Cross posted (by me in response to the same question, and some other questions....):

"


Originally Posted by skellener
"Well, if that is the case, the bike is gone no matter what lock you use. I think the idea is to keep the "not so serious" bike thieves from getting it.

Still wondering if anyone has info on combination vs. key type locks?"


Originally Posted by NEXUS
"I have only and will only use one kind of lock and that is the Kryptonite Kryptolok Combo U:



And the reason is I hate carrying around keys that can get lost. I even have an electric combo lock for my house front door. Life is so much easier this way. A few months ago my best friend who now lives out of state had a unexpected business meeting here in town and wanted to spend some time with us afterwords. We were actually out of town so I gave him the combination to get in the house and the combination to the U-lock if he wanted to go for a bike ride. Saved him hotel and car rental!

If you live in a bad area then this lock probably wouldn't be good enough for you since it's not that thick. You would probably want to go with the OnGuard 5012C Bulldog DT Combination U-Lock & Cable"



" Convenience=a compromise in security.
Usually.
If one knows how, it takes a matter of seconds to turn the right combination and open that lock. And, unfortunately, to people passing by it just looks like you are fumbling with the combo on your lock.
Handy and easy if you live in a small town. Easily stolen if you are in a larger city.

P.S. I don't want to scare you, but if you spent less than $600 on your keypad entry lock on your house, you should replace it with a better one, or go back to a good ol' fashioned heavy duty deadbolt.

I deal with at least two people who have had their homes broken into each day (average).
Take this with a grain of salt. If you live in a nice, small town with a low crime rate, obviously don't worry.............
....but if you don't.
How much is your peace of mind/safety/big screen/bike worth to you?"



Originally Posted by NEXUS
"The house lock wasn't that expensive but it is a deadbolt lock. If some guy really wanted to get it her would just go through a window.

So how does a person figure out the combo to a lock in seconds?

And yeah, I live in a really safe town with almost 0 crime."


" I am glad that you live in low crime area. I do miss those days.... Hey, whatever works for you. I just hate to see people that think their homes are secure after buying locks from home depot and the like.

Without becoming too technical and/or giving info on a technique, there are 'gates', that you can actually see or feel as you spin the dials. Depending on the particular lock you have in front of you (make,model) you have to know how to 'transfer' them to the actual combo.
So, for a hypothetical example, I see/feel a gate at #4 as I spin the first dial. Knowing that with this particular lock they offset the 'gates' 2 numbers, I dial back 2 numbers.
Next chamber.......etc.....
There is some knowledge, skill, and good eyes involved, but with practice anyone can learn.

There are actually races at ALOA (associated locksmiths of america) conventions involving these, and many other opening techniques.
They even give you prizes!
I know it's annoying to carry keys, but to all out there who live in an area where your bike even MIGHT be stolen, please use a good solid, keyed lock. "

Edit: I will add that most of the newer U locks are using "disc tumbler" cylinder systems. While these are very good, time tested cylinders, they do have their problems.
Sometimes, because there is no spring tension on the disks, they get out of alignment. You have surely tried to put your key in and had it not go all the way in, causing you to have to fumble with it to get it to turn.
When this happens, while you insert the key, jiggle and turn left repeatedly as you push it in until it gets to the bottom.
Annoying.
Disk tumblers can be defeated, if you know how. But they ARE much better than standard pin tumbler padlocks, or tubular key cylinders.

Tubular cylinders are OUT because they can be opened with a bic pen. While this is true, it got all way blown out of proportion. It is still a difficult thing to do. Go ahead. Try it.
Still, don't buy a tubular (looks like a round hole on the keyed part) keyed bike lock.

All that said, most theives don't pick locks. They break them. You can't do much against an angle grinder. With the right cutting wheel, they can cut through any material that I can think of. Including a highly tensioned rim. I have done this as a test. It took about 20 seconds.
So, weigh convenience, cost, and weight. Buy the best lock that you can. Use it every time. And forget about it.



As to ON GUARD locks vs. KRYPTONITE.
I have seen more lock failures with the on guard brand than the kryptonite. In fact, I have never had a customer bring in a kryptonite lock that was broken in any way, only to have them removed from bikes, or keys made.
They function almost identically, and can be defeated in exactly the same ways. So neither is more secure than the other in my opinion. However, the kryptonite brand locks DO SEEM to be built quite a bit more robustly, with tighter tolerances and cleaner machining. I own two of them.

So, for lasting, quality operation, I go for the kryptonite over on guard. It is best, IMO, to invest a little more cash into your locking system.


You can't prevent someone from taking a cordless angle grinder to your locks. This is what we usually do to remove locks legitimately for customers. Your toughest lock or chain will be defeated in 3-5 minutes, tops. You can, however, persuade the opportunist (most common theft) by using a high quality locking system to deter them onto the next (easier) bike to steal."

Originally Posted by SlimAgainSoon
"Hey, Mr. Locksmith -- what about graphite?

I always thought that was the thing to use on locks."


"^
Powdered graphite (extremely fine) was considered the best lubricant for cylinder plugs (only) (the part that the key actually goes into) for many, many years. And it works really well......

...Until any kind of liquid, dirt, gunk, particulate gets in there. Bike locks get A LOT of foreign material into them. On interior door locks, where you won't see that happen, it works really well.
Once some foreign material gets into the cylinder, the graphite attaches to it and clumps up. It happens all the time when some 'genious' maintenance man has a lock issue and thinks that WD40 is a magic cure all. That makes everything even worse and more sticky when it dries. This negates its effectiveness entirely.

Don't use graphite or WD40 on your bike lock. "


Maybe too much information for your particular question, but I thought I'd just throw it out there for any new readers who don't want to sift through all the pages.