So this is a nice specific post then. If you are looking for a bit of intel on how to fit a Bontrager
On the other hand, if you’ve come for some general road cycling entertainment, then these are not the droids you’re looking for, Move along now.
So, for the roughly 0.1% of you that own a Trek bike with a hole in one of the chain stays, here’s a guide to installing a
And now an additional THIRD thing as I update this post. I madez a video. It is, after all, 2020, and we are stuck in our houses. So, either watch this YouTube dispatch, or continue to read and look at the pictures, your choice.
Yes, you are welcome for all the value I am giving you.
(Note: Some of the links in this post are affiliate links. It you click and buy something, I get a commission. You pay the same price.)
Step 1: Buy a
Duotrap Speed and Cadence Sensor
Bad news. The sensor doesn’t come with the bike. That thing in your chainstay is just for pretend (see step 2). I’m sorry to be the one that has to break this to you.
If you want one, you’ll have to shell out some cash. It costs around $60 / £40, depending on your monetary persuasion (okay, where you live…).
Here are the links:
Once the sensor arrives, you can move on to…
Important note: this post deals entirely with the Bontrager
Step 2: Remove The ‘Faux’
My guess is that the Trek design cadre didn’t want to sell a bike with a fug-off great hole in one of the chainstays. Instead the bike comes with a plastic ‘thing’ that resembles a Duotap, just without all the sensory gubbins.
Remove that by unscrewing the little screw on the front with a small hex key (or Allen key in my language) and then easing it out of the hole towards you (update: the bolt requires a size 2.5 Hex wrench/Allen key).
It’ll come slow and steady because the hole in the chain stay that faces the wheel has a rubber collar that fits quite tightly around the little plastic arm that you’re removing.
Step 3: Put The Battery In The Duotap
Hmm, this is disappointing. After using three photos in step two, I don’t seem to have a shot that shows the battery going in.
Anyhooze, it’s no great challenge. It takes a CR2032 battery, the flat round one about the size of a 10p / a quarter.
Step 4: Insert the Duotap Into the Hole In The Chain Stay
It should be pretty obvious how you insert the actual
Once the one true
Now it’s time to let the sensor see the magnet.
Step 5: Fit The Magnet To A Wheel Spoke
Like pretty much every other speed sensor, the
Some reviews suggest that the spoke magnet doesn’t come with the
If your one doesn’t come with a spoke magnet I wouldn’t worry too much. It’s a very small part that any bike shop should stock (and which they may well give you for free).
For this magnet (which I do think is the Bontrager one), you clip the two hinged sections of plastic around the spoke then tighten with a flat-headed screwdriver.
In terms of positioning, the idea is that the magnet passes as close as possible to sensor in the chainstay without actually hitting it on the way round. Prepare yourself for two photos that show essentially the same thing:
In case it’s not obvious, its the cylindrical arm that protrudes through the back of the chainstay that is the sensor.
I was a little bit concerned whilst fitting the magnet that it wouldn’t go close enough to the sensor. The spokes on my Domane have flattened profiles rather than being cylindrical (presumably because Trek know that I want to eke every ounce of performance out of this thing). This means you can’t fit the magnet in any direction other than flush with the spoke (ie. you can’t rotate the end furthest away from the spoke towards the sensor)….
…. Which turns out to be no problem whatsoever. The sensor arm picks up the magnet in this orientation. Panic over.
Step 6: Fit The Magnet To The Pedal Crank
This is more straightforward. The magnet that attaches to the pedal crank (which helps record cadence) definitely comes with the
The magnet is integrated into a glorified rubber band. You put this over the end of the pedal crank and move it down until it’s at the point where it passes the
Enough talking. Foto:
I think circle in the middle of the
As an aside, those two little dots to the right of the cadence sensor, before you get to the ANT+ logo, are lights. They flash (green and red I think) when the magnets on the spoke and pedal crank pass within range of the imperial probe and indicate that the
All that’s left to do is….
Step 7: Pair Your
Duotrap With The Cycling Computer O’ Your Choice
My choice is now the
Since you might have a different device, I’m not going to say much, other than that pairing the
Whatever your bike GPS persuasion, I’m sure you’ll be interested to see a photo of my
There you have it. Everything you could possibly want to know about how to fit a Bontrager
If you found this post because you’re looking to buy a
If this sort of thing (i.e. instructions for esoteric bike accessories) floats your boat, you should sign up to my mailing list to make sure you don’t miss out on future posts.
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Until next time, safe cycling!