Polar CS400 Cyclecomputer

By Joshua Cohen

Like many cyclists, I love to analyze my training data. But I don’t love the time it takes to record everything after a ride — a daily chore that probably discourages many riders from keeping better training logs and using them to progress in the sport.

Enter the new generation of cyclecomputers from Polar. They eliminate the procrastination and excuses by making it easy to record and evaluate the numbers generated by every ride.

Polar is known for its heart rate monitors (HRM). The company has now combined that technology with an advanced cyclecomputer, the CS400. It represents a dramatic overhaul from the CS200 line, having additional features, infra-red data transfer capabilities, and a much more powerful software package to track and analyze training data.

Installation

Easy! The mounting bracket can be put on the stem or handlebar, and then the monitor twists into place. The speed sensor and optional cadence sensor are wireless. Unlike the monitor, neither of the sensors has replaceable batteries. Polar claims they should last for 2,500 hours of riding (about 40,000 miles at 16 mph). Then they can be replaced.

The speed and cadence sensors need to go on opposite sides of the bike to avoid data interference. Setup of the monitor is relatively straightforward and made even quicker with the included ProTrainer 5 software, which makes customizing the CS400 features a snap. You can set wheel size, input personal data, activate reminders, create a training program, set the clock, and much more.

To accomplish data transfer with your home computer it needs to have an infrared (IrDA) port. If it doesn’t (most newer laptops do), you can purchase this $60 Polar IrDA receiver that plugs into a USB port.

This data transfer method is one upgrade from Polar’s CS200 line that really stands out. Those previous models relied on Sonic Link to send data through a microphone to your computer. The IrDA method is much more efficient and reliable. Simply place the CS400 monitor near the IrDA and press the sync button. It works very well.

The chest strap that wirelessly transmits heart rate information to the monitor is flexible and comfortable, as you’d expect given Polar’s years of leadership in the HRM market.

Computer Functions

Unlike the CS600, which costs about $370 more, the CS400 does not include power or some advanced fitness tests. But it still provides a lot of useful training data.

A complete list of the more than 80 cyclecomputer features (not counting the training software features) can be found here. In addition, the CS400 has:

• Customizable data display
• Coded heart rate transmission
• Altimeter with grade percentage
• Thermometer
• Calorie expenditure
• Customizable lap distance recording (so you can analyze data for consecutive laps of a given distance)
• VO2max approximation test (done by measuring heart rate variability while resting; you don’t even need to get on your bike)

The monitor’s display is easy to navigate and has a backlight. Because it can be customized you can decide what is important to you and see it on three lines (plus cadence if you have it). In addition, you can customize up to six different screens (with three data lines on each) and scroll through them while riding. One screen even shows you real-time graphs of accumulating data.

The screen size is adequate for most riding. During intense efforts like time trials, however, I wished I could enlarge specific readouts, such as HR or speed, so I wouldn’t have to think about which line I wanted.

The screen has a clear plastic cover that can sometimes reflect the sun and be difficult to read, especially if the CS400 is mounted on the stem and can’t be tilted forward or backwards. The five buttons (two on each side and one on the front) have a positive click. You can choose to make them beep when pressed.

Data Analysis

If you are laying down $340 for a cyclecomputer, it’s likely you’re interested in all the information it can collect. The monitor can display daily, weekly and longer workout data in clear, easily manageable formats. In order to take full advantage of these numbers over time, Polar includes its ProTrainer 5 software ($75 if purchased separately). Currently, ProTrainer 5 is compatible only with PCs.

ProTrainer 5 lets you quickly download workout data, upload training programs to the monitor, and customize functions. Downloaded data can be displayed graphically over any interval. All you need is to decide what you are looking for.

The calendar is clearly laid out, providing weekly totals and easy access to individual ride data. Customized graphs can quickly be generated. 

The ProTrainer 5 software may be compatible with other Polar HRMs that have downloading capability. Check the Polar website for details.

Bottom Line

Is a cyclecomputer without power measurement really worth $340? Only you can decide. The CS400 packs almost every other feature in a well-made, reliable package that works great alone and really shines when combined with the included training software. The IrDA feature makes data transfer a snap and certainly is a big step up from the Sonic Link used for the CS200.

---

Joshua Cohen is a physical therapist and designer of the Kontact Saddle. He wrote his graduate thesis on male ergonomic bicycle seat design. Then, distilling his voluminous scholarly research, he wrote Finding the Perfect Bicycle Seat and, more recently, The Illustrated Guide to Bicycle Seats. Both eBooks are available in the RBR eBookstore.