Cycling UK Forum

Hi all, I've just finished building a wheel around a dynamo hub which I was planning on attaching to the bike via a pitlock skewer. The plan was to mount the light to the fork crown just using the existing brake calliper bolt but now I've learnt the local low-lives are going around stealing dynamo lights mounted this way so I'm looking for some way to secure the light?
Does anyone know if any of the pitlock range are suitable for dual-pivot brakes with recessed brake calliper bolts? The picture for their V-brake bolt looks more like the traditional bolt-through variety. Pitlock makes sense because I only need one 'key' for everything but if not are there any other alternatives?

V-brake post bolts are M6 threaded, as are brake bolts.

One possible solution would be to use a rear caliper bolt at the front, and use a 'connector nut' inside the steerer to join the caliper bolt to a pitlock bolt on the back of the crown.

Another option is to rivet over a standard nutted fixing (so that you need a grinder to remove the nut, or

-you could use a shear-off security nut, or
- glue a ball-bearing into the allen key socket,

etc.

Of course you could always get a cheap non-scumbag-magnet light. Even if the bracket is secure for an expensive one, the light can come off the bracket or the bracket can be cut through....

cheers

...the other thought which strikes me is to engineer yoru front dynamo light in such a way that it can be taken off and placed in your pocket... Clearly the wires to the dynamo light would have to have some water-proof, push-pull fittings to make connection easier, and perhaps use different coloured wires if you weren't using the frame as an earth connector, and then perhaps a simple bolt and wing nut... or if your were using an actual bulb rather than a light emitting diode, you could modify a headlamp that features a quick release that used to be powered by batteries...

...of course the benefit of all the hard work in setting up a quick release front headlamp is that if you chose to use an expensive model, you could switch it between bikes! (providing, of course each bike was fitted with the same headlamp mount)...

..have to admit that its the first time i've heard of dynamo lamps being stolen, or perhaps that's because my all headlamps were made about forty year ago, have seen most of the chrome turn to rust and are now kept shut by a generous application of tape...guess the third option would be to simply disguise your nice new headlamp by making it appear busted and broken.. ' a street sleeper' as they say in the world of modified cars and motorbikes..

It doesn't help that some dynamo lights are priced ridiculously high in the first place.

I quite like the quick release idea, which is why I made sure for my DIY light it would terminate at a basic connector (a Tamiya connector - not waterproof, but that doesn't seem to be an issue). If you don't mind hacking at your light, you can put connectors in-line, and find a way of adapting a quick release from a bar mount light, so you can remove the head unit. A bit more creativity would be required for fork crown mounting.

Even more cool would be if you could use the terminals on a bike computer mount, so attaching and removing becomes one motion, and no wires are left hanging from your removed light. However, those mounts don't usually support much weight, and the connections probably aren't rated for 0.5A. Still, I could certainly see Supernova making a 'twist to fit' light using this notion. Hell, it could incorporate the cycle computer into it, as there's no reason why the dynamo waveform couldn't replace the standard bike computer if you could program in the number of poles (mind runs off with ideas... ).

If you have rear lights you can multiply the faff factor by about 3.

The downside, of course, you lose the 'fit and forget' aspect of dynamo lighting.

CliveyT wrote:I've learnt the local low-lives are going around stealing dynamo lights

Should I be worried? Whereabouts is it I've got to avoid leaving my bikes unattended?

I've be inclined to pack the allen bolt sockets with gritty mud or polyfilla, so that undoing the bolt involved 5 minutes poking with a pointy object

cycle tramp wrote:...the other thought which strikes me is to engineer yoru front dynamo light in such a way that it can be taken off and placed in your pocket... Clearly the wires to the dynamo light would have to have some water-proof, push-pull fittings to make connection easier, and perhaps use different coloured wires if you weren't using the frame as an earth connector, and then perhaps a simple bolt and wing nut... or if your were using an actual bulb rather than a light emitting diode, you could modify a headlamp that features a quick release that used to be powered by batteries...

this is exactly what I did Keeps the thieving sc??b?ags off it!

Sorry this doesn't answer your question, but I've just used a light with a sliding bracket, the usual kind of thing with a bracket that stays on the bike, and a two-pin connector - it's got a tab to ensure correct polarity but is still a bit of a faff to line up, since fitting it I've found the type in the second pic which is easier to use as you don't have to line it up.

PS the male-female orientation I've fitted it in is probably the wrong way round, as it would be more waterproof with the lockring coming up from underneath - each type of connector is different, but just look at it and work out how the water would run off it. The way I've fitted it, if water gets past the O ring, it dribbles into the contacts. I might re-do it!

Raph wrote:Sorry this doesn't answer your question, but I've just used a light with a sliding bracket, the usual kind of thing with a bracket that stays on the bike, and a two-pin connector - it's got a tab to ensure correct polarity but is still a bit of a faff to line up, since fitting it I've found the type in the second pic which is easier to use as you don't have to line it up.

PS the male-female orientation I've fitted it in is probably the wrong way round, as it would be more waterproof with the lockring coming up from underneath - each type of connector is different, but just look at it and work out how the water would run off it. The way I've fitted it, if water gets past the O ring, it dribbles into the contacts. I might re-do it!

I'm impressed...if ever i have to purchase a dynamo lamp for over 20 quid, then i think i'll be following your example.
Still abit surprised by the whole stealing dynamo headlamp thing. i mean, for a thief to use it, they'd have to have a dynamo themselves, and if they don't then they must be stealing them and then selling them on ebay or something (as clearly they're not usual items to be flogged in the pub or on market stalls), which would mean that there must be a type of cyclist out there who is prepared to pay for stolen goods, which is a little worrying...

cycle tramp wrote:"they must be stealing them and then selling them on ebay or something"

I'm sure that's right. Also, people steal stuff simply because they can - and think what to do with it later. Sadly often stuff gets stolen which is of huge practical or perhaps sentimental value to the owner, the thief can't do anything with it and it ends up in a skip.

The type of cyclist who buys stolen stuff off eBay is probably just you and me - we're not detectives and it's not usually advertised as stolen! Sometimes you can make a pretty good guess and steer clear, or the seller obviously hasn't a clue about what they're selling, which is a warning sign, but one can't always tell dodgy from legit.