Iride01 

My son's been suggesting that a Garmin Varia might be a good X-mas gift for him. I've known about them ever since they came out and have read DC Rainmakers article on them.

Do you generally get at least 5 seconds warning on traffic when you are on roads with 50mph plus traffic?

How useful in slower city traffic is it?

My son thinks it'll also tell him about other cyclist coming up behind him? I can't find anything conclusive on this. I know Garmin only talks about cars and such. I'm thinking maybe it will if there is a large overtaking speed.

Any of you have experience with it coupled to the Vivosmart HR?

raqball

The radar will pick up other cyclist assuming they are going 10+ mph faster than he is. I think it's 10mph but it may be less than that. When I had it, it would easily pick up group riders when I was on the bike path.

Seattle Forrest

I find it useful. You can see the spacing between cars without looking back, have an idea when to merge, etc, while keeping more focus ahead. In the city with kids and pets and whatnot, I find that extremely valuable.

Beach Bob

I use mine all the time. It really isn't that useful in heavy traffic as it there are always cars going by...but anything less than that, it is awesome.

Out on empty roads, I'm normally getting 10 seconds or more of warning time.

And yes...a bike coming up behind you fast can set it off....

Cyclist0108

I like mine, and have found it has reduced the number of traffic altercations by reducing the surprise element, so it has taken a bit of the pressure off my middle finger. I ride mostly rural roads. It is most useful on downhills or when I am going fast enough that it is difficult to hear an approaching car. On windy roads, a car can be close behind before it is detected. In heavy-traffic areas, the beeping (I have it paired with an Edge 25) can get annoying.

Iride01 

Interesting that something like this doesn't stir up a bunch of controversy. I'm glad to hear that it does alert you well before the vehicle get to you. It probably will be nice for those times that the wind coming off the reservoir is playing havoc with hearing while traveling on the Natchez Trace and other rural roads around here.

wfp

I wanted to give it a try since I went blind in my left eye 10 years ago (makes the look over your shoulder move quite bit tougher). I like it a lot more than I expected I would. It gives plenty of warning.

taz777

Just be aware that Garmin Varia covers a range of lights. There's the Varia Rearview Radar light, which I believe is the subject of this thread, and there's the Varia Smart range which do not have the radar element, but still pair with an Edge cycle computer and will brighten or dim depending on environmental conditions and acceleration/deceleration.

Specifically the Varia Rearview Radar can monitor up to 8 cars approaching from behind and display them on your Edge or the dedicated Garmin Varia Radar Display Unit which you mount on the handlebar.

Anyway, I've just been out in the rush hour with lots and lots of traffic. The monitoring provided by the Rearview Radar was extremely comforting and useful. Just be aware that it monitors based on approach speeds exceeding a certain amount so a car may be immediately behind you but driving at the same speed as you. In this case it won't show up on the display so you still need too be careful.

I found that it gives me a bit more confidence, more awareness of traffic behind me and also makes most drivers pass more safely as the flashing light changes in intensity and frequency as a car approaches.

Seattle Forrest

It tends to when you talk about it with a wider audience.

The idea seems pretty stupid on its face. We're all accustomed to looking over our shoulder at traffic, and using the radar doesn't mean you can stop doing it. So, a lot of people balk at the idea. This has been my experience talking to cyclists offline, also there was some ridicule on here when the radar first came out.

But all of the criticism this system gets seems to come from people who haven't actually used it, just think it's a dumb idea. In practice, it's pretty useful, the value is just immediately obvious.

JohnJ80

I've had one almost since they came out. I've used it both as a standalone system and with an Edge 1000.


Yes, *almost* always. It's more useful on the highway than it is in an urban setting. That said, it doesn't look at traffic behind you, it looks at the difference in speed to objects behind you. So if you are, for example, riding at the same speed as traffic, then the threat behind you disappears. This, of course, can be disastrous if you make a hard turn in from of that same speed vehicle and get hit.

IMO, "much less" to "not much" and for three reasons:
It mostly will, BUT it's a deadly mistake if you don't look behind you. I find it far more useful on the highway in the country than in *any* level of an urban setting. My riding is primarily rural but passes through some small towns. In the town, it's not effective, but on the highway, it is more so. There is the problem of speed differential mentioned before and there is also the problem of how threats can be masked behind other threats. For example, if a truck is coming down the road followed relatively closely by a car, your display will show the truck threat and not the car threat. So you're missing one high speed vehicle behind you if you just believe the display.

Another problem is masking by curves. If you are riding around a curve, the Varia may not see another car coming behind you until it lines up behind you. In that case you will have much less than the 5 second warning you have become accustomed to. Basically, it can look behind you for about 450 feet (give or take) - do the math with respect to speed and if not in a relatively straight line back to you.

I don't think it's particularly useful as a standalone system and that it has a fatal flaw. When you use it with a Garmin bike computer, it will give you a beep (audio alert - wimpy though Garmin beepers are) when it picks up a threat when there was not a previous threat on the display. The standalone head unit that comes with a complete Varia system has no audio capability. I can't believe they omitted a cheap little beeper! You then just happen to have to look at the display to see if there is something behind you. I find that I get surprised just with traffic behind with the standalone system about as much as I would otherwise without a mirror.

I find a mirror mounted to my sunglasses to be much more useful (and much safer) but you have to scan it just like you would in a car - taking a quick look before any maneuvers and roughly once every few seconds otherwise. The Varia is no substitute for not looking behind you and can easily lead to false sense of safety because of the measurement of speed differential instead of absolute threat.

So it's useful, but you really, really need to understand it's limitations. If you don't understand those, then I think it's actually more dangerous. I got surprised by a car pacing me in a small town. I moved into the lane way, way too close in front of the car thinking there was nothing there because it didn't show on my display. I got a terrible scare and thank heavens that driver behind me was on the ball - she hit the brakes hard and didn't hit the horn. I got home, changed shorts (kidding), and called Garmin support only to find out it just looks at differential speed. Imagine my surprise.

J.

Iride01 

@JohnJ80 .... thanks for the write up. You and the others have given me a lot to share with my son. I think I'm finding out that it works pretty much to what my expectations have been. Many of his expectations are going down the tubes. But still it sounds like it's still in contention for a birthday or x-mas gift.

I'm liking the idea of it's potential to possibly get him out of a daydream while riding on a lonely stretch of the Natchez Trace or other rural road. Sometimes on the Trace, wind and noise in ears makes it hard to hear traffic behind.

Maybe I need one too.

JohnJ80

I forgot to add that it mostly won't see other cyclists coming up on you from behind. If it does, not until they are really close.

J.

Pug

I'd rate my experience with it 4 stars, holding back on the 5th because of this. While it can help with situational awareness you can't trust it 100%. It's additive to looking over your shoulder, not a substitute. This disappearing act is especially dangerous when a car closes the distance behind you but falls back to your pace or slower because it's unsafe to make a pass. In this scenario the car could be hovering 10 or 20 feet behind you, but the Garmin is showing all clear.

JohnJ80

You got me thinking about this. I guess to quantify what I think of this, I’d rate it as a 3-3.5 stars out of 5 for use with the Garmin bike computers. As a standalone system, I’d give it a 2.5-3 stars.

I think that the speed differential measurement and the loss of threats when speeds are identical is a fatal flaw (pun intended). It’s going to be hard for most users to keep this in mind and failing to remember or understand could have potentially fatal or at least disastrous consequences.

I take another star off for the standalone system version since it’s utility is dramatically decreased without the audio warning that you get when used with the bike computer. I, for the life of me, don’t understand why Garmin didn’t put in the same crappy little beeper they put in their computers - those piezoelectric speakers are dirt cheap.

But, it does help. Just understand it.

Canuk1w1

But seriously - good post. I want a new headlight and am considering a Varia.

JohnJ80

rgr555

does anyone use this in big urban areas? not sure what its for considering there are always many cars behind you. i do however find the light adjusting to cars as they come closer worth the cost...sort of

Seattle Forrest

@rgr555

It doesn't just tell you whether there are cars behind you, it tells you how the line is spaced. It's useful in a city because it gives you a better idea when you'll be able to merge. I've found it useful in Seattle.

Seattle Forrest

The drivers who wait patiently behind you for an opportunity to pass are the ones who are least likely to hit you if you move out into the lane. I agree it's not good, but it's probably not very fatal either.

I like using mine with a wrist watch for the reason you mention about an Edge beeping while the bundled head unit doesn't. The Garmin watches can vibrate on your wrist. If you configure them so they won't vibrate for any other reason while you're riding a bike, this is even more noticeable than the beep.

JohnJ80

As far as a taillights goes, it’s kind of lame. It’s only a 16 lumen light which is at best marginal. If that’s all your using it for, then there are choices for a fifth thenprife that are 10x as bright.

In point of fact, I keep it in my jersey pocket since it’s a bit wide on the seat post and can interfere with your leg on occasion. I actually wish it had the capability to turn the light off to conserve battery.

taz777

Do you have a Garmin Edge? If so, you can keep the radar function but turn off the flashing light.

Take a look at post #13 in this thread here: https://www.bikeforums.net/electroni...ly-option.html

JohnJ80

I have a Garmin Edge 1000 and I do have the app that turns off the rear light. This spring, I switched to the Wahoo Element for it’s better ergonomics and connectivity so now I have to use the Varia taillight as a standalone with it’s own head unit.

I’m interested in v2.0 of this. Hopefully Garmin is working on it. What I’d like to see is:

1. Brighter taillight. A good example would be like the Bontrager Flare with it’s focused optics and 60 lumen output. Same form factor would be good.
2. A smaller and more vertical form factor.
3. A head end with a beeper.
4. The ability to turn the light off.
5. Resolve the differential speed issue.

THe light world has it’s own level of innovation that’s hard enough to pace. It might be better to stick to being just a sensor and get out of the light business.