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Sigma Rox 9.0 – Part II

This post is the second (and probably more interesting/useful!) post about my new Sigma ROX 9.0 cycling computer.  It’s  following up on the post I made about my Initial Impressions of the unit.  All of my comments in that post still hold; I’m still very impressed with the unit.


I bought the Sigma ROX 9.0 after quite a bit of online research.  I was looking for a computer that had ‘normal’ cycling functions (speed, time, distance, etc.) as well as heart rate.  I didn’t need/couldn’t afford GPS, so that ruled out the (very nice) Garmin units.  I say “very nice” based on specs/functions, but the Garmins do have their own share of issues if you can believe the reviews.   Since I can’t even begin to afford any of the options with power, we won’t even bother talking about that!  Maybe one day…

After reading every review I could get my hands on for a whole bunch of units, I was not very confident in the Cateye V3, even though it fit my specs and I have been happy with the low-end Cateye units I’ve had in the past.  I also took a long look at the Blackburn Neuro line, but they had very few reviews online, and unfortunately the majority of them  suggested some issues (albeit small ones).  However, the Sigma had a fair number of reviews (not nearly as many as the more mainstream Cateye or Garmin units though) and not one had a bad thing to say!  A few suggested some minor issues (as will the review you’re reading now) but nothing that I considered to be serious or a show stopper.   It also helps that the Rox has a website where you can demo the unit and check out all the functions.  I highly recommend doing so if you are interested in buying one by clicking here.  I was also able to get a good deal on the unit, which sealed it for me!


After my initial impressions, the next big task was installing the unit.  This went quite smoothly since it’s a full wireless unit.  The sticky pad on the mount (mounts equally well on stem or bars by the way) is tenacious, so if you position it wrong, it will tear when you pull it off to reposition. I learned that the hard way!  However, I was planning on using zip-ties anyway, so I was not too concerned.  Essentially, each transmitter is positioned to be within the minimum distance of the magnet, and fastened either via rubber ‘o-ring’ or zip-tie.  I’ve zip-tied the computer mount and cadence magnet, but at this point I’m running the speed and cadence transmitters with the rubber o-rings.  Once I’m confident they are in the right spot, I will zip tie those as well.  The first minor issue with the unit cropped up here.  The quality of the zip-ties supplied with the unit is low! I snapped several trying to get them tight, and did not snap one of my own (after I ran out of the ones supplied with the unit…)  Make sure to have several spares in waiting as you mount things.

The spoke magnet is larger than most I’ve seen, but doesn’t seem to be a problem.  The two sensors/transmitters are fairly large as well, but once mounted, they’re relatively inconspicuous.  Essentially, everything just worked.  The clearance between the cadence magnet and cadence sensor/transmitter has to be pretty tight in order for it to pick up, but once I got it set, it hasn’t failed since!

On my (relatively short) stem, the computer fills almost the entire stem.  Make sure to mount it far enough from the bottom that you can still press the buttons.  Mine is perhaps a bit tight, but good enough for now!

Software Install:

The unit comes with software on a DVD.  However, you can also download it from the Sigma website. I initially installed via the disc, but it asked me to upgrade from the website, so I could have just done that to begin with!  It’s a painless install (Adobe Air based) and works on Windows only (a problem for a few I’m sure, but not for me.)

Computer Setup:

All settings on the computer can be made via the “Settings” menu on the unit itself.  However, you can also snap it into the USB cradle and set it via the PC software, which is a bit easier.  It also lets you save the settings files for future reference.

On-Road Impressions:

After a couple of rides with the unit, I’m very impressed.  It’s well thought out in terms of on-bike use, and the display is easy to manage and customize.  The top row will show elevation, inclination, heart rate and cadence, either all four at once, or one at a time in a much larger font.  I find that all four at once is great, and (unless you’re going really hard) still quite legible while riding.

The large middle display section displays your speed and misc. icons.  Really, while riding speed is all you care about here.

The bottom portion of the display can be customized to page through almost any of the other values possible.  The unit comes pre-set with 2 different options (Favourites A and B) and I have yet to change them, although I suspect I will pare down “Favourites A” to only show 3 or 4 things so I don’t have to page through things like the stopwatch and countdown timer all the time.  These are nice to have, but won’t get used that much!

While riding, there’s a noticeable ‘lag’ in the change in values, which is a bit annoying.  For some reason my low-end Cateye was virtually instant in this respect, so it’s a bit disappointing.  However, the Cateye was a wired unit, and recording only one value (speed) not multiple, so I’ll give the Sigma a pass here.  I believe other wireless units have similar problems.  In the end this is a minor problem, and I suspect it will be pretty easy to get used to.

The unit will record a ‘log’ or a ‘ride’ – essentially, if you do nothing (just snap the unit in and start riding) it will record a ‘ride.’  It’ll store standard values for 7 rides, stamping them each with a date and time.  This is very nice.  However, if you know you will want to graph and analyze the ride later on, you can also start a ‘log’ manually.  This allows you to create graphs in the PC software post-ride.  So far I’ve been doing both; why not?!

You can set a ‘waypoint’ by pressing the main ‘middle button’ on the unit. Note that because this is not a GPS unit, it’s not recording coordinates of a place on Earth; it’s just marking that particular moment in time as a ‘point of interest’ so you can easily identify it on the graph later for analysis.  In the example graph below, you’ll see I set several, (the vertical lines on the graph) including one at the bottom and top of the climb in order to analyze that section separately when I got home.  This would also be great for a ‘lapped’ race, where you could set a waypoint each time you begin a new lap, and thus analyze each lap independently post-race.

If you turn on the audible alarms, the unit will beep at you when you change heart rate zones.  Three short, quick beeps means you’re below your Zone 1 setting.  These three short beeps will repeat every 20 seconds until you enter Zone 1.  If you are purposefully riding below Zone 1, this can be annoying.  Luckily you can turn the volume down, or turn off the audible alarm all-together.  When you enter Zone 1, you get a long single beep; Zone 2, two long beeps, and three long beeps alert you that you are entering Zone 3.  Makes sense!

Post-ride PC Analysis:

After your ride, you can manually stop the log (if you started one) and reset/save the trip values.  By snapping the unit into the USB unit, you can quickly download the data to the PC and clear the memory on the unit.  If you just rode without manually starting a ‘log,’ you will get basic totals and average values for the ride, as below (all example data/graphs are from my Attack on Foley Mountain ride…ignore the Heart Rate Zone info as I didn’t have it set properly at the time):

Sigma Data Center Memory Screen

Sigma Data Center "Memory" Screen

If you manually started a ‘log’ at the beginning of the ride, you can get all the fun graphs that look like this:

Sigma Data Center Graph

Sigma Data Center Graph

The nice thing about the graph is that you can very quickly and easily recalculate average values for any portion of the ride by sliding the ‘start’ and ‘end’ lines.  The values automatically change as you slide.  This is great to analyze the climb only, or the headwind portion of a ride separately from the tailwind portion, for example.

Things I would change:

So yes, the unit just works, and does it quite well! However, nothing is perfect, and there are a few things I would like to change about it.  In no particular order:

  • Why only three heart rate zones?  I would love to see five zones like most of the serious heart-rate monitors available.
  • Get rid of the ‘lag’ in speed/cadence/heart rate pickup.  This may be impossible on a wireless unit, but my cheap-o Cateye wired unit was better, so it’s a bit disappointing!
  • Better quality/more zip ties included in the package please!  This is not a place to save 14 cents.
  • The ‘log’ feature doesn’t save cadence.  The manual says this is due to ‘memory limitations.’  B.S.!  The log lets you set logging intervals, and at a 5 second interval there’s enough memory for ~13 hours of logging.  How about record 1 more number for cadence, and record only 9 hours of data?  How often do we ride more than 13 hours?
  • Similar to the above, give us a ‘1 second’ recording interval.  If I can record at a five second interval for ~13 hours, how about at a 1 second interval for 2.5?  For shorter rides, this would be great.  Since the user can control the interval, if you knew you were going on a longer ride, you could change the interval.  Even better, how about record at a 1 second interval until the memory is full, then ‘intelligently drop’ every other value, or values with the least ‘change’ surrounding them, once the memory fills up?
  • I noticed a weird bug on the graph where the vertical lines representing ‘waypoints’ and ‘pauses’ on the graph were not moving as I zoomed in/out or moved across the graph.  However, I cannot reproduce the problem and it’s worked every time since, so it’s a pretty minor issue!
  • …not much else.  At this point I really wouldn’t change much else!  I’m sure I’ll find a few other little nit-picky things as I use the unit more, but I can’t foresee any showstoppers at this point.

Overall, I’m quite happy with the unit, and hope it lasts me a long long time.  I’ll be ordering a second-bike kit to mount it on the new TT bike.


Pingback from DARREN COPE » Sigma Rox 9.0 – Initial Impressions
Time March 21, 2010 at 5:31 pm

[…] Edit: See my more in-depth review here. […]

Comment from Jose Martins
Time August 17, 2010 at 5:34 am

I have Sigma ROX 9.0 since 1st December 2008. I’m logging every ride from home to work.
I would like to had something in your review on thing that de device could/should have.

– There should be an option to log every time you start ridding. ( sometimes I grab the bike and notice after a while that I forgot to mannualy start the logging)

– In sigma Data Center, every time I switch from log to log, it takes a long time to read the 260 log files I have so far. Perhaps Un upgrade of the software should fix this one.

I very much agree with you about the lack of logging on the cadence… this is perhaps the major fault of the device. Why showing it on the ride and not on the graphic log chart…

Great review,
Jose Martins

Comment from Darren
Time August 18, 2010 at 8:17 pm


Thanks for the comments! You are right that the logs are slow to load in Sigma Data Centre. Also, I see no way of exporting the logs from there, which seems like a bit of an oversight! Hopefully new versions of the software are released that fix these issues!

The option to log rides automatically would also be nice–another thing to add to the wish list!

Thanks for your comments!

Pingback from DARREN COPE » Sigma Rox 9.0 Follow-up Review – One Year In
Time May 3, 2011 at 8:15 pm

[…] now been using my Sigma Rox 9.0 for over a year. My previous posts (Initial Impressions, and Sigma Rox 9.0 – Part II) have been getting a fair amount of traffic, so I thought it a good idea to provide a detailed […]

Comment from Brooks More
Time September 7, 2011 at 11:22 am

Hi Darren,

Does the Rox 9.0 have a lap feature? For example, if I am performing intervals, can I start and stop an interval timer that records data for each interval (such as average/max speed, average heart rate and time in each zone, averge/max cadence)?

Thanks for your time and assistance.


Comment from darrencope
Time September 7, 2011 at 1:17 pm

Hi John,

There’s no specific ‘lap’ feature; however, you can use the ‘waypoint’ functionality to simulate it. In other words, record a waypoint at the end of every lap. Then when you download the file to the computer, you can drag the ‘segments’ to show only the section you are interested in and it will calculate averages, etc. for just that segment. Not ideal, but it does work :)

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