Does this rear light make sense?

[squeaker]

Thanks to gentlegreen for flagging this one up.

But is it a good idea or not - I can't make my mind up

[Mick F]

I reckon it's a gimmick.
How far away can you read the speed?
What use is it from the rear?

It's from the FRONT that I'd like people to know how fast I'm going. Cars pull out in front and peds step off the kerb not realising that I'm doing 15mph+.

[tatanab]

No -
1. as Mick F says it is those I am approaching who need to understand my speed.
2. you need normal lights as well.
3. motorist are likely to misunderstand since when they see a sign such as this it is usually telling them THEIR speed.

[meic]

On a more mundane level, the battery life is too short.

[thirdcrank]

My first thought was that I'd prefer to be able to display my own message, but that I reminded me that there's a fine line between being seen and attracting unwelcome attention. (I speak as somebody who has done a lot of cycling home alone in the small hours.) Things are a bit different in congested evening traffic, but the worrier in me thinks that unless these gadgets were in general use, it would be one more thing to enable the driver you upset but left standing in a queue of traffic to identify you, long after you had forgotten they existed.

[Mick F]

I take issue about the ANT sensor and GPS cycle computers.
It wasn't on the list of devices on my recently sold Garmin 705 - Speed/Cadence, HRM, Powertap - and it's not on the list on my new Montana - Cadence, HRM, Tempe (Temperature unit).

I wonder if a new ANT device brings itself up on the list and adds itself to it?
Somehow I doubt it, though I don't see why it shouldn't automatically update the list. Sounds like a good idea if it could be done.

[531colin]

I think its very interesting what people "see".....ie what they notice.
How many car/bike "incidents" are excused by SMIDSY.....and how many drivers complain about cycling RLJ's (I think they should complain about car and bike RLJs, but one of those seems to be OK.....)
Cycling in London in the sixties when few people did, I was "not seen" very often.....unless some lad in a car thought it was "funny" that I was wearing shorts. (These same lads are now to be seen in "barbecue attire"....ludicrous shorts and T shirts, with an immense belly prising them apart....but I digress....)
Generally, I think its a "good thing" to be seen, ie noticed, when on the road. The 3 most common dangerous incidents I get are close passes, passes where there simply isn't room, and "passes" where the driver cuts in long before they are actually past me. Its possible that this speedo light might help with the last 2 of those, where I think the driver's perception is that a cyclist moves at the speed of a pedestrian, or is effectively stationary.
Its very interesting that a woman I ride with doesn't get close passes.....she wobbles....
I'm much less concerned if people in front of me haven't "seen" me.....there is a fair chance I have seen them.
To paraphrase the "dragons' den"......I think I might be "in" on this one.

[samsbike]

I am not sure it will make a difference at all.

What would be more useful would be a light that creates the impression that you are wobbling around, that way the motorist may give more room.

Its also huge and I am not convinced it fit properly on the bike.

[Sweep]

Well that's a coincidence.

Or maybe not in the internet age.

I was nattering to someone who works with a load of international academic nerds just yesterday and he mentioned this to me - said one of his colleagues was keen on it.

I wasn't convinced yesterday and I'm not now.

That battery life (on a FULL PERFECT charge) is way too low.

And, gawd save us, it's USB rechargeable with presumably a built in battery - part of an awful trend in cycling lights getting too clever and going backwards.

And what if the thing develops a fault and starts reading 50 and someone just plows in the back of you?

[MikeF]

Well it's large compared with some other rear lights which is possibly one thing in its favour regarding visibility. How many motorists would realise it's the cyclist's speed, and at what distance can the figures be or are expected to be read? Would it be better run from a dynamo.
Is it legal??
I want one that can say "slow down you're in a 20mph zone" in big digits.

[SA_SA_SA]

Isn't it making the following driver do maths (their speed - displayed speed) = closing speed followed by working out whether to brake or pass.....won't that quite possibly delay the start of the drivers braking/overtaking?
and that's ignoring any pause when the driver might wonder if the displayed speed is theirs or the cyclists.

Surely the device itself should work out the closing speed and display "start braking now or move out to pass this cyclist"....i.e. do the drivers job for them

I wonder what the accidents that prompted its design were?

If distance judgement is the problem then two rear lamps vertically above each other might allow easier distance judgement or just a larger evenly illuminated area (eg like a B&M linetec Topline or more so: I would prefer the entire area of that lamp to illuminated (thus lamp size increased by the area of its reflector).

[Ayesha]

Audis should have them fitted as standard, with an auto overspeed signal to the police.

[sreten]

Hi,

Its nonsense. Drivers can tell how fast you are going by approach
speed from the rear, though if you asked them what speed they
would have no idea, consequently a speed readout is meaningless.

How fast you are going is generally indicated by your road position.
Downhill I've no problem riding about the third of a lane at speed.
Uphill at low speed I will hug the kerb. Its all pretty obvious.

Your telling drivers how easy/difficult you are to overtake.

rgds, sreten.

Most of your time your distance to the kerb indicates to
drivers the space they should give you overtaking. If
your going fast, move out to make them think more.
Most appreciate it.

[Drake]

Not to convinced about all the gimicky bits . . but a rear lamp that size seems sensible to me.

[Vorpal]

Hi,

Its nonsense. Drivers can tell how fast you are going by approach
speed from the rear, though if you asked them what speed they
would have no idea, consequently a speed readout is meaningless.

How fast you are going is generally indicated by your road position.
Downhill I've no problem riding about the third of a lane at speed.
Uphill at low speed I will hug the kerb. Its all pretty obvious.

Your telling drivers how easy/difficult you are to overtake.

rgds, sreten.

Most of your time your distance to the kerb indicates to
drivers the space they should give you overtaking. If
your going fast, move out to make them think more.
Most appreciate it.

It's much harder to judge relative speed at night, especially with small LED lights, which change less in relative size.

My distance from the kerb depends on whether I want drivers to overtake, though speed may influence that if I'm going 40 mph downhill, I normally do so in the middle of the lane. And I never hug the kerb. The inside wheel track is generally the furthest over I get.

I think its very interesting what people "see".....ie what they notice.
How many car/bike "incidents" are excused by SMIDSY.....and how many drivers complain about cycling RLJ's (I think they should complain about car and bike RLJs, but one of those seems to be OK.....)
Cycling in London in the sixties when few people did, I was "not seen" very often.....unless some lad in a car thought it was "funny" that I was wearing shorts. (These same lads are now to be seen in "barbecue attire"....ludicrous shorts and T shirts, with an immense belly prising them apart....but I digress....)
Generally, I think its a "good thing" to be seen, ie noticed, when on the road. The 3 most common dangerous incidents I get are close passes, passes where there simply isn't room, and "passes" where the driver cuts in long before they are actually past me. Its possible that this speedo light might help with the last 2 of those, where I think the driver's perception is that a cyclist moves at the speed of a pedestrian, or is effectively stationary.
Its very interesting that a woman I ride with doesn't get close passes.....she wobbles....
I'm much less concerned if people in front of me haven't "seen" me.....there is a fair chance I have seen them.
To paraphrase the "dragons' den"......I think I might be "in" on this one.

I agree. I doubt that most drivers will take much account of the actual speed. But it does two things that I like. One is that it may help drivers (even a few!) realise that I'm not going 2 mph. The other is that it works as a brake light, getting brighter as the speed goes down. I would *love* to have a brake light. I'm quite cautious about stopping suddenly in traffic because of nearly being hit from behind a few times.