Carrying a lock and chain
 

Increasingly locks and chains have to be bigger and heavier to be a deterrent. What ways have you found to carry yours by motorcycle, to keep the weight low and not scratch the paintwork and not take up space where I would otherwise put luggage (like on the pillion seat)?

I prefer a steel cable lock rather than a chain as I have found them easier to strap on, I have lost a chain after it came loose and fell off somewhere, I usually strap them on the passenger seat or if I have a passenger on top of whatever is on the rack.
I now question the value of the heaviest locks as with a battery powered disc cutter they are as easily cut as lighter ones but some insurance policies require them to maintain theft coverage.

The preventative to having a chain fall off and get lost seems relatively obvious: secure it properly, just as you would a duffle bag containing your underwear and socks.

I'd have to wonder about whether a heavier chain or lock is "as easily cut" as a lighter one. Taken to extremes, that would mean that a hardened 14mm chain could be cut as easily as the light-duty, mild steel chain you last used to secure your bicycle in elementary school. This fails the common sense test. Same goes for the 18mm shackle on the u-lock I currently use to secure my favorite mountain bike--which furthermore locks at both ends, so that it must be cut twice before it will release its equally-robust chain.

That doesn't mean your average London thief won't make quick work of either; I can't claim to know what works against a determined, professional thief. But there are degrees of risk in thievery as there are in riding practices. You probably wouldn't park your bike unsecured and unattended down a dark alleyway just because it might also get stolen when parked under a street lamp outside the police station.

In response to the OP, when I'm carrying lock and chain I put them low in my luggage, which is usually a hard case on the back. This requires digging through everything else to pull them out, an undeniable annoyance, but I've found it preferable to putting all that dense weight up high. When I'm not carrying a lot of baggage (therefore without cases or panniers) or feel extra lazy I drape it over the very back of the seat, bungied securely and locked to my pannier rack. Padded with whatever's handy it doesn't draw complaints from pillions; nor does it interfere with any extraneous baggage I want to carry there.

I carry a disc lock and possibly a cable lock if I'm feeling particularly paranoid, and carry them forward and low - in front of my knees essentially in whatever I have there for whichever bike.
Main theft deterrent - a good cover for the bike. That slows them down, makes it obvious, and then they hit a lock...

Finally, a truly determined thief will have three friends who can help lift it up and throw it in the back of a van. Or like the guys that went through a garage roof to hoist bikes out. You can't block every theft, only do what's reasonable.

Moto security is more than a big lock and heavy chain: I bring a cable lock but consider it a deterrent to the "honest thief." Secure the cable to the moto and to something solid. Don't ride a moto that is a target. Don't ride an expensive moto that you cannot afford to lose. Park in secure locations - inside a motel, in secure parking, etc. During short stops, park where you can see your moto. Pay or ask someone to watch your moto. Be aware of what security local moto riders are taking.

I carry my cable on a hold down strap on my luggage.

Disc lock
 

Disc lock is enough for me.
It stops anyone without tool to role away with the bike.
As stated, you cant stop dedicated professionals.

I often camp and sleep next to my bike.
Or use hotel that can provide secure parking.
I do not have bikes that stand out.
So...actually, the disc lock is seldom used.

I know one person that where travelling 5 month in South America. On a TSV 160cc. That bike was just one of hundred othars similar,

About 10 years ago, in a picturesque town in the home counties, a friend had his bike, with a disk lock on it, lifted into the back of a van in the middle of the day. It wasn't a particularly expensive bike, but it was a sought after model. After that I got big heavy chains and all my bikes were secured to solid objects (often my other half's bike, but I put an anchor point on the wall next to my parking spot too).

When I first moved to Spain people who saw me and my other half chaining up our bikes thought we were nuts. A disk lock and maybe a cable around a lamppost is plenty, if they can get through that then a larger chain isn't going to make a big difference ... as mentioned above, a cover is a massive deterrent too. Almost as much as having a crappy bike that's covered in dents and has been painted with a brush.

I have many friends who are urban bikers so I've heard the stories and seen the videos. The usual scene is 3 or 4 feral crotch goblins in hoodies turn up on scooters. One uses a battery powered angle grinder to cut off any chains or locks while the others brandish hammers or machetes to threaten anyone who thinks of intervening. Then they force the ignition lock and either ride away or push the bike away with one of the scooters. You'll be lucky if the cops take any notice and CCTV is useless as they cover their faces and use cloned or no numberplates.

You can cut almost any chain in seconds with normal bolt cutters (check out Captain Cropper on YouTube). To defeat even this simple tool you have to go to a massive 14mm through hardened chain which is way too heavy to carry around. Angle grinder much the same but can also be used to cut disc locks.

Given that passive theft protection is of limited value I try to aim for layers of protection and taking time, which is one thing they don't have much of. Alarmed disc lock to draw attention and cable lock round a solid object. Not much protection itself but just makes any theft attempt take more time - and they don't take up much weight or bulk to carry. And obviously, park somewhere secure whenever possible. Theft in big cities is a problem in nearly every country, rural areas generally much safer.

I've just invested in a Lite-lok D-lock.

https://www.litelok.com/


Grinder proof. It will secure a wheel to a post or work as a stand along wheel lock. They also do the band locks.

For general travel, the hollow or flat band locks are best.

No one wants a 16mm chain rattling around on their bike. Too heavy. Too noisy etc.