Road Cycling - computer is going insane

I've had my computer for about a year now, and recently, it has been going nuts on me. allow me to explain. I'll be going on a perfectly straight, flat road, and it will say something like 19.7mph. it will then proceed to go down to something like 17.3mph and then back to 19.7 in the space of less then a second. the same will happen at other speeds, it will drop a few mph for a fraction of a second, then go back to the original number. could it be a problem with my magnet? I dont think the battery is failing, becuase the screen is still vived and sharp.

Im no expert , but this week weve had sever solar activity . Huge explosions on the sun . The earth magnetic field has been effected . The solar wind speed yesturday was over 700 MPH . Its my oppinion that this solar activity has effected your computer some what . I know a skipper who has had problems with his ships compase . I also now that The so called northern lights may in fact be visable in south eastern USA. Just my two cents . Im no expert though .
jar:)

My computer also has acted up for about a month now, except mine will show me riding 20 mph then drop to 4 mph, or 2 mph it bounces everywhere. I did change the battery but it didnt change anything, I also changed the magnet but I used old magnets so i cant tell if its my computer or the magnet, I even reset the computer as the directions instructed... My computer is wireless and I do check the distance between the magnet and the sensor before each ride.
any info would be appreciated

My computer also has acted up for about a month now, except mine will show me riding 20 mph then drop to 4 mph, or 2 mph it bounces everywhere. I did change the battery but it didnt change anything, I also changed the magnet but I used old magnets so i cant tell if its my computer or the magnet, I even reset the computer as the directions instructed... My computer is wireless and I do check the distance between the magnet and the sensor before each ride.
any info would be appreciated
Hi, mine was wireless too and I go rid of it yesterday, it was a Cateye Cordless7. LBS told me they were all lemons! So they exchanged it for a standard one of my choice and credited me the difference. They said the store was no longer selling cordless ones. Mine did the same thing you described and I did the same things you did and nothing helped. Good luck!

I've had my computer for about a year now, and recently, it has been going nuts on me. allow me to explain. I'll be going on a perfectly straight, flat road, and it will say something like 19.7mph. it will then proceed to go down to something like 17.3mph and then back to 19.7 in the space of less then a second. the same will happen at other speeds, it will drop a few mph for a fraction of a second, then go back to the original number. could it be a problem with my magnet? I dont think the battery is failing, becuase the screen is still vived and sharp.
I bet its a cordless? if it is, get rid of it!

Sounds like a wireless version.

There are usually 2 batteries sin the sender unit and 1 in the receiver.

1 or 2 are probably going. I binned my wireless after about 8 months and
got a 2nd hand wired flightdeck and it has yet to let me down.
My advice - go wired.

it has been my experience that the flucuations in mph reporting is a problem with the computer interface with the click in mount on the handlebar. take an eraser and clean the contacts. mine only happens (wired, not wireless) when either the interface gets dirty (immediate rides after a rain and crud gets in there) OR if it is a cateye, check all the wires that extend down to the magnet sensor. Cateye wires are the thinest and flimsiest in the business (but i still use them)

well, it isn't wireless. its a trek fusion C, wired to the back wheel. I'll try cleaning the contacts, that could be it.

Hi, mine was wireless too and I go rid of it yesterday, it was a Cateye Cordless7. LBS told me they were all lemons! So they exchanged it for a standard one of my choice and credited me the difference. They said the store was no longer selling cordless ones. Mine did the same thing you described and I did the same things you did and nothing helped. Good luck!
Mine is also a cateye7, guess I will scrap it and go with flightdeck..
Thanks for the info

it has been my experience that the flucuations in mph reporting is a problem with the computer interface with the click in mount on the handlebar. take an eraser and clean the contacts. mine only happens (wired, not wireless) when either the interface gets dirty (immediate rides after a rain and crud gets in there) OR if it is a cateye, check all the wires that extend down to the magnet sensor. Cateye wires are the thinest and flimsiest in the business (but i still use them)

That was my hunch also. My computer acts up whenever a little water gets onto the contacts. I have taken to carrying a small plastic bag with me to cover up the computer in case of rain.

Did you check the wheel magnets? If the spacing is marginal, you might be missing a beat when you pedal hard due to flex of wheel and/or frame.

I trashed my wireless cateye and got my new shimano flight deck in and installed today.
Seems like an awsome computer, so far so good :)