Waterproofing rear lights - Smart Lunar

petemadoc

Picked up a couple of the 1 watt smart lunar rear lights on the cheap from planet x. Problem is these lights are simply not waterproof, go for a ride in the wet and it starts switching modes and can't be turned off.

Any tips on making this thing waterproof? I was thinking electrical tape but would like a better idea.

redvee

When Smart lights first came onto the market this was an issue back then, especially on the cheaper lights. I found a mud/splash guard helped as did a bit of silicone sealant. Another thing I found worked brilliantly was never ride in the rain

petemadoc

Yeah I was thinking silicone seal was a possibility. Downside being I'd have to break and re-seal every time the batteries need changing, plus I fecking hate silicone seal, it's all sticky and weird.

This is the light I'm on about

http://www.planet-x-bikes.co.uk/i/q/LIS ... rear-light



It's a shame about this waterproof thing because otherwise this light is the best thing going at this price.

ads2k

Can you not adjust th eposition you have it on the bike, say put it on the seat stem under the saddle so then it should only be getting 'road spray' and not direct driving rain.

Shame as I was looking at these and it's baby brother they have in the winter offer at the minute

petemadoc

The light is already under my saddle but general road spray always get in in the end. They really are brilliant lights other than this issue. They're so bright cars get a bit confused as to what you are and really slow down. I had one last winter but just lived without waterproofing it. This year I've got 3, 1 for the best bike and 2 for the winter bike. If you put one on each rear seat stay you look like a moped in the dark.

davenice

I'm wondering whether putting a thick (maybe 1cm wide) rubber band round the edges might help? Or electrical tape? Or whether water would still find its way under and it would actually just make things worse?

Thebigbee

I have the Smart 3 Led Kidney rear light and I have found it so waterproof I would actually bet money that I could drop it in a bowl of water, fish it out and it would still work!!

Got caught in torrential rain last week for about an hours ride. I had full "waterproofs" on and was soaked to the skin when I got back. Light was still flashing away!

If you really are worried about it I would silicone the join and then cover that with electrical tape. Should cost under £1.50 and there is then no way water could get in.

In my experience Smart light batteries last along time. It is not really a big deal getting a Stanley knife out to remove the sealant.

A tip when putting it on to make it easier to apply is to wet your finger with washing up liquid.

I don't see how you could do any more really. HTH

petemadoc

Thanks for the ideas

I think silicone seal is probably the way to go, after all it is designed to seal stuff. I think this will also look the least messy.

UndercoverElephant

Personally, I'd just coat the rubber band that goes between the two halves of the light with a little silicone grease (different to sealant). That should seal it completely, and wouldn't matter if you open and close it. That said, I've been using Smart lights for all weathers in the past two winters, with never a problem. Then again, I have mudguards when it rains.

bails87

UndercoverElephant wrote:

Personally, I'd just coat the rubber band that goes between the two halves of the light with a little silicone grease (different to sealant). That should seal it completely, and wouldn't matter if you open and close it.

I've done this on the Smart lights I've bought. Been using one for a few years for MTBing, they've been bumped around, soaked and encased in mud, and still work fine.

BigJimmyB

Clingfilm.

Cheap, easy and a doddle to remove/replace.

Works for me.....

kiwimatt

UndercoverElephant wrote:

Personally, I'd just coat the rubber band that goes between the two halves of the light with a little silicone grease (different to sealant).

Yep - I have the two LED version and it was playing up, fresh batteries and something like this http://www.ebay.co.uk/itm/SILICONE-MULT ... 2c5dd897af on the sealing o-ring and it's been fine less permanent than silicone sealant

ride_whenever

I'd also check the body isn't interfering with the switch. I had one which played up similarly, even in the dry and the body had been slightly distorted.

prawny

I just smear some grease ( I use lithium because it's all I've got) all around the outside. Works fine, never had a problem since I started doing that. Doesn't need re-doing every time either.

rolf_f

I always used petroleum jelly - again because I happen to have it. Just run it around each platic half, put the gasket in and close.

redjeepǃ

I used to smear mine with petroleum jelly...oh sorry wrong forum....

redjeepǃ

I'll start again.

The vaseline thing will probably work in the same way the silicone grease does if you smear it around the sealing surfaces, however it's meant to degrade rubber so the o-ring will probably have a slightly shorter life. I'm not sure if this will be noticable as I think you're taking years rather than months.

I've used it on a variety of bike lights over the years and it works well.

rolf_f

Redjeep! wrote:

I'll start again.

The vaseline thing will probably work in the same way the silicone grease does if you smear it around the sealing surfaces, however it's meant to degrade rubber so the o-ring will probably have a slightly shorter life. I'm not sure if this will be noticable as I think you're taking years rather than months.

I photographed my o-rings (oh dear) after a year or two of the vaseline treatment - in close up there was no sign of visible change at all. They may not even be rubber (seem more like soft plastic to me).

Nigel Bennett

I've only ever had problems with the Smart lights on bikes with no mudguards. Luckily, the failure mode on mine (so far) seems to be light on rather than off.

I've found that silicone grease is the best solution as I have a supply for use on Look pedals to stop the cleats squeaking!

meanredspider

It's incredible (to me at least) that Smart haven't done something to fix this themselves. It's a great light (just posted elsewhere about being able to see it at 300-400m in daylight this morning) but there's nothing worse than an unreliable rear light.

mudcow007

i use one of these http://www.thebikelist.co.uk/reviews/co ... rear-light

but have smeared grease all over the seals (fingers crossed) it seems to be ok....so far

rolf_f

meanredspider wrote:

.....but there's nothing worse than an unreliable rear light.

What about being clawed to death by cougars, bears and wolves?

memsley89

BigJimmyB wrote:

Clingfilm.

Cheap, easy and a doddle to remove/replace.

Works for me.....

That's the method I used also...
at first it was just meant for a temporary fix, but I've no reason to change it yet!