Breaking a U-lock
 

My bike was locked to a pole.

I managed to lose the keys.

It's an On-Guard lock.

How to best break this? Maybe a locksmith could help? Saw it open? I put on a second lock which is a combination lock so that should help...

U-locks can be broken by various means, but I don't think a public forum is the place to discuss how. If you want feel free to PM me and I'll give you a few ideas. BTW- if it isn't far from a bike shop where you have a relationship, most dealers are familiar with a variety of methods, and might break it for you at a nominal cost.

hydraulic cutter or angle grinder.
just watch, as you make a lot of noise, but no one will bother to call the police on you.

http://www.youtube.com/watch?v=JzNaD_rEUr4

If this girl can do it, you can too.:crash:

any battery powered reciprocating saw should do the trick:

http://img.directindustry.com/images...saws-59733.jpg

case hardened steel would not cut with a toothed hacksaw blade.
a carbide grit blade, maybe..

My kind of girl! :)

An angle grinder can eventually get through almost anything.It took the young woman just 2 minutes to get thru about 1/2" diameter of tough steel.
The plug powered ones will work much faster-get someone with a generator and a pickup.My 4.5" one takes 570 watts-about 5amps 110 volts.

The best way to break U locks is to drill out the keyhole with a portable drill use a burr bit if you can it is less likely to hurt you if you slip. I'm going to suggest you break down and call a locksmith.

An abrasive cut-off wheel, like an angle grinder or even one in a Dremmel tool will cut it easily. I used a battery powered Dremmel to cut through the shank of 3/8" drill bit in about 30 sec. The shackle of a lock was quicker.

Probably not helpful in this case, but On Guard locks come with a tag that has a registration number on it. If you have that, I believe they will send you a new key.

Here at the university, we occasionally have to cut 'em when the kiddies loose their keys. Our facilities guys always use a portable angle grinder.
I can testify that you can do it with a hacksaw and a carbide blade... About 20 minutes of steady work.
As noted, might be easier to get a key if you have the serial number...
Make sure you can prove it's your bike should someone call the police.

This isn't a secret. Just get a scissor jack from a car and jack it open. A small hydraulic bottle jack works nicely as well.

http://www.bikeforums.net/archive/in.../t-605009.html

Yeah. Remove it from the pole first so there's room for the jack.


Oh wait...

For non forceful methods, search youtube for 'opening U lock'
popular a few years ago.

I lost the little number.

I'm going to try to find a hand saw of some sort. I have proof of ownership of the bike and I can see myself sawing for half an hour. Suggestions?

angle grinder.. takes about 15 seconds. Had to cut a lock off mine when I lost the key

problem is electricity. Also, if I do get an angle grinder...how to safely cut it?

Did you call a locksmith and get a quote? It may be cheaper then getting equipment and worth it compared to sawing for a 1/2 hour straight with a hacksaw.

You will have to use a carbide or diamond edged saw blade. A regular steel hacksaw blade won't (wait for it...) hack it.

An angle grinder or Dremel with an abrasive cut-off wheel will go through hardened steel relatively easily and there are battery powered versions of both.

locksmith would be approx $150

gah, fundamental problem is the bike key. This is an old bike lock. Ironically, my newer ulock had the key get stuck -- I also have the spares for that one readily available, but not for this older one!

Solution would be a good combination U-lock. Suggestions?

Do you have a buddy with a pickup truck-maybe someone who owns a generator? Haul a generator there and use an angle grinder.
You can get an angle grinder from Harbor Freight for $25 or less.
A Battery powered angle grinder will work ok-take maybe 5 minutes instead of the 2 minutes the woman in the video took.
A Dremel tool will take a long time and several tiny cut off wheels.
A hacksaw will take a long time- maybe 1/2 hour-.It will be tough to get it to initially "bite into" that tough steel.It will want to slide from side to side.