Sigma 2006 MHR - do not buy try pretty hard to stay positive and only post negative posts about epic fails like Race Face's sucky product failures and sucky customer service. But I'm afraid I have to post a negative post about the Sigma BC 2006 MHR bike computer. I got one because Erin had one and she loved it and it had all the features I wanted and then some. I'd had trouble with wired bike computers in the past, seems the connectors on the mount just end up getting dirty. Using a pencil eraser on them, or contact cleaner would sometimes help but eventually the problem came back. My trusty Specialized Team Wireless bike computer was pretty awesome, as long as I remembered to push a button to make it start looking at the start of a ride. It also showed the time all the time which I really liked. But I was missing altitude and also temperature which is some data I really wanted to start collecting. The Sigma bc2006mhr had it all and I installed it right away.

Before I get into some of the details of this bike computer I'll outline the one flaw that makes me want to yell and scream and insist that you not buy it. The computer will easily get itself into a state where it looks normal but will not register the wheel rotating. You might not notice this and lose a lot of riding data. What's worse is that the only way to get it to look foryour wheel again is to take it out of the mount for 10 seconds and put it back in (or press and hold a bunch of buttons for a 30 second process). This is inexcusable, dangerous and incredibly frustrating. If you're looking for similar functionality I've had great luck with a VDO MC1.0 wired bike computer. A review of that is coming up soon.

How does the sigma lock up? It has a bump sensor which is slick, if the bike is moved it starts looking for a wheel and counting distance. This is a really awesome idea with an awful implementaion. If it doesn't find a wheel in 2 minutes it gives up (to save on battery life). However the unit needs 5 minutes of no bumping to go to sleep properly. during the 3 minutes between when it stops looking and the 5 minutes to sleep, if you bump it, it stays in this state of retardedness where it's not looking for anything. The only way to make it look again is to take it out of the mount or go into settings menu and then out of settings menu. This is dangerous when you're riding down the trail.

You might think that's not a big deal, you might imagine that you rarely enter this limbo time period during normal riding, but I hit it so often that it drove me crazy. My bike on the roof of the car would put it into this stuck state. Stopping on a trail and chatting with my friends would cause it to lock up.

I worked with Sigma support on this for 6 weeks, they sent me a new (refurbished) unit which had the same problems (and a nearly flat battery when the one I sent them was with a brand new battery!). In the end they said this is how it's designed to be and that I should just try and sell it. They were in a tough spot since I hadn't bought it from them, so they couldn't offer me my money back. They did offer me a generous credit towards other sigma products but I was pretty soured on them by this and just wanted my money back. In the end I mailed the used unit (with no box) back to Bike Nashbar and they were awesome and gave me my money back. I'd already ordered a replacement unit, the VDO MC1.0 which has been working great.

Here's some other complaints I have about the unit:
  • The mount has contacts on it even though the unit is wireless. This has me worried that if the contacts on the bottom of the mount start getting flaky will the computer just stop working. All the drawbacks of wireless and a wired computer.
  • Resetting trip takes a long time. You have to hold the button until it resets just the distance (or whatever's showing) and then wait until it resets all and then stops flashing. Takes quite a while, especially if you're riding along the trail at the time.
  • It has 4 buttons, but only 2 really move between the data you want to see, which means to get to trip altitude or the temperature it's 4 or so presses of the button.
  • The heart rate monitor display is always there, even if you have it turned off. If the hear rate monitor is of, why not use those digits to show the current time or something useful. or just blank, rather than a distracting OFF.
There were a few things I liked about it, until it let me down so badly.
  • Really nice settings. It was really easy to setup. Sometimes the use of buttons wasn't quite uniform, sometimes the bottom right button would toggle an option, other times it would move between digits, but generally it was easy to do.
  • Nice clear display. The display was big and very easy to read. The backlight was good with a full battery but often using the backlight would cause the display to show zero
  • With a second wheel kit you can seamlessly move between bikes, just move the head unit and you're done. The second wheel kits transmits that it's the 2nd bike and everything just works. No need to remember to switch between wheel sizes.
None of thse benefits outweigh the fact it might just lock up on you and stop recording your trip info.