Rally Sport / Rally cycle computer – umsc03schwe1# – for Schwinn bicycles – manual


Rally Sport / Rally cycle computer – umsc03schwe1# – for Schwinn bicycles

LR44 battery, alkaline 1.5 volt button cell, now replaced by 357/303 or just 357 battery.

The display on the screen of the cycle computer was getting dim, and I couldn’t find the manual that came with it until today.  I was able to putz around with the single button that is found on the back of the unit before finding the manual.  But I figure that other people might have the same cycle computer and not know how to re-set everything after replacing the button cell battery.

The battery used to go by “LR44”, I think that is the alkaline version, and that the silver-oxide version is “357” or “357/303”.




The “c” is for the circumference of the bicycle in millimeters. You take the diameter of the bicycle tire, mine is 26 inches. Convert to millimeters, that brings us to 660.4

Then multiply by 3.1416 to get the circumference. Circumference = pi times diameter.

THAT is what you have to enter after the “c”. You can also set the time, choose between km/h and mph, etc.


About johnvkaravitis

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6 Responses to Rally Sport / Rally cycle computer – umsc03schwe1# – for Schwinn bicycles – manual

  1. John says:

    Wild. I just bought a replacement battery this afternoon (a 357). My display was getting dim too, and I hoped it was just the battery. The display is nice and dark now. Unfortunately it reset itself, and I can’t find MY manual either.

    Here’s my best guess:
    If it’s not flashing Km/h, but showing 0:00, then you need to reset it. Pull out the battery, wait a couple of minutes and put it back in, or just hold down the button while you put the battery in. Release the button. You should see all the display marching its numbers. Now press and hold the button until the marching stops.

    The first thing to set is metric or English. Push once to change, push and hold to choose, just like you normally use the button.
    The next setting is called “c”. I believe it is the diameter of your tire (since it only goes into the 30s when I’ve selected English units). Carefully put in your tire size (26.00 for me). If you mess it up, continue on through the digits — you can come back and do them again.

    When you’ve got that set, just leave it alone. After a minute or two the unit will display 0.0 m/h, dst 0.00. Snap it onto your bike and go!

    Now I’ve got to go for a spin and make sure the speed approximately matches the gps on my phone so I know I didn’t totally screw-up the ‘c’ setting….

  2. Pat says:

    Thanks so much for posting the .pdf. Mine sat unused for years in the garage and I just brought it back to life with a new battery and your help.

    • You’re welcome. If it still works, why bother buying a replacement?

      And thanks for your post, it will actually make me get off my butt this weekend and go for my first bike ride of the year.


      John V. Karavitis

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