RNAV

I'm hoping you smart folks can help me figure out a solution to a problem I've been having. I purchased a Bontrager Duo Trap S (new for 2015) with my Emonda SL8 Red. This speed/cadence sensor transmits in both Bluetooth Smart and ANT+. I paired it with my existing Garmin Edge 500 per Garmin's instructions.

Problem: I get multiple speed dropouts per ride, where my Garmin will show a speed of 0 mph, it will auto-pause, and then immediately auto-resume and register my existing speed. To be clear, this happens at speed (i.e. 15+ mph), and when I'm riding at a consistent pace. Also, I have had zero issues when paired with the Garmin speed/cadence sensor.

I'm on my second Duo Trap S (DTS) unit. My first unit would drop the speed 10-15 times on a 30-40 mile ride. The second unit averages 2-4 times per 30-40 mile ride.

Fault-tracing that I have already attempted:
1. Adjusted Bontrager-supplied wheel speed magnet location & orientation multiple times -- no change.
2. Replaced Bontrager wheel speed magnet with a super strong rare earth metal magnet -- no change.
3. Replaced cadence sensor magnet with a super strong rare earth metal magnet -- no change.
4. De-paired and re-paired DTS with Edge 500; ensured all other ANT+ sensors were off -- no change.
5. Replaced DTS battery with new, and different brand -- no change.
6. Every time speed is dropped, I'll hit the lap button on my Edge 500. I have been unable to detect any consistent timing between drops; the speeds are not identical; the cadence is not identical. In other words, it occurs entirely at random and I cannot ascertain any pattern to the drop.
7. Before every ride I spin the rear wheel & cranks, verify that the appropriate lights on the DTS illuminate to indicate that the sensor is reading correctly. I can hear the magnets actuating the sensor as they pass by. I also verify that my Edge 500 has recognized and synced with the DTS prior to beginning the ride.

Anyone have any idea or suggestions as to what could be causing this problem?

txags92

I would suspect something blocking the signal from the sensor to the Garmin. I have a blue tooth speaker that I use from time to time, and I know if I twist my body just the right way, it will block the signal from my phone to the speaker enough to cause it to drop. You can test for this by moving your Garmin mount from your stem onto the handlebar to the left of the stem. That will put less of your leg/body or the frame/stem potentially in the path of the signal. If that turns out to be the case, I don't know a long term solution other than maybe one of the small mount brackets that positions the Garmin out in front of the bars.

minnoce

I have exactly the same problem with my trek emonda sl 6, equipped with the new bontrager duo trap s speed/cadence sensor paired with garmin edge 500.
I'm using Training Center Garmin software for windows, and after uploading my rides I search the graphs for speed and cadence data looking for values dropped.
I've found a similar frequency of dropped speed values than you, but a significant more high frequency of cadence values dropped in the same ride.

af2nr

I've noticed this a couple times on my Emonda as well, paired with a Garmin 800. The first time I noticed it was on a ride at the beach, at which time my Road ID tracker also shut off, wide open area none the less? I noticed it again on Sundays ride which I didn't have the tracker on during. I recall it happening a few times on my R3 as well during rides in WV/VA, which I assumed was due to GPS issues?

On another note the rubber cadence magnet fitting for the Duo Trap S broke on me, it was in the driveway when I returned. It was a clean break and doesn't appear to be very durable so I'm looking for other options.

RNAV

I figured I'd update this thread.

So, 5 months later, same problems, entirely new bike, and I'm now on my fifth Duo Trap S (DTS) sensor that's been replaced under warranty. The significant change is that Trek decided to pair my DTS to a different Edge 500 (i.e. not mine), and that Edge didn't exhibit any issues.

I'm in contact with Garmin support. So far, they've suggested I delete the settings file from my Edge and re-sync with the DTS. I did that, and the frequency of speed drop outs increased on the next ride. Their next response was "if you run the Edge 500 in GPS-only mode and don't have any problems, then the problem is the DuoTrap S sensor." Well, obviously I'm not going to have problems with a sensor connection if I'm not connected to a sensor.

Just curious if @minnoce & @af2nr are still experiencing similar issues.

Btw, @af2nr, I use a rare-earth metal magnet stuck to my pedal spindle for my cadence magnet. Like this: linky

af2nr

@RNAV, I am still having the same issue with my Garmin and/or DuoTrap S. I really don't ever think about it except while I am riding, need to ask the LBS about it if I can remember it?! I ride the same route quite a bit and always mean to check to see if it is a "spot" thing or random? How is the new bike doing?

RNAV

In my case it hasn't been location-oriented. In fact, I haven't been able to correlate it to anything, which is quite frustrating for someone as persnickety as me.

Freaking awesome. You'd think that, being a replacement bike, it'd be exactly like the old one except that it works. Not only does this new bike work flawlessly, but the shifting performance is noticeably improved -- front & rear. I don't know if my old bike was setup poorly or had a bum gruppo or what, but this new bike's shifting performance is outstanding.

minnoce

Yes, i'm still experiencing the speed drop outs. Nor I had correlate it to anything.

Seattle Forrest

For what it's worth, I get what sounds like the same issue (speed reads 0 mph at random sometimes, while I'm traveling at speed) with a Garmin Edge 800 and Garmin speed and cadence sensor. It doesn't last very long but it happens often, and ultimately the data is unreliable.

I use the cadence sensor but I use GPS for speed. The data is more accurate at the end of the day.

My problem came up a couple years ago, I tried to troubleshoot it and never found a better solution than giving up. When I broke my speed/cadence sensor, I replaced it and didn't even bother to put the magnet on the wheel.

af2nr

That's kind of my thought too Seattle Forrest as mine happened on my R3 using the Garmin supplied equipment and is now happening using the DuoTrap S on my Emonda. However since I am off today I find this will be a good excuse to visit the LBS before riding this afternoon!

GaIslander

I have the same issues with the Duo Trap s and Node 1.1. Intermittent connectivity. I am gong to ditch the system go back to the old Cateye Micro Wireless which always worked perfectly. You want the Node and Speed Trap, you can have them cheap!

wreednelson

I've had issues with a Garmin 810/DuoTrap speed drop off intermittently since Nov 2013. I had no similar issues with the Garmin cadence units on my other bikes. Watching it yesterday, I noticed it the speed would drop out and the cadence was okay. And when I stopped pedaling the speed would go back to it's accurate reading. My magnet positions are perfect, new batteries, tried everything as the original posting did. I think it is the DuoTrap, which I will now dub DuoCrap. I am going to take the wheel magnet off and just use cadence. The GPS has a little speed lag. I can live with that. What I can't live with are the high $$$ devices that are buggy as hell and have user interfaces that are different, even within the same brand. I am not that much of a Garmin fan either after my experiences, but there are few options in the market that are better... which is scary.

GaIslander

Just like SeatleForest and Wreednelson suggested I ran the Duo Trap without the wheel magnet. The Garmin 500 works perfect with maybe a slight lag in the read out, but its not a problem. Simple solution. Thanks guys!

MikeIndy

I am seeing this issue as well. Seems to be a new issue. I had not noticed it last fall in about 2000 miles. This year I'm little over 2k miles. In Indiana most of the miles to date were on the trainer. Depending on what I was doing I might not have been using the Garmin (Trainer Road or Zwift). With the improving weather I'm getting more outside miles. Now I am seeing the issue somewhat frequently. Mostly on solo rides when I tend to look at the head unit more often. Can't say for sure if it wasn't happening on group rides or not, just hadn't noticed.

I have a Stages PM on my Shimano DA crankset. it includes a cadence sensor. I'm wondering if there is a conflict occurring. It uses BT, not ANT+. Seems like since the only speed sensor is the DuoTrap a conflict 'shouldn't' be an issue. When I see the issue, I disable the DuoTrap and ride on.

Thoughts?

Kikos4me

You guys are not very encouraging. I just bought a new Trek and was thinking of purchasing the duotrap s. I planned to us it with my phone app (no remarks about using my phone). Now I'm not too sure.

Wheever

Not to dig up and old thread, but I just started having this same dropout problem with my duotrap s and a couple different apps on my iPhone 6. (Cyclemeter and trainer road.) did anyone get a response out of Bontrager about this problem?

Mossatron

Digging up and old thread here, are people still having issues with bontrager sensor?


I'm buying a garmin comp and looking for info on what to pair it with, the garmin sensors that come in the bundle or the bontrager sensor that I can integrate into my frame.


Any pros/cons?

Iride01 

You will always find people that have issues with any product. Most naturally it's only the ones having issues that are going to post. Very few will post just to say they've had a great experience.

Go to any forum devoted to Garmin, Polar, Wahoo or whoever has a forum and you'll think that for certain none of their products are any good if you go by the number of rants you find.

SUNCOAST

I have a 2017 Trek Domane SLR 6 with the DuoTrap sensor. I have over 7K miles on that bike and up until recently, I had no problems with the speed and or cadence dropping out. Now, I have those intermittent problems! I am using a Wahoo Element Bolt. So, after reading the preceding posts, I doubt it has anything to do with the head unit but, is in fact the DuoTrap itself. I use the same Bolt computer on three other bikes with Wahoo sensors and or power meters with no problems. I've tried various troubleshooting ideas as expressed in this forum to no consistent avail. I haven't replaced the original DuoTrap as of yet...but, maybe I will.

I'll be watching this thread...

fourfa

FWIW I have a Garmin on an out-front mount, and I used to have a dual SPD/CAD sensor on top of the chainstay. I got sick of accidentally knocking and displacing it too often, so I got separate CAD and wheel SPD sensors. Initially I put the wheel sensor on the back hub but it took forever to sense the start of a ride and had frequent dropouts. Moved it to the front hub, and haven't had a problem since. I assumed the distance and body mass in the way was just too much for it. Sounds very similar to what's reported here. It's a shame if so because the hidden sensor is a real cool feature

horn1977

FWIW, my 2014 Domane 4.3 has been in the shop for the last two weeks - took it out for its first post tune-up ride last night and had the same problem, and again tonight. Never had the issue before. Now connection randomly flakes out. Recorded a known and frequent 25-mile ride tonight at just over 23 miles. So I guess what I'm saying is I wouldn't rule out at all that this is some kind of wonky firmware issue with the Bolt. I have noticed this spring that Wahoo has been *super* aggressive about pushing out firmware updates. I think I've been nagged for more of those in the last two months than in the previous two years put together.

I'm going to try to reach out tomorrow to Wahoo about it. Technologically speaking, that DuoTrap is a pretty "dumb" piece of technology. It's a couple of magnetic sensors attached to an ANT/Bluetooth antenna.

horn1977

So just a quick update here - I spoke to Wahoo today (and should add, they're super responsive and very friendly). Their suspicion is that it's a firmware issue.

To clarify my issue - I did some exploring while on the phone with them.

- Duotrap was reset by inserting the battery backwards for 30 seconds.
- Fresh battery went into Duotrap.
- Bolt *only* drops when pedals aren't moving. IOW, when it picks up cadence input, everything is good. When you stop turning the pedals, the input drops, and doesn't pick up again until the pedals start moving.

And the kicker that helps to address the diagnostic issue...

- I reconnected my old Bontrager Node to the Duotrap and it's just fine. I can put the two units side-by-side and watch the problem occur with the Bolt while the Node just keeps coasting the speed downward.

So you may want to reach out to Wahoo and let them know you're having the problem too. My $5 says their most recent firmware update borked something that is causing the Bolt to stop reading the speed input from the Duotrap when it's not also getting a cadence input. They thanked me for my patience and help and took my email address so they could send an update after they talk to their developers.

Hope this is helpful to you, Suncoast, and to others who might read it.

horn1977

From Wahoo Support:

"Hello,

Thank you for contacting Wahoo. I verified with the developers and yes, we have a current error with the last update that is creating problems with some sensors. They are currently working to fix it, but we don't have an exact date when it will be available. We are so sorry

When it becomes available, an update will be available to solve the problem

Thanks for your patience and cooperation."

drewguy

Yeah - had this exact problem with Wahoo Bolt and Duotrap, and got similar response. They seem to have fixed it, but now I'm having problems with Bolt dropping connection to iPhone and not syncing.

horn1977

Yeah, the last firmware upgrade a few days ago resolved it. Can't speak to the iPhone issue. But like you, I've noticed that the process of pushing Bolt data through to Strava via my iPhone has been a bit clumsy lately. Sometimes I have to power the Bolt down and back on, or quit and reopen the Wahoo app on the phone. I've never *not* been able to get it to transfer with some fidgeting.