TimothyH

I've purchased a VeloComputer speed sensor and hope my thoughts might be helpful to someone...

I've been looking for Bluetooth sensors to use with an HRM/GPS that doesn't support ANT+. Easy enough but most Bluetooth sensors use magnets and I'd really like to avoid spoke magnets if possible. So far the only options I have found are the VeloComputer speed and cadence sensors and the Wahoo RPM cadence sensor. Wahoo does not seem to make a magnet free bluetooth speed sensor.
The VeloComputer speed sensor was $22 on amazon so I bought one. Pics and my experience so far below.







Someone here said they weren't too fond of the ladder style mounting, specifically stating that it felt like it would break when stretched. I find the rubber no different than what comes with a Garmin speed sensor. It is a weird design though and time will tell. Notice the separate curved rubber piece hub mounting.

The sensor goes into DCU mode for the first minute after installing the battery. DCU mode is for updating firmware. After that it searches for bluetooth or ANT+ devices and begins operation. The light is supposed to flash at different rates depending on whether it is in DCU mode, connected to bluetooth, operating, etc. I found little to no difference in the rate of flashing depending on mode.

Setup was a no-brainer. My iPhone 6 found the speed sensor on its own with no pairing and the Strava app was able to attach with no problem. A ride around the block confirmed that it worked properly.

One neat (and cost saving) feature is the ability to update firmware. The only difference between speed and cadence sensors is firmware - they are the exact same hardware. I tested it by using the cadence sensor firmware to flash the speed sensor. VeloComputer documentation is not good and instructions were a bit confusing but once I figured it out, the actual flash took less than 15 seconds. The unit immediately showed up on my phone as a cadence sensor. Another ride around the block confirmed proper operation.

The ability to change a speed sensor into a cadence sensor via firmware is significant in terms of cost because the speed sensor is $22 on Amazon while the cadence sensor is $49. Please post if you find it cheaper somewhere else. Why buy the cadence sensor when you can buy the speed sensor for half the price and turn it into a cadence sensor? Why the difference in price? I don't know.

Note that the sensors do both ANT+ and Bluetooth LE/Smart. I have not tested ANT+ but will post if I do. Also note that there is a high precision bluetooth only version of the firmware but that is for use with the VeloComputer app only.

Below is a pic of the Garmin ANT+ sensor and the VeloComputer sensor together on the cranks of my fixed gear bike. This bike doesn't have a lot of clearance between the cranks and chainstay and so it illustrates the size nicely. VC recommends two sided tape if there isn't enough clearance when using the rubber housing. Garmin at the top of the first pic, VeloComputer at the bottom.





Garmin on the bottom. I haven't cut off the rubber "ladder" yet.



I wish it was a little thinner, especially with the rubber housing. YMMV depending on crank-chainstay clearance. My biggest complaint is documentation. The VeloComputer website is horrible and google is your friend. The manual for the device is at https://velocomputer.com/ws/rest/upda...UserManual.pdf..

I'm very hopeful that two of these sensors will work with the Polar V650 bluetooth only HRM/GPS as a solution without magnets. I'll post more to this thread if I get any new info.


-Tim-

voorstad

At the CES, I bought both the cadence and speedsensor. Currently I am using them with my smartphone, but I am looking for a better solution (Polar V650 / M450 / Wahoo RFLKT). I've contacted Soundofmotion (Velocomputer) and they replied to me:

"We have users with V650 which reported to us that they work with VeloComputer Smart Sensors. As long as Polar uses standards like Bluetooth Speed and Cadence profile and design their products that they can use 2 separate sensors, one for speed and one for cadence both sensors shall work fine."

I am considering the Polar V650 too, but the lack of smartphone bluetooth syncing with Polar Flow (Polar:" It's coming for sure, no date to give. We'll keep you posted!") is keeping me away from buying the V650 yet.

I agree on your observation that the mounting is a little weird. Also the lack of documentation and horrible website is an observation I totally agree. Marketing is not their strongest point yet.

John_V 

FYI - Other than seeing a V650 on the bike of one of the regulars at the park, I don't know that much about them. However, when he was showing it to some of us, he did mention that he had to give up an expensive pair of polarized Oakley's to be able to see the screen. I saw the screen just fine, but my sunglasses are transitions and are not polarized. If you ride with expensive polarized sun glasses, you may want to take them with you when you go to purchase it and see if the same holds true for you. He purchased his on-line, sight unseen.

John_V 

If you are already using them with your smartphone, why not just go with the Wahoo RFLKT if what you want is a display of your data without having to keep the screen on your phone on? Both Map My Ride and Ride With GPS have turn by turn features in their app, if that's what you are looking for. If you really need to see your current location, look at your phone app. Not to tell anyone how to spend their money but I honestly can't see why so many cyclist, that carry their smart phones with them on all their rides, want to duplicate what their phones can do with standalone GPS computers. And let's not get into the battery life issue of a smart phone because, if set up correctly, that is not an issue.

TimothyH

@John_V, this thread really isn't about the V650 but about the VeloComputer sensors. $22 for Bluetooth and ANT+ sensor is compelling.

The V650 is why I bought them however, and your point about polarized glasses is good. I hate them. My prescription riding glasses are not polarized for the reason you stated. Thanks for that.

John_V 

I guess I took it that this statement meant that you were also looking at getting the V650. Must have had a senior moment and didn't think that you may already have one.

JohnJ80

I had bought the sensors a while ago to use in BT mode with Cyclemeter on the iPhone. I was not able to get them to work and could only use one VC sensor at a time. I don't know if that was a Cyclemeter or a VC problem, but the guy from VC was not helpful in trying to solve the problem or particularly responsive. I finally just gave up and returned one of them back to Amazon. When I posed a review describing my problem, then he suddenly wanted to work on the problem. So I'm not particularly impressed with the company (one man band, I think).

I also had one of the ladder rubber mounts break. The mount is a good idea but it is not as substantial as others. I broke the one on the crank where is is relatively unprotected (as compared to the hub). I ultimately went with the Wahoo sensor which also does both ANT+ and BT and works seamlessly with Cycelmeter in BTLE mode. Further advantage is that the sensor can be securely mounted with zip ties. Wahoo is rumored to be working on a hub mounted speed sensor but does not have that out yet.

So ultimately, I think the VC sensors are an interesting product but that they are really not yet ready for prime time. The advantage to them is they have more resolution than most other accelerometer based sensors but only if the head unit is set to run with the higher resolution which virtually all are not.

The Garmin sensors are pretty much bullet proof. There will be a lot of accelerometer based sensors coming out shortly so I would expect that the VC sensor will probably not survive in the face of more established company's products and marketing muscle.

I have to tell you though, getting rid of those &$&$^%$# magnets was a special joy for me.
J.

ypsetihw

so you have to buy two of these to use one for speed and one for cadence? this will upload cadence data to your strava rides? do you have to input wheel size I assume to make it accurate? does this override the speed data calculated by strava using cell signal?

TimothyH

Based on this post I can tell that you get it.

Thanks for the info about the company and support as well as the rubber mounts. The Wahoo cadence sensor looks nice but is twice the price - might wind up going that way if I have the same experience as you.

By the way, the Garmin speed sensor is not an accelerometer. It is a magnetometer which measures orientation against the earth's magnetic field. There was a link to a Garmin support document explaining this in another thread about faulty speed readings when riding over bridges constructed with steel beams.

Really looking for a solution with out magnets. Joy is an appropriate word.


-Tim-

TimothyH

Yes, two are required.

It sends data to your "head unit" which can be a phone with an app like Strava or a dedicated bike computer like the Polar or Garmin devices. Ultimately the head unit sends data to online services like Strava. The sensors will not send data directly to an online service.

The speed sensor will be more accurate than cell signal or GPS satellite. The speed sensor only measures rotation. The speed sensor does not know how big your wheel is. Wheel size is a function of the app or dedicated bike computer head unit.


-Tim-

JohnJ80

I continually forget that the Garmin units are not accelerometer based - thanks for reminding me (now, lets see if I remember .... again). It's kind of surprising given how cheap accelerometers are now because of their inclusion in volume products like cell phones.

On the VC sensors - looks like VC uses the Nordic Semiconductor chip from the same family as Wahoo uses in their device. Both show up in the utility app that VC uses to update or change the profile on the device. I also might add that when using one of each (VC and Wahoo) looks like they conflict with each other. Why? I'm not sure. Neither company was helpful in debugging that and there is no way that is going to get solved without one or both figuring out if they were the problem. Both insist they are ok. So that's going nowhere fast. Mixing manufacturers is not a winning strategy.

I've been riding with magnets on my wheels and bikes for decades and have hated them for just about as long. I never fail to bump something out of alignment when taking a bike off the car and it's aggravating. These new sensors solve that problem so nicely.

J.

dr_lha

I bought one of these for $35 a while back and ended up returning it. I just couldn't get it to work reliably. It would work once, and then it died. It especially didn't seem to like being in the presence of a Wahoo cadence meter, which just killed it dead. Often it would not start up by itself, and I'd have to remove it from my bike to get it to respond.

In the end it was more effort that it was worth. My Wahoo speed/cadence sensors just work, without issue. This did not, and the best that the company could suggest was to use it with some Cateye software instead of Cyclemeter/Strava/Wahoo Fitness apps, which is a shame because the Cateye software sucks a**.

Sometimes cheap isn't good value.

JohnJ80

Yeah, that's weird that it seems to conflict with the Wahoo RPM. I had the same issue. Really odd since I think they both use the same part. You'd think that the BTLE software stack from the chip mfg would be pretty thoroughly debugged. But apparently not or it's a bad implementation from VC. You don't hear to many complaints about the Wahoo stuff.

J.

dr_lha

I've got a mix of Wahoo and Scosche BLE devices on my bike, and they all work together fine. It's hard to imagine that the widely used and generally praised Wahoo devices are the ones at fault.

JohnJ80

That's my general thought too but I'd have to have some help or some ability to get into the guts of either the sensor software or Cyclemter to definitively make that statement. That said, I'd bet money you're right if you're going to make me guess.

J.

voorstad

As Polar will add the Bluetooth Smartphone sync with their next firmware update, I decided to go for the Polar V650. I connected the Velocomputer speed and cadence sensor, so far, so good. When riding, not a single signal came through: no speed, no cadence. I updated the firmware again of the speed sensor (although I was on the latest), and tried again. No luck again.... left a message with Velocomputer / SoundofMotion, no reply yet.

Disappointing...

dr_lha

Sounds about in line with my experience. Return it and buy the new Wahoo Speed sensor, which is $40.

JohnJ80

Yep. Me too. Basically, I believe Velocomputer is a one man band company where the owner is doing this in his spare time. There is a lot of momentum building in the cycling instrumentation side for magnet free sensors. If he doesn't make changes ASAP, he's going to be left way, way behind. Already, it's been a year and it sounds like he hasn't updated anything or has no new answers or new efforts to make this work with the popular computers and phone apps. Based on that, while it's good idea, I've written them off and don't expect them to survive much longer.

J.

clydeman

I picked up one of these speed sensors a couple months back and reflashed it to work as an ANT+ cadence sensor and so for it has worked fine, not bad for $20. I want to comment on the response of the business or owner, it is non-existent from what I have experienced. I have emailed the company twice to ask a couple different questions and so far no response. So I don't recommend their products because there is no support.

On a side note, these can be found cheap enough to be considered disposable, I just picked up 4 additional speed sensors for $15 each. I plan to use two on another bike for speed and candence and keep two as backup in case of failure or loss of the ones in use.

JohnJ80

Sounds like he's getting out of the business. They probably work fine on ANT+ but they don't work properly on BT LE. And it seems that the lack of support is unchanged and is still nonexistent.

I might as well have just flushed the money down the drain for the two I bought. Didn't work and the guy/company (one man band) was useless in helping.

j.

Road Fan

Why are magnets a bad thing?

JohnJ80

I continually have alignment problems with my wife's bike and mine especially after transporting on a car rack. The alignment problem manifests through no data to the head unit. This problem is gone with the magnetometer or accelerometer based sensors that don't require a magnet.

J.

TimothyH

Yes, I got a Polar V650 and the velocomputer sensors don't pair.

So yeah, the sensors have sat unused for many months.

Live and learn. Maybe i'll use them on a trainer with an old iphone or something.

JohnJ80

Don't bother. They don't work with the iPhone either.

TimothyH

They worked with the Wahoo app on my iPhone 6 FWIW.