BigSean

Im trying to make a descision on which to get. I know many of you have the Garmin, but the IBike is $300 my price and it does a bit more. What would you do? https://www.all3sports.com/product_in...af7a4212e1bd84

voltman

I've read that the accuracy of the IBike is pretty iffy, especially for the price.

BigSean

Well, yes and no. Let me clarify that. My buddy is testing that and the $3500 SRM set up side by side on the same bike. All the readings are coming back identical. The only time the Ibike doesnt work is drafting or in a pace line(drafting again). He seems pretty high on it as a training tool. Thats what I would want it for is training. If Im out on a group ride, Im good with my HR monitor and a standard computer.

Extort

You would loose out on cadence, GPS mapping, HRM... but you gain a reliable power meter, temperature, and wind velocity...

HRM is 50 bucks (if you do not already have one), you can upload the route slip to a website and get GPS functionality, and a small wireless computer for cadence would be pretty cheap.

Exactly what data elements are lost when drafting?

voltman

Power and wind. The iBike gets its data from wind input.

Pico

I'm still not sold on the accuracy of the power meter on the iBike. It has to make a lot of assumptions that aren't always necessarily true. For example, it assumes that wind speed across your entire body and bike are is pretty much the same. But, while drafting that's not necessarily true since some parts of your body will be shielded from the wind more than others. If the iBike is in a local minima or maxima there would be significant error in the results.

I just can't see how you can accurately measure power without a device in the drivetrain sensing rpm and torque (= power).

BigSean

Here is a link of his first real ride with the SRM and Ibike side by side. It was pretty much a hill climb. But yoou can see from the graphs on both that they came up pretty close to the same. Perhaps waiting another year or so on the Ibike might be a better idea. But from this ride he did,it looks pretty decent. By the way, he doesnt pay for this stuff. They send it to him for testing and reviews. He is brutally honest in his reviews, and if he doesnt like something he will say so. The verdict is still out on this thing, cause he's been busy doing a 29er shootout. Yes, they sent him 8 different Niner bikes to compare. Im in the wrong business

rule

Go to the iBike webpage and click the link to their discussion forum before deciding. You will get a lot of accurate input on the pros and cons of the device.

I have been testing one for several months and comparing it my PowerTap. All that I can say is that by comparison, I could be really really really struggling were I trying to train with the iBike. There are way too many variables that I can influence during my ride that will grossly skew my data. The main thing that I like (and hate ) about my PowerTap is that there is no fooling it. It mocks me in any such attempts. The iBike, that's another story. Even with a bullet proof setup and calibration, I can do something as simple as sprinting out of the saddle, or just improving my tuck, and get a completely different picture of my abilities and power gains. Even with the latest firmware updates, the iBike unit is still very sensitive to imperfections and rough road conditions. For me in my chip and seal neck of the woods, there are a lot of places that I can ride and get no good data from it at all.

On the other hand, if you are just looking at the iBike from a gadget standpoint, it actually isn't all that bad at what it does. It is an inexpensive way to at least put some power data into your ride results. As long as +/-20% in certain situations don't bother you, it will work pretty much as advertised. The only complaint that I have that it doesn't seem to be able to handle given the current build is that the unit is extremely sensitive to the cold. The creators indicate that this oversight is a result of the unit being developed and tested in Dallas, 'and it doesn't get that cold in Dallas.' I live here too and sure didn't have any trouble identifying this weakness of the iBike on my inbound morning commute rides. There are a couple of things that you can do to help the unit with power drain issues on the battery during cold rides. One of them is in the settings but the other is a recommendation to change out the battery mid-ride. That has happened to me many times out on the road. It really isn't much help because once the unit starts to operate irratically all your data is screwed anyway.

So from a gadget standpoint, I agree with the other posts about what you would find more motivating and engaging. With Garmin you would get a lot of good ride data, just not a power read out number. With the iBike, you get a little bit of good ride data, including a representation of a power number.

That's just my two cents. Check out the iBike forum and see what you think.

Sir-Lanceimnot

+1 It makes no sense how wind is going to give you a power reading. What if you are ridding into a head wind? Makes no sense.

BigSean

Thanks, that is great information. Just what I was looking for. Sounds like I should wait or get the powertap.

Pico

A climb is the simplest situation for it to calculate power. All of the variables that are inherent in measuring wind resistance don't matter if wind resistance isn't significant. Climbing, especially steep climbing, is all about power and weight (baring any huge winds). If you know the weight and the speed of vertical ascent then you can easily calculate power. However, the iBike will only have accurate average measurements because there is a lot of noise in altitude measurements, just watch the grade bounce around on cycle computers and you can see that for yourself. A SRM or Powertap are the only choices if you are looking for accurate instantaneous results.