Seatpost, seat pack and seatpost mounted light visibility

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Tangled Metal
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Seatpost, seat pack and seatpost mounted light visibility

Post by Tangled Metal »

Most rear lights tend to be seatpost mounted these days I've just got a really good one given to me but to use it I've got to remove my seat pack or the light isn't high enough to be fully visible from the rear.

I've got an xl bike so if my light is obscured then smaller bikes more so. What are the options?

My seat pack is useful for carrying repair kit. It's just in the wrong spot. Would be better if it could be attached at the base of the seatpost.

The light is a Lezyne laser guide light. I carry an inner tube plus topeak survival gear box in the pack. I have a rack plus single pannier, this rack is obscuring the light a bit.
Debs
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Debs »

Can you configure the rear light so it can be attached to the rear of your seat-pack?

I have the same sort of problem, but i'm working on the idea of getting a rear light which can be clipped onto the rear of my seat bag. I have seen seat pack bags on the market that have a rear loop for this purpose.
Dunno if it would work tho', it may result in a wobbly light if it's not firmly held on... if you know what i mean.
mattsccm
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by mattsccm »

Have you noticed that almost all seat packs with a loop actually point the light down a bit? Couple this with the fact that a clip in a loop always has some slack and thus downwards droop and you get a well lit back wheel. A mate has drilled out the seat on his TT bike and inserted an Exposure light which is cylindrical in shape. Every so often I start to think about grafting my Exposure lights clip to the seat pack clip.
Clip on seat packs do sit a bit lower and probably have room for this.
I have the same problem. Even a small pack virtually overlaps mudguards though when viewed from the rear most of the light is visible. Look from 50 yards away or more which is where a following vehicle will be.
An alternative is to graft a mount to the rear mudguard if fitted.
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mjr
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by mjr »

Tangled Metal wrote:Most rear lights tend to be seatpost mounted these days I've just got a really good one given to me but to use it I've got to remove my seat pack or the light isn't high enough to be fully visible from the rear.

I've got an xl bike so if my light is obscured then smaller bikes more so. What are the options?
[...] I have a rack plus single pannier, this rack is obscuring the light a bit.

Get a rear rack mount for that light or ideally a proper rear-rack-mounted light. If you didn't use panniers much, I'd say mount it on the stay.

Seatpost lights are [inappropriate word removed] in several ways (too hard to check they're still lit at a glance, too easily obscured by a coat or bag or anything on a rear rack, ...) and should be avoided. They probably sell a higher proportion of them to the UK because cyclists here are mostly [rude word removed] idiots about lights, with many acting as if a dazzling point light on a seatpost or seat pack is a good idea.
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
All the above is CC-By-SA and no other implied copyright license to Cycle magazine.
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chris_suffolk
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by chris_suffolk »

Because I have a seat post bag, I mount my light on the rear offside stay - never been a problem that I'm aware of
thirdcrank
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by thirdcrank »

I think the problem here is that the light itself is "seatpost specific" in that it's angled to go there and to be fastened with stretchy bands.

Although other lights which are supplied with brackets to fit there eg Cateye, do have other styles of bracket available: I have a Cateye on a seatstay on a bike with a small saddlepack. There's no point in having a minimal-clutter bike then fitting a pannier rack just to carry a rear lamp. IMO. Ditto the usual way of accommodating a seatpost-mounting lamp by fitting a bit of surrogate seatpost.
Tangled Metal
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Tangled Metal »

I have a clip mounted light to my pack as backup and use this new light with a rack mounted one. The rack mounted one is not that bright but good enough to be seen at night.

I could just leave this new light at home. I have two lights (possibly a third too) that I could use. However this is a much better light all round. It's good for daylight use and has the gimmick of lasers that produce two lines signifying "your cycle lane". It is a gimmick but for some reason when I've used it I've done a whole 7 mile commute in traffic without any close pass. That's not usual. I have only cycled one day with it so far.

I've got alternatives to this light but as it's a present and so much better as a light than I've got it really is a waste not to use it.

I think one solution is to get a bottle box or use the survival gear box mounted lower down the seatpost. That toolkit box comes with a mount for a round tube but I'm. Not sure how secure it is. I could pass the seat bag on to my other half and mount the light right at the top. Perhaps I could get a tool roll that can mount within the seat instead somehow.
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mjr
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by mjr »

Tangled Metal wrote:I could just leave this new light at home. I have two lights (possibly a third too) that I could use. However this is a much better light all round.

Clearly not - it seems it only has a stupid mount.

Tangled Metal wrote:It's good for daylight use

What's that mean? It's brighter than the winter sun?

Tangled Metal wrote:and has the gimmick of lasers that produce two lines signifying "your cycle lane". It is a gimmick but for some reason when I've used it I've done a whole 7 mile commute in traffic without any close pass. That's not usual. I have only cycled one day with it so far.

Could be a fluke. Also, do those lasers adjust so that the lines are actually 1.5m out from the centre line? Ones I've seen so far don't, so they probably make close passes more likely, as drivers may think that avoiding the line is sufficient.
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
All the above is CC-By-SA and no other implied copyright license to Cycle magazine.
Tangled Metal
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Tangled Metal »

It's not a minimal clutter bike. It's a touring, commuting, utility, off road, on road, family riding do a lot kind of bike.

This means it's got a pannier and rack (tortec expedition). I use both a lot (rack never gets taken off).

It is a seatpost specific light. Indeed it has one orientation only due to the lasers. If I turned it to put on a rack mount like my cateye it would fire out lasers to the pedestrians or the cars overtaking me. Only class 2 lasers so I can order it to cut close overtaking cars on half unfortunately.

It's totally the wrong light for me but I want to use it for what I see as valid reasons of not wanting to offend.
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mjr
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by mjr »

Tangled Metal wrote:Only class 2 lasers so I can order it to cut close overtaking cars on half unfortunately.

An earlier version being tested:
[youtube]Zx8rAniu_tQ[/youtube]
https://www.youtube.com/watch?v=Zx8rAniu_tQ

Tangled Metal wrote:It's totally the wrong light for me but I want to use it for what I see as valid reasons of not wanting to offend.

Could just avoid offence by not telling the giver it's wrong. If they cared enough about you to give you something, they probably didn't want to cause problems.
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
All the above is CC-By-SA and no other implied copyright license to Cycle magazine.
Roadster
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Roadster »

It seems unwise and inadvisable to compromise the performance of the rear light for any reason, least of all merely to avoid offending the giver of an inappropriate one. Your safety on the road is far more important than the giver's feelings and if the giver really cares about that, he/she will understand if you exchange it for a more sensible rack-mounted one.
Tangled Metal
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Tangled Metal »

It's a better light for the current trend for having bright rear lights on during the day to aid visibility especially when it might be raining or cloudy. It's a higher lumens light than I have. IMHO it's only the limited mounting that's an issue. If it's

The lasers might not be at the 1.5m gap but does that matter? It might be enough to give the idea to motorists that there's a section of road that's for this bike and cyclist. I'm not totally convinced it works but it it has that effect on just one motorist a day it's a success IMHO. Although I'd no way of proving it.
thirdcrank
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by thirdcrank »

I think your reasons for wanting to use this light are reasonable and certainly understandable, although on the inappropriate gift theme, I drew the line at not fitting a Halfords brake light on any of my bikes, well-intentioned gift or not.

I don't feel there's any benefit in ensuring others see you by dazzling them, but so long as the light isn't anti-social, I don't think you need to worry about it.
Tangled Metal
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Tangled Metal »

That's the nub of my question, what options to make it work? Other than replace the seat pack to allow higher location of the light which would make it visible and fully functional as designed. That is my only option which leads me to consider how to best carry roadside repair kit.

My current repair kit is the survival gear box from topeak plus an inner tube, patches, and a few more bits. I think the box toolkit came with a means to directly fix it to any round tube. The others will need stashing somewhere.

I guess there's no other way of using this light.

BTW it's not just avoiding hurting someone's feelings, it's a really good light. Lezyne make good kit no doubt about that. It's just a shame they limit rear lights to just one location unless you bodge it somehow. Visions of attaching vertical piece of old, cut down bars to the end of the rack. Possibly doable with all the specialist welding kit at work. Just a pain and a real mess of the rack I reckon. Easier to carry tool kit by another means and use the seatpost.

One thing that'll help, I'm sure my seatpost is slipping. I reckon it needs raising an inch or two.
Tangled Metal
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Re: Seatpost, seat pack and seatpost mounted light visibility

Post by Tangled Metal »

I think it's only antisocial on full power. That's 250 lumens. I had an 80 or 100 lumens rear light on when it was foggy. Didn't have confidence in it. Reckon I'll save full power for foggy days. That's definitely not antisocial then.

BTW I think 250 lumens is a bit too high for a rear light. I can get by with a front light that bright!
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