Tacx iMagic Fortius Trainers

Velonutter

Anyone got one? I'm thinking of one for this winter rather than my fluid trainer, it's a lot of money, but wanted to check opinions first.

http://www.tacx.com/producten/vr-traine ... /index.dot

Are they reliable as well?

Where's the cheapest place to get one from?

neeb

Been using one in Finland during the winter for three years plus now, it's been a godsend, although be prepared for a few headaches setting it up and sorting out occasional hardware and software issues.

If I was buying again I'd probably go for one of the newer Bushido units - a lot easier to setup, quieter apparently, and can also be used as a trainer without needing to be plugged in to a computer. It's also cheaper. Only disadvantage is that it doesn't power itself going downhill like the fortius does, but I don't think I'd miss that much.

brettjmcc

Had one for the past couple of years. I like mine and got it cash for £300, but then had to spend another £80 on the TTS3. As above, it's a bit of a pain when I take it to club turbo, but I have it down to a fine art so not much of an issue (unless my wife takes the laptop with her)
I also like the power graphs, analysis etc, but it just plays to my inner gadget geek.

If I was buying again, I'd probably go for one of the newer models, but I can't see that happening for a long time

Velonutter

Thanks Lads, its the newer model I'm looking for with the new steerer, just difficult to find one under £850

mac220

Hi,

I've had a tack imagic in the past and I think the key question in terms of how good it will be depends on what you ae going to use it for. If you are using it indoor sessions whilst the weather is bad or you can't go out then it maybe ok. I found even with the real life video that after not very much use i got bored using it that way. If you are planning to use it as a training aid and want to use the power measurement for training by I found that i couldn't get an accurate reading from it. I had a PowerTap and used them together to compare power readings and they were different and my conclusion was that it was the tack training which was less accurate and less consistent as the tyre pressure and heat seemed to effect the readings compared to the PowerTap. This came in the following ways firstly the power values on the imagic were much higher, secondly there was drift upwards in the tacx power values during training sessions and another aspect was that comparitive power values wouldn't be consistent between sessions for example an average power for a session may be 280w on the pt both days but the imagic would be 350 one day and 380 the next . So if you are training by power and use the imagic to set the level you are riding at i found it would actually be way outside my target zone. If you are using it for power training you may want to consider buying a PowerTap or similar highly accurate power meter and a cheap trainer. You can also use the PowerTap on the road

I used my imagic for 3 years, first year I didn't have the PowerTap 2/3rd I did and when I had the PowerTap I could have had any trainer

Anyway just a couple of thoughts

Cheers,

Mark

slunker

Wouldn't be without mine now. save a bit of money and don't buy the steerer, I found it completely useless. Found the turbo great for really poor weather in the winter and allowed me to do 3 hour rides on some RLV. The power is as said not accurate but find that it is consistent when I warm up for 10-15 mins and calibrate the unit, it takes seconds to do. My i-magic is 6 years old and still going strong.

brettjmcc

+1 on the steerer

also, on the warm up, I believe the unit says to do this. One of the guy's in our club has a Cosmos (I think) which is the Fortius motorbrake but without the PC interface. It does the warm up routine for him, he switches it on and it powers itself away. I still have to sit down and see if I can do that on the Fortius

mac220

I'll also add that when I got my powertap I did a bunch of different tests to see if I could get the imagic to be consistent and accurate so I started ensuring tyre pressure was the same(tried different type pressures), following the recommended calibration/trying calbrating at different times during the session, trying different offset values and after having spent quite some time doing these, I'm a bit sad like that, I still found that it was not possible to get the imagic to record consistently compared to the power tap. My reasoning for wanting to get the imagic consistent was that I had an old steal bike that was setup as a turbo trainer bike and I wanted to be able to use it for my turbo sessions to save time getting ready to train and not have to clamp my other bike with the powertap on in the imagic TT and in the winter the powertap would be out on the road for long sunday rides and end up very muddy. I had a turbo specific tyre I wanted to use so I didn't end up wearing out my road tyres more quickly when using them on the TT. I also found that the variation would also depend on the type of session i did for example V02Max training versus Functional threshold training.

Regards,

Mark

neeb

Mark, when you were trying for consistency and comparing to the powertap, were you comparing within a single route, or across different routes?

I have actually just got a powertap, although because the fortius is packed away for the winter I haven't had a chance to check the fortius power values yet. However, what I found was that I could get power values that seemed pretty consistent from one ride to the next, providing 1) I was always comparing a ride on one route to another ride on the same route on a different day 2) I always did the same warmup routine from cold 3) I always checked the tyre pressure etc. when setting up. I'm sure that the power values weren't very accurate, but they seemed fairly consistent from one day to the next on a given route. I never bothered to use the calibrate function, as unless you do it at exactly the same point in the ride/warm-up, it seems to me that it is more likely to introduce another dodgy difficult-to-control variable than it is to iron out day-to-day fluctuations in temperature etc...

My theory is that the main issue with the power readings on the fortius is that they vary a lot according to how warmed up the brake unit is and also the gradient profile. Power values will get higher later in the session and aren't consistent with gradient. But if you always compare the same route with the same warm-up routine, you can pretty much factor that out.

But now I have the powertap I will need to check this when I get the chance...

ajmitchell

hi i have the fortius and powertap and can report that for most out of the box settings the fortius wildly overreports power...i am talking 50% to 100% range. If you have both you can apply the "scaling factor" in the menu to bring them (almost) into line. However i am sorry to report the scaling factor needed is the highest downgrade possible....which is 120 if I recall correctly. This is not a local issue, the same it reports on the taxc forums. Its all a bit depressing when you riding along at 300watts for a month then you realise it was 225w (as happened to me). If i didn't see the 300w I wouldn't have been so sad to see it corrected! We all know how hard it is to gain 50,75,or 100w....now try loosing it! The fortius can be fun esp mountain biking, or velodrome, or short courses in cartoon mode (?virtual) but I am not convienced by the RLV....personally i find them too long (although you can ride any bit you want and scale the gradients down). Manual mode can be useful too as you can create you own workouts. I agree with the post about the steerer though, generally it way way over sensitive and you frustratingly get stuck on kerbs like an idiot!

mac220

I was just looking through my old WKO+ training files to try and find an example of what I found, Ajmitchell above has described exactly what what I got from the imagic. I also fell into the exact same trap, thought I should be signing up for the TDF or Paris Roubaix only to find that it the imagic was out by a 100 watts or so

They aren't consistent with an absolute value, i.e in comparison to a powertap, I know this isn't 100% accurate but it is pretty good and consistent. The power drifts during a session is a serious problem for me. If I'm doing 4 x 20 mins at 240watts with 5 mins recovery between sessions I could find myself significantly outside that target power by the end of the session, which means you are not getting the training effect you are looking for. I found mine would drift quite significantly and this would be enough to change the focus of the session I was doing and when you haven't trained with power to know what these types of sessions should feel like you have no benchmark to measure it against and realise that you are going way to easy.

I guess the point I was trying to put in my post was that if you are looking to do power based training, i.e. using training levels based on power and want to be getting the most out of your training then using a tacx turbo trainer for the power measurement isn't the way to go in my opinion as its not nearly accurate enough and if this is what the opening poster was trying to acheive I wanted to make sure he was aware of this. If this isn't what he was trying to acheive and won't be planning to acheive it then it has no bearing on getting one.

What I did like about it was using the training session application, infact this is what I used exclusively after a while, I would create a training session 4 x 20 mins with warmup, rests and cool down and set the resistance to what I found to reflect the power I needed and it would automatically adjust the resistance for me for each session. Power measurement being performed by the powertap. But it was an expsensive tool to do only that.

Cheers,

Mark

neeb

I was using the fortius almost exclusively with the RLVs, usually with steady hill-climbing routes that would allow me to do threshold efforts or slightly above for 20mins, 40mins or whatever. Rather than knowing what my real threshold power was and aiming for that, I would just get a feel for what a threshold effort represented in terms of average power on a given route as displayed by the fortius by doing all-out efforts. This seemed to work pretty well, although I wasn't really using it to do anything other than near-threshold level efforts for 20 - 40 mins, and I wasn't doing repeat intervals.

Now that I have the powertap, no doubt from my efforts on the road that the power values on the fortius were overestimated, but it's not by such a huge margin as 50%, more like 5 or 10% if I am comparing my average power on an all-out 1 hour steady climb on the fortius to the sort of normalised power figures I am getting from the powertap for a 1 hour effort on the road on rolling terrain. The real test will be running them together indoors however...

Velonutter

Thanks Lads for your input, so where is the cheapest place to get one from?

sedliak

Hi
I've had my Fortius for 3 years now and still use it regularly. I only use it for RLVs ( where the steerer doesn't work). I have no idea about accuracy of power readings on an absolute basis, but I'm pretty sure that if I set tyre pressure and calibrate consistently then the readings are accurate in relative terms. You can use previous efforts as a virtual partner to race yourself up climbs. I'm pretty sure this has had a dramatic effect on my climbing ability. Given the progress I have made against peers and rankings on strava I am a lot faster than I used to be ( and I'm not getting any younger either). I really like the videos as well. Even when I don't feel like pushing myself it is nice to cruise around cape town or Mallorca on a wet winters night

Ps with regard to power readings, a lot of comments above seem to relate to the imagic which has a different motor brake on it to the Fortius. Does this make any difference?

brettjmcc

Sigma are selling Fortius new for £650 (check it comes with TTS3 or 4 though)

There is a used one on eBay here, but needs you to buy the latest TTS (which will cost you about £80 from Tacx): http://www.ebay.co.uk/itm/Tacx-fortius- ... 3a792fee1c

BE CAREFUL - there are more on eBay claiming they are iMagic Fortius. They are not, they are iMagic which has the Flow brake, NOT the magnetic power brake

If you get the Fortius, I have some DVDs I can lend you


OOOOH - Just found this!!! http://www.bike-discount.de/shop/k1008/ ... frame.html

That's probably about £550 with shipping It comes with a Steerer too (you can always sell it for a bit to get some further cash back if you don't want to use it (if you do get a Skyline block riser)

Velonutter

Thanks Brett, much appreciate your help.

brettjmcc

Update: TTS4 is €129!!! So if you get new make sure you get that in the package!

At that price I won't be upgrading any time soon after I shelled out when TTS3 came out. Also, their software is nodelocked (which really pi$$es me off)