Cateye OS 1.0

By John Stevenson, December 20, 2001

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Cateye OS 1.0
Photo: © Cyclingnews

Cateye's OS 1.0 is the most customisable computer I've ever used, and has the largest range of functions into the bargain. Its basic function set is pretty straightforward: speed, maximum speed, average speed, distance, odometer, clock. What sets it apart is that you can choose which of those functions you have access to. You can also change the size of the display characters; you can get a total and a graphical display of your riding for the previous day, week, month, and year; you can switch between two wheel sizes for road and MTB use; you can choose from two modes for measuring average speed; and more.

All this information comes at you through a large LCD dot-matrix display. This is what gives the OS 1.0 its versatility – the large screen enables a dual display with large characters, and makes possible the bar graphs for your recent riding. The display also includes indicator icons for battery life, tyre size, auto-start, and pace arrows to show that you're over or above your average speed.

It sounds bewildering, but Cateye has done a good job of making it easy to navigate, though the notion that you don't need the manual to set it up is a bit optimistic. But in combination with the clear, well-written manual, it's straightforward enough. You can use its pre-sets for your wheel size or enter an exact figure, and you can transfer your existing distance from another computer during the set-up operation.

Once it's set up, two large buttons on the near edge of the computer switch between the functions and the 'mode navigation' feature shows you which function you're switching to. The start/stop button does exactly that if you're not in 'auto' mode and the menu button under the display accesses the data review and set-up functions like weekly, and monthly distance totals and graphs.

On the road – and the trail

It's very easy to switch between functions as you ride, and I've even managed to memorise the key combination that zeroes the stopwatch and trip meter. I won't mention the maker of last computer I used, but it seemed to need an arcane combination of mode, keypress, wind direction and phase of the moon to zero the trip distance. In six months of use I managed to find it without the manual exactly twice. The OS 1.0's combination of mode and start/stop keys is far easier.

The large display is easy to read, and as I switch between road and MTBs a lot I'm finding the dual tyre size function is very useful indeed. Also high on my favourite list is the 'max speed ever' feature which will be great for bragging rights after the next time I throw myself down a decent sized hill… or may just serve to permanently remind me what a wuss I am.

A warning for compulsive fidgeters: messing about with the date and time can zero the accumulated data. I just wiped the details (thought not the odometer total) of all the riding I've done with the OS 1.0 by paging through the 'set the date' menu and changing the date, then changing it back.

The ability to switch between automatic and manual modes for the measurement of time, distance and average speed is also pretty useful, though it's not unique to the OS 1.0 – most Cateye computers have this feature. In manual mode the average speed takes into account stops, which can be useful for 'rest of the ride' planning, while in auto mode the time and average is only measured when you're actually moving.

If there's a racing certainty with a computer that has this many functions, it's that sooner or later you're going to need the manual to help you make an adjustment. By then, the compact 'reference guide' booklet Cateye supplies will be long lost. Fortunately, like RockShox and a few other web-savvy manufacturers, Cateye has put the manual on its website as an Acrobat (.pdf) file so you can easily get a replacement.

The only problem I've encountered is that the display sometimes shows vertical streaks when there are lots of vertical bars in the characters displayed. If I wanted to be grumpy I could wonder if anyone really needs all this information as they ride, but I'm finding having it to hand is really quite amusing so it works for me.


The OS 1.0 is a data-junkie's dream. The only way to get more data about your riding is to invest in one of the heart rate monitors that include PC download capabilities, but then you're talking lots more dollars. That said, a function I'd like to see is the ability to set a target time and distance and have the computer tell you what speed you need to do to hit the goal.

Price guide: US$80
Lots of functions, dual wheel size, easy to set up, data review features, customisable
Con: Streaky display
More information: Cateye's website
Cyclingnews Rating: Click for key to ratings

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