so when the lock fails due to corrosion, the whole thing is useless; whereas a chain lock is modular, the chain will never  wear out, ever and you can replace the lock inexpensively. And as a bonus, you can make a chain lock for the same price or cheaper than any other bike lock.


    1 reply

     Woot indeed my good sir!  custom chain locks are the way to go, they save you so much money!