Varia V3.40 The radar detection distance becomes shorter and dull

I've been more than happy with my radar since I got it.. I absolutely love this thing and won't ever ride without it again. Heck, I had a ride where I forgot to charge the battery and it died mid ride. I felt naked the rest of the way home without it. LOL

My biggest problem with 3.4 is multiple vehicle detection. This is a #1 top priority for me as all of my daily my rides are in medium to heavy city traffic..

My setup with the Radar and a Virb....

Nice bike. Curious-what is the height from ground to center line of your Varia light??? Mine is 38 inches. My light is even in more close proximity to my seat bag than yours. Just an observation on my part but your light seems to be pointed very slightly down in your photo but I wouldn't think it would impact performance.

34" to the center of the RTL and no it's not pointing down. The height is fine or I would have had the same 3.4 issues on 3.0...

Thanks, I've put a lot of miles on that bike since I got it Jan 2014. I ride about 30-40 miles a day 6 days a week...

My setup with the Radar and a Virb....

I also ride with Virb camera's, usually Virb X front Virb basic or Virb Elite rear, it would be useful to link the Varia to the rear Virb to trigger recording (probably too much lag before recording starts), or at least mark on the video when the Varia actually detects something.

This may be only perception on my part but V3.4 also has indicated to me to be more perceptive in picking up approaching bicyclists. I ride on bike paths from time to time and just seem to get more triggers than previous versions. I know there are a lot of factors at play here like slower closing speeds and smaller surface area to detect. Really fast cyclists fail to give warnings when they pass me on the bike path so this is helpful. I have no test data on my part but just an unscientific observation.

Not so sure I'd want the unit picking up other bikes.. I occasionally get on the path and when I am passed the speed difference is not by much. I think the radar does not even alert to cars that are less than 10MPH. Is that correct? If so then I assume bikes would be the same 10MPH?

Either way, most cyclist on the path that are going fast enough to pass will say something to alert you to their presence anyways and I can actually hear them coming most of the time because of the lack of road noise..

If 3.4 improved bike ID and you are happy with that then cool! I don't think it would be something I'd want though..

Not so sure I'd want the unit picking up other bikes.. I occasionally get on the path and when I am passed the speed difference is not by much. I think the radar does not even alert to cars that are less than 10MPH. Is that correct? If so then I assume bikes would be the same 10MPH?

Either way, most cyclist on the path that are going fast enough to pass will say something to alert you to their presence anyways and I can actually hear them coming most of the time because of the lack of road noise..

If 3.4 improved bike ID and you are happy with that then cool! I don't think it would be something I'd want though..

10 mph is not correct but close. As stated in Garmin Varia Owner Manual Page 3 for radar detection and quoted verbatim:

Radar Detection:

"The approaching vehicle speed must be from 10 to 160 KM/hour(from 6 to 99 miles/hour)". You were probably thinking in metric units.

Slower cyclists are not picked up by the radar but the fast ones are. Cyclists in your area are more courteous than mine. Very few times are warnings given and some close calls have incurred so any advanced warnings are appreciated by the radar.
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Ahh cool... So anything greater than 6 mph over my speed should be registered.. In that case slow vehicle detection is even worse than I thought as I was going off of a 10 mph base line...

Bummer on rude cyclists. Every so often I am passed on the path by someone who does not give warning but I usually can hear them due to the lack of road noise. I don't think my unit has ever picked up a cyclist passing me on the path but again, when I do get passed it's generally on a few mph faster than I am going.

I can see that being huge though if on a family ride with children where your speed might be slow..

The RTL is looking for a relative approach speed and not an absolute speed. It will only report targets where the approach speed is above a given threshold.

Using Google maps and Apple maps to measure distance is about as unreliable as you can get. I'd say your testing would be considered 'ballpark range' or maybe, sort of, kind of ...

Not really. I verified the detection distance at my first test site using a rollout test; and just for comparison, also by GPS, both on my Edge 520 and my iPhone.

The detection distance as measured by different methods:

• Google Maps - 525 feet
  
• Apple Maps - 500 feet
  
• Rollout* - 508 feet
  
• GPS (Edge 520) - 470 feet
  
• GPS (iPhone) - 500 feet
  

(It's probably normal for GPS to slightly understate the number for short distances like we are discussing here).

* Rollout test using properly calibrated speed/cadence sensor (Bontrager DuoTrap) with wheel size set to 2096 mm. And given that rollout is probably the most precise of the three verification methods, I've shown the exact recorded number (without rounding to the nearest 5 or 10 feet).

So my conclusions about Varia radar firmware ver 3.40 remain unchanged:

• The detection distance is 500 feet or greater; and
  
• The detection distance is not affected by multiple vehicles. That is, the detection distance is the same whether a single vehicle or multiple vehicles.