I have lost my manual for my 16 function bike computer. where can i get one.

There are a few here, but a model number would narrow it down.

Exertec Exercise Bike User Manuals Download

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Download 1 Exertec Exercise Bike PDF manuals. User manuals, Exertec Exercise Bike Operating guides and Service manuals.

Exertec SP-700 Manuals

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Exertec SP-700 User Manual (18 pages). Training Bike. Brand: Exertec ' Category: Exercise Bike ' Size: 2.07 MB ... Exertec Categories. Fitness Equipment Exercise ...

AirBike-Manual

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Read all instructions in this manual before using the exercise bike. Use the ... For the Air Bike with Stationary Handles, the installation process is almost ...
16 pages

..

the manual covers that, lost that?
Burglar alarm systems is the topic. (loosely related to computers)
"The VISTA-128BPT is a powerful member of the Honeywell Home family of light commercial alarm panels, integrating burglary, CCTV and access control functions."
yes, so is step 1. find the manuals.
2006 made(16 yeas old)
the first manual seen by me (googled) shows it uses real RS232 serial port,that no PC has now.( can be added ask)
pure HONEYWELL product it is. I'd go to their web site.
first hit is here.

https://www.alarmgrid.com/documents/honeywell-4100sm-installion-manual

Manuals are often generic and apply to multiple models. A manual for a simple 16 inch bike is not going to have much in it.

I’m happy to help further over the phone at https://www.6ya.com/expert/donald_f2ed37026a3ac881

Hi moparman2676...
I could not find a Schwinn 13 function wireless bike computer user manual, but I did find a Schwinn 12 function wireless bike computer user manual at this webpage:
Please take time to rate me thumbs up

http://www.k3pgp.org/schwinnmanual.htm

Simple search engines find things like this faster than waiting for Fixya experts to respond.

"sigma 506 manual"

Manuafacturers usually have the manuals. sigmasports.

http://www.sigmasport.com/en/service_center/produkt_support/bikecomputer/fragen/?jahrgang=4&produkt=67&gruppe=1&sprache=2&typ=bikecomputer

See the page (16 of 50) where they talk about selecting MPH or KPH. It's prompting you to confirm a choice.

26 inch wheel becomes 29 inches when you add on tyre depth ( 1.5 * 2 )
29 x Pi is 91 inches
Computer setting should be 91.2 inch or 2316 mm

http://www.vetta.com/Tech%20Support/DP/C20.eng.pdf

Manual is online here. See page 16 for linking instructions