cycle comp driving me bonkers
#1
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
cycle comp driving me bonkers
My cyclocomputer (odometer) has recentlystarted to measure double the speed. I have no idea why it's happening, except I *think* it's happening when the temp goes over 12 or so degrees C. I tried disengaging it from the cradle, resetting it, and a number of combinations of the above.
Then, after a while, it would work OK again.
This erratic behaviour started now at the beginning of spring. I cycled most of the winter with this cycle comp.
I also tried adjusting the magnet on the spoke a few mm lower, or to the side, but it had absolutely no effect.
Any idea? The cyclecomp is branded "Union 10", if that's of any help.
Then, after a while, it would work OK again.
This erratic behaviour started now at the beginning of spring. I cycled most of the winter with this cycle comp.
I also tried adjusting the magnet on the spoke a few mm lower, or to the side, but it had absolutely no effect.
Any idea? The cyclecomp is branded "Union 10", if that's of any help.
#2
Perineal Pressurized
Join Date: Oct 2003
Location: In Ebritated
Posts: 6,555
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
New battery?
__________________
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
#3
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by dobber
New battery?
Still, I don't completely rule out the battery theory, just think it's quite unlikely.
#4
Senior Member
Join Date: Apr 2005
Location: Minneapolis, MN, USA
Posts: 1,152
Bikes: 1990 Burley Bossa Nova, 1992 Paramount PDG-70, 1993 Specialized Stumpjumper, 2005 Jamis Dakar XC Pro, 2007 Rivendell Bleriot
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Likes: 0
Liked 5 Times
in
3 Posts
Nearly all cyclocomputers (with the exception of some early Avocet models IIRC) work with a reed switch which gets activated by the magnet..
sounds like your reed switch might be wonky, perhaps with a bad connection that gives an intermittent signal which the computer is interpreting as multiple circuit closures for every 'real' triggering of the switch.
Perhaps you should try a new harness and sensor.
EDIT: nevermind, read your second post... hmm.. is your wheel diameter set correctly on that computer?
sounds like your reed switch might be wonky, perhaps with a bad connection that gives an intermittent signal which the computer is interpreting as multiple circuit closures for every 'real' triggering of the switch.
Perhaps you should try a new harness and sensor.
EDIT: nevermind, read your second post... hmm.. is your wheel diameter set correctly on that computer?
#5
Member
Join Date: Sep 2004
Posts: 30
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
magnetic field sometimes passes the sensor 2 times on each rotation of the wheel, try moving the magnet close, farther away or up or down the spoke.
also if the magnet and sensor are to low on the fork this effect will be worse because the magnet is moving slower.
also if the magnet and sensor are to low on the fork this effect will be worse because the magnet is moving slower.
#6
Senior Member
Join Date: Nov 2006
Location: slow-mo peloton of one
Posts: 159
Bikes: Klein Quantum, Summit Comp Pro TR
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Originally Posted by neutron7
also if the magnet and sensor are to low on the fork this effect will be worse because the magnet is moving slower.
#7
2-Cyl, 1/2 HP @ 90 RPM
Join Date: Oct 2003
Location: NYC
Posts: 15,762
Bikes: 04' Specialized Hardrock Sport, 03' Giant OCR2 (SOLD!), 04' Litespeed Firenze, 04' Giant OCR Touring, 07' Specialized Langster Comp
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 4 Times
in
4 Posts
If the magnet's orientation is N-S or vice versa parallel to the line of rotation, then the N and S will trigger the reed each time it passes, leading to 2 activations per pass whereas if N-S is perpendicular, then it's once.
#8
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
To all you guys who were thinking aloud about magnetic fields and reed relays; thanks for the effort, but as I sadi, as part of the debugging process I swapped out the cyclocomp (I have an identical one on the MTB), and that worked fine. So it's not the "aquisition/sensor" part of the system that is broken.
#9
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by robo
Nearly all cyclocomputers (with the exception of some early Avocet models IIRC) work with a reed switch which gets activated by the magnet..
sounds like your reed switch might be wonky, perhaps with a bad connection that gives an intermittent signal which the computer is interpreting as multiple circuit closures for every 'real' triggering of the switch.
Perhaps you should try a new harness and sensor.
EDIT: nevermind, read your second post... hmm.. is your wheel diameter set correctly on that computer?
sounds like your reed switch might be wonky, perhaps with a bad connection that gives an intermittent signal which the computer is interpreting as multiple circuit closures for every 'real' triggering of the switch.
Perhaps you should try a new harness and sensor.
EDIT: nevermind, read your second post... hmm.. is your wheel diameter set correctly on that computer?
#11
Klaatu barada nikto
Join Date: Sep 2004
Location: Southern NH
Posts: 1,453
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Originally Posted by robo
Nearly all cyclocomputers (with the exception of some early Avocet models IIRC) work with a reed switch which gets activated by the magnet..
sounds like your reed switch might be wonky, perhaps with a bad connection that gives an intermittent signal which the computer is interpreting as multiple circuit closures for every 'real' triggering of the switch.
sounds like your reed switch might be wonky, perhaps with a bad connection that gives an intermittent signal which the computer is interpreting as multiple circuit closures for every 'real' triggering of the switch.
Move the magnet a cm further away from the sensor and see what happens.
[You are the 'robo' !!!]
#12
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by cascade168
I think you might be on to something here. I would actually try to "de-tune" the magnet, given the symptoms. The reed switch could be bouncing and giving a double reading.
Move the magnet a cm further away from the sensor and see what happens.
[You are the 'robo' !!!]
Move the magnet a cm further away from the sensor and see what happens.
[You are the 'robo' !!!]
#13
Klaatu barada nikto
Join Date: Sep 2004
Location: Southern NH
Posts: 1,453
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Originally Posted by wroomwroomoops
Yah, ok, so have you actually tried moving the magnet? You have not said that you did. My computer just stopped working one time and it turned out that I removed the wheel to true it and re-installed it backwards (i.e. the magnet was on the wrong side of the wheel). I had removed the QR to grease it and re-installed it wrong.
Lot's of problems have simple solutions (= Occam's Razor). Maybe your magnet got whacked and it's not where it used to be.
#14
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by cascade168
Yah, ok, so have you actually tried moving the magnet? You have not said that you did. My computer just stopped working one time and it turned out that I removed the wheel to true it and re-installed it backwards (i.e. the magnet was on the wrong side of the wheel). I had removed the QR to grease it and re-installed it wrong.
Lot's of problems have simple solutions (= Occam's Razor). Maybe your magnet got whacked and it's not where it used to be.
Lot's of problems have simple solutions (= Occam's Razor). Maybe your magnet got whacked and it's not where it used to be.
But regardless, in my first post (just to satisfy your curiosity) I state that yes, I have dicked with the magnet, too:
Originally Posted by wroomwroomoops
I also tried adjusting the magnet on the spoke a few mm lower, or to the side, but it had absolutely no effect.
#15
Banned
Join Date: Nov 2004
Posts: 10,082
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Originally Posted by wroomwroomoops
It shouldn't matter, because an identical cyclocomp works fine when placed in that same cradle. If I had done some magnet-related problem, it would have shown with the other (identical) cyclecomp as well, but didn't. So, it's not the magnet-reed relay-cable-cradle assembly at fault (= Occam's Razor).
But if you had read my first post (just to satisfy your curiosity); yes, I have dicked with the magnet, too:
I also tried adjusting the magnet on the spoke a few mm lower, or to the side, but it had absolutely no effect.
But if you had read my first post (just to satisfy your curiosity); yes, I have dicked with the magnet, too:
I also tried adjusting the magnet on the spoke a few mm lower, or to the side, but it had absolutely no effect.
#16
Klaatu barada nikto
Join Date: Sep 2004
Location: Southern NH
Posts: 1,453
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Originally Posted by wroomwroomoops
It shouldn't matter, because an identical cyclocomp works fine when placed in that same cradle. If I had done some magnet-related problem, it would have shown with the other (identical) cyclecomp as well, but didn't. So, it's not the magnet-reed relay-cable-cradle assembly at fault (= Occam's Razor).
But if you had read my first post (just to satisfy your curiosity); yes, I have dicked with the magnet, too:
But if you had read my first post (just to satisfy your curiosity); yes, I have dicked with the magnet, too:
#17
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by Ziemas
What's up with the attitude? People here are trying to help you.
It shouldn't matter, though, since when I replace the cyclecomp, it works fine. So all parts being the same except for the cyclecomp, the speed measurement is fine - logic / basic debugging dictates that the problem is located in the cyclecomp itself, not the system that brings the rotation signals to it.
So far, I put the most hope in the dying battery theory. That, or it's cosmic rays.
#18
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by cascade168
Well, by all means, go for the extremely complex solution to your problem. Cosmic rays ..., whatever.
OK? Still mad?
#19
Senior Member
Join Date: Apr 2005
Location: Minneapolis, MN, USA
Posts: 1,152
Bikes: 1990 Burley Bossa Nova, 1992 Paramount PDG-70, 1993 Specialized Stumpjumper, 2005 Jamis Dakar XC Pro, 2007 Rivendell Bleriot
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Likes: 0
Liked 5 Times
in
3 Posts
Well, if the problem is internal to the computer, you're pretty much screwed..
I guess the one other thing you could check would be the contacts between the computer and the cradle. Again, if one of them was getting an intermittent connection, it could have the same effect as a misoriented reed switch or poor connection down there.
Other than that, time for a new computer.
(oh, and it's not set to km/h is it? )
I guess the one other thing you could check would be the contacts between the computer and the cradle. Again, if one of them was getting an intermittent connection, it could have the same effect as a misoriented reed switch or poor connection down there.
Other than that, time for a new computer.
(oh, and it's not set to km/h is it? )
#20
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by robo
Well, if the problem is internal to the computer, you're pretty much screwed..
Originally Posted by robo
I guess the one other thing you could check would be the contacts between the computer and the cradle. Again, if one of them was getting an intermittent connection, it could have the same effect as a misoriented reed switch or poor connection down there.
Remember, the problem is intermittent in the way that it will be measuring double speed for a while, then after a couple of hours (maybe because the temperature went down) it would work fine again, and there is no way for me to make it work fine when it's actung up, or make it work wrong when it's working fine.
Originally Posted by robo
Other than that, time for a new computer.
Originally Posted by robo
(oh, and it's not set to km/h is it? )
#21
Klaatu barada nikto
Join Date: Sep 2004
Location: Southern NH
Posts: 1,453
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Originally Posted by wroomwroomoops
Yeah... will try a new battery first.
Assuming that something as radical as replacing the battery with a new one might not fix your computer problem, you just might try swapping the sensor with your other bike, seeing as how you have an identical setup.
#22
Senior Member
Join Date: Nov 2006
Location: slow-mo peloton of one
Posts: 159
Bikes: Klein Quantum, Summit Comp Pro TR
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I've got the simple 2 step solution to your problem:
1. Remove cycloputer from bicycle. Apply large hammer to cycloputer.
2. Install new cycloputer.
It sounds like your 'puter has developed the dreaded Digital Alzheimer's Disease, the only cure for which I just described. One Hail Mary you might try first is cleaning the contacts on the back of the 'puter--a couple of quick swipes with 600 grit sandpaper should do it. Couldn't hurt to hit the ones on the mount as well, although since your other one worked fine that pretty much eliminates those. My Blackburn has a problem with moisture uptake into the mount when it's foggy out, which causes display errors similar to what you're describing. They stop as soon as I pull the 'puter and dry the contacts.
1. Remove cycloputer from bicycle. Apply large hammer to cycloputer.
2. Install new cycloputer.
It sounds like your 'puter has developed the dreaded Digital Alzheimer's Disease, the only cure for which I just described. One Hail Mary you might try first is cleaning the contacts on the back of the 'puter--a couple of quick swipes with 600 grit sandpaper should do it. Couldn't hurt to hit the ones on the mount as well, although since your other one worked fine that pretty much eliminates those. My Blackburn has a problem with moisture uptake into the mount when it's foggy out, which causes display errors similar to what you're describing. They stop as soon as I pull the 'puter and dry the contacts.
#23
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by xlrogue
I've got the simple 2 step solution to your problem:
1. Remove cycloputer from bicycle. Apply large hammer to cycloputer.
2. Install new cycloputer.
It sounds like your 'puter has developed the dreaded Digital Alzheimer's Disease, the only cure for which I just described. One Hail Mary you might try first is cleaning the contacts on the back of the 'puter--a couple of quick swipes with 600 grit sandpaper should do it. Couldn't hurt to hit the ones on the mount as well, although since your other one worked fine that pretty much eliminates those. My Blackburn has a problem with moisture uptake into the mount when it's foggy out, which causes display errors similar to what you're describing. They stop as soon as I pull the 'puter and dry the contacts.
1. Remove cycloputer from bicycle. Apply large hammer to cycloputer.
2. Install new cycloputer.
It sounds like your 'puter has developed the dreaded Digital Alzheimer's Disease, the only cure for which I just described. One Hail Mary you might try first is cleaning the contacts on the back of the 'puter--a couple of quick swipes with 600 grit sandpaper should do it. Couldn't hurt to hit the ones on the mount as well, although since your other one worked fine that pretty much eliminates those. My Blackburn has a problem with moisture uptake into the mount when it's foggy out, which causes display errors similar to what you're describing. They stop as soon as I pull the 'puter and dry the contacts.
Originally Posted by wroomwroomoops
I thought of this, and hence cleaned the contacts on the cradle and the cyclecomp. And then removed and reinserted the cyclecomp dozens of times, but that never helped one bit.
#24
2-Cyl, 1/2 HP @ 90 RPM
Join Date: Oct 2003
Location: NYC
Posts: 15,762
Bikes: 04' Specialized Hardrock Sport, 03' Giant OCR2 (SOLD!), 04' Litespeed Firenze, 04' Giant OCR Touring, 07' Specialized Langster Comp
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 4 Times
in
4 Posts
You need this.
#25
Sir Fallalot
Thread Starter
Join Date: Jul 2006
Posts: 5,286
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 13 Times
in
11 Posts
Originally Posted by slvoid
You need this.
Hey, this gives me a new idea; the reason why my cyclecomp shows double speed is... because I AM going at double the speed! Maybe I am possessed by the prince of darkness, giving me supernatural strength!
Last edited by wroomwroomoops; 04-01-07 at 03:13 PM.