I have a Tacx I-Magic, and the speed sensor does not register the correct speed. I did do the calibration, and it appears correct. The Cadence is correct, and the watts appear correct. I know this beacuse my bike has a rear mounted cadence and speedometer (Cateye Astrale). So I am using my bikes known correct values when comparing the output of the Tacx on the screen.
The problem is that speed is only correct when climbing a steeper (2+ % gradient). When pedaling on a flat, it registers as much 5 mph greater than what displays on my Cateye. Why? Plus, going down hill, its as if the program knows this and displays downhill speeds (like 30 mph) even though the rear wheel is keeping a constant speed. Weird.
Does anyone have experience with this problem, or worked out a solution?
Otherwise, the Tacx is very cool. I paticularly like the live video rides of the TDF!
I entered my weight standlone, not with the Bike. I will try that as you suggested, though I cant see how that wil change the flats speed. But worth trying and I will.
Does yours measure speed correctly on flats? and Hills?
I wish this problem was just sporadic. Its all the time! Anyone else have an idea?
I’ve only had mine a week, but notice the speed is correct at 1.0. I also entered in MY weight. Im not crazy how it speeds up at the downhills, but as long as its constant and the HR and watts are correct, I dont care. If I am racing myself, its all good as long as its constant.
I did a LT test yesterday as 2x20 at the 1.0 incline and it was pretty spot on.
when you notice the speed difference, is the readout red or white on the iMagic? Red is sort of a virtual speed, and doesn’t reflect the speed of your actual rear wheel.
Yes, the speed box changes color. When the speed is white, it seems pretty accurate. When it reads high (or in correctly) the color changes to Red. From what you are saying, I glean that is normal?
I do agree with Klorene, as long as the HR and watts are right, thats what REALLY matters. But it bugs me to pay big bucks for this thing and not have it be perfect. We all like to see how fast we are REALLY going. Plus, I think it helps to have a reference point (or a constant) to measure your progress against.
yes, this is entirely normal. Since the iMagic can’t push you along in a tailwind or downhill it makes a correction to the speed readout. You should also be getting a lower virtual speed when climbing tough hills. If I remember correctly, you can only get a maximum of 7% grade or something with the green iMagic (higher resistance on the blue Fortius) so it’ll force you to either crank up the wattage or shift down to keep the speed up.
What type of computer our you guys using with your I-Magics? I researched for a few months and yesterday ordered the Fortius with steering unit. Hopefully it’ll work with this laptop. If not, I’m springing for a bare bones Dell ($400) that should run it just fine.
I like the idea of feeling speed increases on downhills which the Fortius will provide over the I-Magic with the brake unit. I also like the idea of the steering unit so I can go anywhere at anytime, make passes, etc.
I went to CompUSA and bought a simple Compaq SR2050NX desktop. Tacx recommends a mininimum of 128megs of RAM on the video card. The machine I bought ($500) had 250megs of RAM. Plus, I wanted a machine that has an S-Video output so that I can connect to an HDTV or a projection monitor. Right now I have it hooked up to the TV via S-Video and the picture is great! I am happy with the machine I bought, and its dedicated just to the Tacx.
By the way, I am building a cycling studio/work out room in my basement. I will mount a projector on the cieling and connect the stereo for a surround sound effect. The projector will display a 8’ X 10’ image on the wall. It will be just like being there. Cant wait!
You can use it on most newer laptops - but keep this in mind: If your computer is having problems, you can’t train. Yes, the iMagic and Fortius has NO resistance without a computer hooked up. Keeping that in mind, I’d recommend a cheap P4, a decent video card (6200 - 128+meg) fast hard drive and about a gig of memory. Find a free or cheap big CRT monitor (or get a TV card and output to a 25" TV) on Craigslist and you’re all set. In my experience, any P4 is enough; you need a good video card and a fast drive (especially for RLV since the video is completely stored on the drive).
Graphics card > fast hard drive > RAM > processor
I had a hell of a time when I first set up my system. I wasn’t planning on using audio so I disabled it. After trying for a week to get the software properly installed, I enabled audio and installed the drivers.
I just got my system and am still learning it for sure. I also had a hard time getting it installed properly, but with your advice and that of others it seems finally be settled and working corectly. Cool! Thanks!
One thing, I had a hard time getting the TV monitor to work with S-Video. If you go down this path, the video card has a view mode setting thats software selectable. Go to diplays, find the video card set up (mine is an ATI) and go to advanced settings. The view mode between monitor and TV can be found there. It took me two days to figure this out (even Compaq didnt know this). So hopefully this will save you some time!
Thanks for the info. I’m going to use my laptop and it should be fast enough. I’ll get a “projector” as a monitor and project the image “life size” on the dining room wall : )