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  • Digital wireless technology eliminates messy wires
  • 4-line MacroMonitor™ LCD displays up to 5 pieces of data at a glance
  • 9 functions include speed comparator, speed, average speed, maximum speed, ride time, distance, clock, dual odometer and temperature
  • Fits 25.0-31.8mm handlebars
  • Magnet fits up to 4mm bladed spokes


View all Planet Bike Cycling Computers

REI membership


Best Use Cycling
Current Speed Yes
Maximum Speed Yes
Average Speed Yes
Speed Comparator Yes
Odometer Yes
Trip Distance Yes
Auto Start/Stop Yes
Clock Yes
Dual Bike Memory Yes
Altimeter No
Temperature Yes
Batteries 3V CR2032
Wireless Yes
Rated 1 out of 5 by from Disappointing I'm a fan of Planet Bike, and this item is a disappointment. This unit has a great display, which is what probably attracts most people. However, the wheel motion sensing transmitter is very poorly engineered: 1. The sensor and magnet must be aligned at less than 2mm accuracy. 2. The battery compartment projects into the spoke sweep space, making the 2mm hard to achieve without the spokes striking the battery compartment. 3. The sensor mounting system has more than 2mm of wobble, which makes keeping the unit aligned difficult. I spent more than an hour trying to get this computer working and never did get a valid mph reading. I'm returning it.
Date published: 2011-05-22
Rated 1 out of 5 by from Doesn't work properly.. I bought this computer because I liked the simplicity and large display. Unfortunately, the computer can't recieve the information from the sensor unless it's within a foot from it, and the sensor is as close from rubbing aganist the magnet as it possibly can be. Also, the mounting for the sensor is just two zip ties, and with normal use these don't hold up the sensor for very long, in which case the whole thing ends up getting smacked by my spokes and flies off from my bike. Seems like a probably got a bad egg as far as the readout is concerned, but the mounting for the sensor is just a really bad design in my opinion.
Date published: 2012-04-03
Rated 3 out of 5 by from REI Gets 1 Star, The Protege Gets 3 Stars REI claims this computer has Auto Start/Stop. That is false. The wireless version does not Auto Start, you have to manually push on the unit to get the display going. Nothing on the box or in the instructions claims Auto Start. REI - please change your online listing to remove Auto Start. The unit does have Auto Stop. So if during a ride you have a long wait at a traffic light or maybe stop to blow your nose, the display shuts off in 2 minutes (120 seconds). If you don't notice and manually restart it.............darn! Otherwise the wireless version has a nice sized display and is no harder to program than any other cycle computer. The wired version does have Auto Start/Stop.
Date published: 2015-11-19
Rated 4 out of 5 by from Great Computer This computer performs as advertised. The large display with plenty of information on one screen is really convenient. Unlike other reviewers, I found the directions and set-up fairly easy. Took me about 15 minutes to install and set computer. Aligning the sensor with the magnet was a little tricky- the magnet has to be really close. READ THE DIRECTION CARELFULLY and follow the set-up order. I have no problem with auto-start. I was told that some users have problems with the radio not responding because they live or ride near heavy radio traffic or power lines. I live in Fullerton California and have had no problems.
Date published: 2009-09-11
Rated 2 out of 5 by from Maximum speed erroneous. The computer mounted easily, has a nice tidy look without wires and shows everything I want to see while riding. It lacks accuracy, especially the maximum speed feature. It read 93 mph, 53 mph, speeds which I have never attained. My typical maximum speed is around 30 mph. The odometer seemed erratic, starting out it read high, i.e. 5.06 at the 5.0 mile mark, yet read low at the end of the ride, i.e. 25.33 at 25.44 miles. I know my route check points. I suspect the wireless feature may be the culprit. I exchanged it for the wired version at REI and so far it is working well.
Date published: 2014-01-23
Rated 3 out of 5 by from Good Unit Minor Issue Just purchased this unit and all in all pretty happy with minor exception. I noticed a black dot with ghosting on the units lens. I took it back to REI and tried to determine if it was a defect or not. The short story is if you wear polarized glasses when you ride you will see a black dot on the lens, and according to the manufacturer, Planet Bike, this is due to a "double Polarization" effect from looking at the lens with polarized glasses. It is however more than just a dot as it shows ghosting across the screen. According to the manufacturer the only work around is to not wear polarized glasses.
Date published: 2009-11-11
Rated 2 out of 5 by from Hard to love. I recently switched to a 29er and this computer was INCREDIBLY difficult to program. It requires taking multiple measurements, calculating average wheel base coverage, and multiple manual inputs on a basic click-through interface. After all that it is only roughly accurate for speed and distance. I checked it against a GPS unit several times and it was off by about 3/4 of a mile after about 14 miles. The display is nice and large. Makes reading while riding tough terrain easy. I intend to return it and find one preprogrammed for my size bike. As usual the customer service at REI was fantastic.
Date published: 2013-05-21
Rated 1 out of 5 by from Not Accurate at all I bought these (bought two) largely due to the high ratings it received here, but my experience with it has been disappointing. First and foremost the readings gotta be accurate and this computer is not even close. On a century ride (103 actual miles), it registered only 93 miles. On other rides with specified mileage, it's been off by about 5% (over and under). I assume that this kind of misreading will also affect AVG speed and other calculations. The temperature reading is often off by more than 10 degrees. Lastly, the screen has developed a dark spot (on both) which makes it difficult to read the current speed.
Date published: 2010-02-21
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Does the Planet Bike Protege 9.0 wireless work with ANT+ sensors?   

Asked by: Skywalker56
The Protege 9.0 will not work with ANT+ sensors.
Answered by: REIservice
Date published: 2015-09-20

Are the units in metric? Distance in kilometers,speed in kilometers/hour?

Asked by: roymcshine
Yes. The units are switchable between metric and U.S. units.
Answered by: REIservice
Date published: 2015-09-20
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