Reports of the demise of this Web site are greatly exaggerated! We at sheldonbrown.com thank Harris Cyclery for its support over the years. Harris Cyclery has closed, but we keep going. Keep visiting the site for new and updated articles, and news about possible new affilations.
Additional Cyclecomputer Calibration Procedures - Ciclomaster to Trek
Our cyclecomputer database is your starting point when looking for information on cyclecomputers. It links to owner's manuals for most cyclecomputers. Sometimes we had to work without a manual, or have additional information. That information is on this page if the brand name begins with C through T, except for Cateye, which got its own page.
Look for similarities in appearance and function when trying instructions for a computer not on our list. Many bicycle computers are rebranded. Please let us know of rebranded models which you have identified.
Old versions of manufacturers' Web sites preserved on the Internet Archive may list older models. A Web search on the make and model, plus "manual" or "instructions" sometimes turns up information posted by an owner. If you have information on a model not covered here, please send it in.
Ciclomaster computers have an unusual feature. They incorporate a small capacitor to maintain short-term memory while the battery is being changed, so if you are reasonably quick about it you can change the battery without losing the calibration, and even maintain the stored odometer mileage.
Entering "Set" mode:
Press and hold both "SET" and "MODE" buttoms for 5 seconds.
Use "SET" button to select miles or kilometers.
Then press "MODE"
Changing setting:
Set calibration with "SET" key
Exiting "Set" mode:
Press "MODE".
If altitude module included, press "SET" again with bike on level surface to calibrate altimeter.
If you change the battery in less than 30 seconds, you can save your data.
This unit uses the wheel diameter in mm for a calibration number for km.
This number times .621 is used for mile readings.
Use
chart D, but multiply the value listed by 2 for km, or by 1.242 for miles.
Press and hold both buttons simultaneously, until all Eights are displayed to reset computer.
Display then…hopefully???…. indicates wheel size automatically.
Right button adjusts digits. Left button sets selection.
Changing setting:
KM/Miles. Right to change. Left, sets selection.
Run through all the remaining functions using Mode and Set.
To set 12/24 hour, and time. Hold down left button when time is displayed.
Right button to change 12/24 then, left, set.
Repeat for time.
Temperature, when displayed. Hold set. Change with right button, C-F. Then set.
Rhode Gear Quantum
Calibration: no info.
Probably can be figured out from what appears on the display.
Battery: Size "J" rectangular.
(This is a rare battery, you may be able to find it in a camera shop, it was used in some older pocket cameras.)
This computer is integrated with special Shimano brake/shift levers with control buttons and so it shows the gear in use -- a clever idea with problems in execution: for one thing, the computer only works with those levers. For another, it is posssible unintentionally to delete trip data by pressing the on-off button on the left brake hood. This problem can be addressed by placing a washer around the button so it can't be pressed accidentally. Then it is necessary to peel back the rubber hood and depress the button with a pen tip or the like.
Press and hold B button (bottom of unit) for 5 seconds
Changing setting:
Press button A to select mile/h or km/h
Press button B to accept selection and go on to wheel calibration
Repeat sequence to set, in turn:
Wheel calibration number
Chainwheel sizes, largest first
Note, active value will be flashing at the lower left side of the speed. After the first chainwheel has been set, and you move on to the second, the previous selected chainwheel size will be displayed on the right side for reference.
Rear sprocket sizes, smallest first
Once all sprocket sizes have been set, press and hold button B for 5 seconds.
Select "111" for standard rear derailer, or "222" for "Rapid Rise" (reverse action) rear derailer.
Here is one style of cyclecomputer which is sold under so many brand names that we quit trying to list them all. They are rebranded Sunding. If color schemes are consistent, they are:
SD-548C if wireless (gray border around display, as shown)
In any mode EXCEPT clock mode, press and hold both buttons for about 4 seconds, or until the M/h or Km/h symbol appears.
Changing setting:
Press LEFT button until desired units (M/h or Km/h) are selected.
Press RIGHT button to accept. Current calibration number will appear, with one digit flashing.
Press LEFT button to change the flashing digit, press RIGHT button to accept flashing digit and go to next digit.
After the 4th digit has been selected, pressing the RIGHT button will take you to the settable odometer screen, where you can use the same procedure to restore mileage values lost during battery change.
Exiting "Set" mode:
Press and hold the right button for 5 seconds if you wish to bypass the settable odometer stage.
Clock setting:
In clock mode, press and hold both buttons for about 4 seconds, or until a flashing 12 or 24 appears. (There will be no mode icon for "clock," but you will see hours and minutes with a flashing colon.
Press LEFT button until desired mode (12 hour/24 hour) is selected.
Press RIGHT button to accept. Current time setting will appear, with hours flashing.
Press LEFT button to change the hour, press RIGHT button to accept and go to minutes.
Reports of the demise of this Web site are greatly exaggerated! We at sheldonbrown.com thank Harris Cyclery for its support over the years. Harris Cyclery has closed, but we keep going. Keep visiting the site for new and updated articles, and news about possible new affilations.
