Which BT cadence/speed sensor?
 

Hi,

I just bought a TomTom Multisport GPS watch and I want a Bluetooth cadence/speed sensor to use with it. I've found these that should work:

TomToms own model:
Cadence & Speed sensor - Sports Accessories - TomTom

Wahoo Blue:
Wahoo Fitness - Blue SC Speed and Cadence Sensor with Bluetooth 4.0 for iPhone 4 and 4S

Topeak Panobike:
Topeak® Cycling Accessories ? Products - PanoBike Speed & Cadence Sensor

Any thoughts on which is better? Any other options?

TIA!

I've only used wahoo and it's been nothing but consistent. I think they are regarded as the best in the field

I have three bikes all with Wahoo fitness S&C sensors on them for the last three years. No issues.

I also like that the sensor keeps it's own odometer internally that you can read with the Wahoo ODO app. This is great for keeping track of bike maintenance and actual mileage on the bike.

J.

I only have the experience with the Wahoo, both the S+C sensor and cadence only RPM. Both are great and have been very reliable with my iPhone.

Looking at the topeak one, it seems to lack the "arm" for the speed sensor - this might make it hard to line the main sensor up with the pedal and wheel magnet and get it close enough to register consistently for both for some bikes. I know the bike I put it on wouldn't have worked with out this.

One additional bonus with the Wahoo - the option of rubber band attachment vs zip ties is nice if you want to move it between bikes.

Yes but according to the user guide the distance between sensor and magnet can be up to 25mm! Which is quite unlike any other sensor I've seen, so I wonder how well it works.

Anyway, seems Wahoo is a safe bet then, thanks for the input!

Wow, 25mm!!!! I wish other sensors where that flexible...maybe it is worth considering then. Wonder why other vendors haven't gone passed the usual it almost has to be touching distance.

I got the Panobike last week and it has been working flawlessly and was easy to align both the cadence and speed components. Works like a charm on software and zero connection issue in over 125 Km done so far. I picked this one as I didn't like the arm of the Wahoo.

Ehhh, I had the Blue SC and it definitely was not 25mm. I had to get it pretty close, particularly with the cadence sensor part.

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The odometer feature was pretty cool though. I ended up switching to a Garmin Edge 810 due to battery life, but I was pretty happy with my Blue SC.

The 25mm was for the Topeak Panobike, not the Wahoo. Wahoo one definitely needs to be much closer then 25 mm from my experience.

You switched to a 810 as the battery life of your phone was to short? I started using the Wahoo RFKLT instead of my phone display. The phone battery with GPS on but screen off seems pretty good. Is there anything specific in the 810 besides battery life or turn by turn directions that gives it a significant advantage over the phone or phone/RFLKT combo?

Only been using the 810 for about a week now, so YMMV.

When using my phone (iPhone 5S) + blue SC on the Strava app with my phone turned off (normally keep it in my bento box) I would hit probably around 20-30% battery life after a 40 mile ride. This wasn't too bad but I don't like to cut it that close as I do generally ride alone and who knows.

I initially was looking at the RFLKT+ but I realized I was about to spend another $120 and be in the same spot with battery life. I also wanted turn by turn directions because it was a pain to keep having to pull my phone out to see where to turn next (and turn by turn on the phone would kill battery life even quicker). Since I already had the garmin cadence + HR sensor from an old running watch I just decided to bite the bullet.

Short test with a 15 mile ride yesterday left my Garmin with 75% battery life left. And that's after not charging it and using it for my commute on Monday and Tuesday (~2.5 miles each way if I take the light rail). Will be giving it a more thorough test this weekend :)

Wow, just realized I didn't address your question.

Upsides besides battery life and turn by turn?

Not too many, altitude is more accurate and it records temperature during your ride (woo!). You can also set alerts for cadence, heart rate, distance, etc. to remind yourself to either keep your cadence up or your heart rate reasonable. But depending on the app you're using you may already be getting this.

Also, If you're using the Strava app, it ignores the speed input of the Blue SC and is using GPS speed instead which is also less accurate.

Besides that, if you're happy with what you got, you're not missing much :)

Should also mention (though it doesn't apply to me) that the Garmin is waterproof as well. Though this could probably easily be solved by a fancy phone case.

Good to know about the Strava app and speed. I have mostly been using the RFLKT+ with the Wahoo app (but may try Cyclometer), which does use the speed sensor as well as GPS. The RFLKT+ has built in sensors for altitude and temp, give it an advantage over the standard RFLKT.

I actually debated between the RFLKT+ and a lower end Garmin (500 or maybe 510). Was buying a new bike and other stuff so couldn't spring the cost for the 800/810 for NAV (at least without also getting an angry wife).

Alerts sound nice, but may be a way to get them and not worth the extra $ to me right now. Eventually I may go for something with TbT Nav but for now I think I am good with my current setup.

As for waterproofing, the RFLKT+ is waterproof and my phone can easily go in a waterproof bag.

I do think battery life could become an issue for longer rides, making a dedicated option attractive longer term as well.

Cyclometer will do audio announcements if you want based on time, distance, ending a split or interval and on demand (those can be triggered by lots of things.. buttons on the rflkt, headphone buttons, etc...)

Good to know. I have been wanting to try Cyclometer out. Hope to do so next week.

I just got a RFLKT+. Received it last night in time to go riding.

It works well. After looking at the iPhone display, I have to say I do miss that but the LCD display on the RFLKT+ is pretty much equivalent to anything out there with that sort of display. It's easy to use, the button use is intuitive with the default settings with Cyclemeter. What is notable, however, is the battery usages is really much lower - less than half. If I had my iPhone display up all the way, it would drop about 40-45% in an hour or so of riding. If I turned it down half way, then about 30%. With the RFLKT+ on and the iPhone display off, it's about 10% (and that included a phone call). So based on that, albeit just a single ride, I'd have to say that with the RFLKT+, the iPhone's battery (if fully charged) is probably good for 7 hours or better.

Cyclemeter lets you design your own screens for the RFLKT+ and lets you customize the functions assigned to each button.

J.

Jarv Bluetooth 4.0 Cycling Speed and Cadence Bike Sensor for IPhone...

$35 on Amazon and works FLAWLESSLY with Runtastic Road Bike Pro.
Only drawback is it works with IPhones exclusively. Not a problem for me, but will not work with android.

My battery experience with the RFLKT+ is about the same. Roughly 10% drain on my iPhone on a ride that is a bit over an hour. This is with having cell service pretty much the entire ride. More mountain/rural areas might have worse battery drain as the phone would be searching for signal.

This ride: https://www.strava.com/activities/161451391

With the strava app, my blue sc, no rflkt, and phone screen off the whole time left my phone at 30%. Started at probably 80-90%. In total about 3.5-4 hours with breaks and all of that. Just used strava auto pause.