SFPD, Google Hosting Class on How to Improperly Lock Up Your Bike

Let us be totally clear here: this post isn't intended to rag on either organization for bicycle locking ignorance.  One organization is a government service tasked with crime prevention and security, the other parses vast amounts of information to provide us with the best resources available on any given subject, so it makes total sense that they'd be blanketing San Francisco with posters incorrectly telling people how to properly lock their bicycles.  I mean, neither is a bike company, so how would they know?

Therefore, in the interest in preventing anyone who may have seen this from being duped into this subpar locking strategy, we'd like to remind everyone how to actually lock their bike (via Sheldon Brown):

People tend to buy the big clunky U-locks because they don't know how to use them properly. A U-lock should go around the rear rim and tire, somewhere inside the rear triangle of the frame. There is no need to loop it around the seat tube as well, because the wheel cannot be pulled through the rear triangle.

Some will object that felons might cut the rear rim and tire to remove the lock. Believe me, this just doesn't happen in the real world. It is indeed possible to cut the rim with a hacksaw, working from the outside to the inside, but first, the tire must be removed or cut through. It would be a lot of work to steal a frame without a usable rear wheel, the most expensive part of a bike, after the frame.

The main reason SFPD/Google's suggested strategy doesn't work is the same reason cable locks just plain don't secure bikes: every thief has a pair of cutters that make quick work of the cable. If you use their locking suggestion, not only are you carrying around a relatively useless, bulky cable, you're likely to find both your wheels stolen, as opposed to just your front wheel.

Google it if you don't believe me.

Update: Matt Friedman of SFPD tells us the SF Bike Coalition is behind the poster and locking recommendation. Yikes.

Comments (38)

While we do believe you, we have seen on several occasions over 12 yrs that bike thief’s will indeed cut thru the back rim with hacksaw or some other device. I dont lock my bike up,but if i did its just better to get rid of quick release and get locking kind. ALWAYS u lock ur frame. Way easier to get new wheel set then new frame in most cases.(Unless ur bike is like the one in the picture)

I think the point is that sawing through a rim is more work than cutting a cable. If you lock up like the poster says then all they have to do is snip the cable and they have both your wheels. If you put the lock through the rear wheel along with the frame then they only get the front wheel with a cut cable.

What is probably more effective though is making sure you are always parked near a nicer bike with a poorer locking job.

Full disclosure: I work for Google, but not on anything related to this. Yes, I’ve seen the poster and have rolled my eyes at the diagram.

I find it amusing that you skip over the other sponsors who should also know better about how to lock up a bike, e.g. Bicycle Coalition, Valencia Cyclery. “I mean, neither is a bike company, so how would they know?” Yes, but there are two organizations also displayed jsut as prominently on that poster that are bike companies or coalitions who should know.

Totally, and I was considering mentioning it, but ultimately 1) Google is hosting it and heavily promoting it on Twitter and 2) SFPD is also heavily promoting and managing the event, whereas SFBC + Valencia Cyclery + Sports Basement hasn’t really taken a lot of ownership over it (I suspect it’s largely product/financial sponsorship and they have very little to do with the admin of the event).

Kevin The bike coalition designed the poster and from what I understand their can be several locking techniques that are effective and the poster demonstrates one of them. The sports basement and rei have all heavily promoted it. Google sf and the SFPD use social media a lot more and since u follow us I tweet about it to inform the community on a daily basis. Valencia cyclery donated labor and product. Google sf donated catering and space. Everybody is doing something to contribute. If you disagree with the locking technique then contact the coalition and voice your opinion. Valencia cyclery will be teaching a different technique at the workshop. This is a positive community event that brings together groups who all have an interest in stopping bike theft. We hope to see you at the workshop where you can voice your opinions in a discussion led by members of the bike coalition

As an odee sckool bike mechanic I have great respect for Sheldon Brown. I don’t think this is quite right though. With quick release hubs I always remove the front wheel and lock it to the seat tube, the rear wheel, and the bike rack. This assumes a normal size U lock. That kind of U lock is vulnerable to a lever or jack attack. We would therefore add plumbing fittings to it for added strength. I now think the best way is to have two small size U locks, one for the front and one for the back. The front one goes around the down tube and the wheel, the rear one can be done in the Brown manner. I also think there are some high grade chains and locks that look pretty promising but they require a different method altogether.

Indeed, and if you want the ultimate in security you can also just weld your bike to the pole?

I think the standard Brown method is a good compromise as a single lock/cable solution.

Yeah the key is to balance maximize convenience (for you) and inconvenience (for the thief), not to come up with an imaginary theft-proof arrangement that requires two u-locks, a chain, and a rivet gun.

Sheldon Brown discusses this at length. It’s crazy to have to dismantle your bicycle to lock it securely. Your strategy also requires using quick release skewers (which invite theft). It also means releasing and readjusting your brakes every time your park your bike.

The best strategy is to use Sheldon Brown’s method to secure rear wheel and frame, and a separate cable lock to secure the front wheel only. Typically, thieves are equipped to defeat only one lock type - either U-lock or cable, but not both. You may be able to secure the saddle with a bolt rather than a quick release. A ball bearing glued into the hex head will deter most thieves.

Rumor has it that thieves along Market have taken to cutting the frame tubes of bikes locked this way. And yes, cutting through a rim is extremely difficult.

Why would they do that? Doesn’t that destroy the bicycle?

My friend had someone cut right thru their frame. Another guy I read about on a bike email list caught a thief hacksawing the frame to remove the lock on Market St. It’s definitely a thing.

The reason is simple: sawing through a thin-tubed aluminum bike frame is far easier than cutting a ulock. If you hacksawed anything before, you’d get it… cutting a bike frame is as close to warm butter as it gets.

The thieves throw out the frame and sell the wheels, saddle, bars, brakes, pedals etc. at flee-markets and/or online. It makes sense because entire bikes are much more identifiable than just some parts online and therefore carry much more risk than flipping the wheelset (itself very valuable) and some random parts. Hacksaws are a lot smaller tools than bolt cutters or a jack/crow bar, so the crime itself is far more visible.

Also, this is another reason why Sheldon’s strat works better. Cutting thru a rim and tire is more of a pain in the ass than a downtube. Better yet, lock thru your rear rim and chainstays/rear triangle… most thieves won’t bother with all that hassle.

Realy hope SFBC wasn’t responsible for this as the officer suggested, because this is would be another blemish on a org that’s been fucking up a lot lately.

Sorry, that was supposed to say that the crime of hacksawing a bike is far LESS visible than bolt cutter/jack attacks…

I see a need for some sort of POP up on friday-saturday nights at the least. sanctioned city bike corrals,kinda like when the SFBC does valet for events. people could even pay a monthly rent on safe, controlled,valet parking for bikes in mission.use empty storefronts as the locations.

Please come to the workshop and voice your valuable insight its very much appreciated and welcomed. I would like to get as much information as possible from experts to put together a better enforcement plan and it starts with valuable input from people like yourself, the coalition sf safe, folks from Valencia cyclery and everyday riders. Please consider coming. Thank You!

This comment is spot on. I wrenched at three different shops over the course of 5 years and can assure you it takes someone less than a minute to saw through an aluminum downtube with a fresh blade. Most major bicycle manufacturers require shops taking in warranty bikes to cut out the bottom bracket of a defective bike as proof of its destruction/ensure no one will fish it out of a dumpster and continue to ride it, so anyone who has spent any time around a shop knows better than to lock the frame exclusively because they’ve seen just how easy it is.

Ultimately, wheels are built up to take much more abuse than a frame itself, so they are double walled and have more material to cut through (and are significantly more difficult to fit a full-sized hacksaw into when installed on a bike).

But assuming the thief doesn’t saw the frame to steal the bike, the other failure point with the frame locking suggestion is that it’s a poor strategy if someone only has their ulock on them (an extremely common situation, for whatever reason the person may have), as it leaves both wheels completely insecure. The rear wheel is generally the second most valuable part on a bike, so any strategy should emphasize securing your rear wheel (and, therefore, your frame) with your primary lock. The front wheel security offered by a secondary lock is just gravy, but shouldn’t be relied upon.

Also a bike that has either it’s seat or top tube cut is just some duct tape away from being able to ride the thing away for a short distance. Good luck getting anywhere with the back rim cut.

I generally go the Sheldon way and in my years of wrenching never saw a bike with a cut rear wheel, but if there isn’t an easy locking point for that method, method two is to lock at the head tube as it’s a bitch to cut through the head tube and steering tube. (I don’t have quick releases on my wheels)

It destroys the frame, but the remaining parts are still worth something. Since bike theft is basically a zero-risk crime there is no reason for the thief to need any kind of minimum payoff to make it worth his time. And from what everyone else has said, it is probably the easiest way to separate a bike from a rack anyway.

A couple of years ago someone cut down a tree on California Avenue in Palo Alto to steal a bicycle.

The joke is on them – the city recently cut down the rest of the trees on California Ave.

This post is pretty insufferable. That is a fine way to lock a bike , and less cumbersome then the rear triangle, while also protecting the front wheel.

Enjoy buying a new wheel set!

Even putting the lock through the front tire is better than the method on the poster, and is negligibly harder than what is shown. Threading a lock around the rear tire, frame, and rack can be hard, particularly if you are locking to something that already has another bike on the other side.

I’m surprised no one has mentioned the pinhead wheel locks http://www.pinheadcomponents.com/ They’re great, and you don’t need to carry around extra cables/locks for the wheels. A set of these plus a small Ulock for the frame and you’re set. (I don’t work for the company, or anything like that).

However, nothing beats the tried and true strategy of simply not leaving your bike outside. Of course, that’s not always an option.

Those are interesting. Pitlock also makes similar systems but I’ve never come across any that are recommended for horizontal dropouts.

Which is also easily defeated. Don’t use locks in place of a portable welding rig.

pinhead changed their design this year. they added an extra washer per skewer. it has a tab on it that slides into the dropout and has two more tabs protruding away from the frame. with that new washer the gator grip doesn’t work. you can still go at with a hammer and punch but it can be difficult.

I’ll immediately grab your rss as I can not in finding your e-mail subscription link or e-newsletter service. Do you’ve any?
Please let me recognize so that I may subscribe.

All of this debate makes me wish I were inside the event listening instead of valeting the bikes for the event. But when you do come, make sure to say hi to your human bike locks watching over your rides! :-)

if you have a few hundred dollars to replace the nuts and bolts, there’s this:


That shit is bling yeeee-0hhh.

Lovely holiday gift.

This is terrible advice. If the lock only goes through the rim and the bike is yanked on or bumped into, the rim can be easily bent.

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