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    What do you like in cycle computers?  
    I have a Shimano Flight Deck SC-6500 computer. This year it has `lost it's mind' three times. The latest incident was at the end of the Peach Century. It just seems like it re-sets itself for no reason. I re-program it and it works fine for a few months and then it has a nervous breakdown and it flashes to km/h.

Does anyone in the group have this problem? I had problems with my Trek computer on my mountain bike also, but not as frequent. The Bike Gallery replaced two of them. These computers seem fragile.

Lonnie Wormley

I had a Flight Deck that starting acting up during CO12. In my case, it seemed like it would push buttons "on its own." The trip counters would spontaneously start/stop, or it would think I was shifting gears on a chronic basis when I was just trying to survive on chip seal.

It turned out that some of the mounting screws were loose.

At no time did I have the thing completely reset. That sounds to me like a fragile battery connection. Make sure that the battery compartment is completely closed. If so, I would probably try to stuff the battery compartment (say, with some paper?) to make the fit a bit tighter.

Aside from losing power, the only other way the Flight Deck would reset would be via the two buttons on the back of the display unit itself. Those buttons seem pretty well protected by the hot shoe mount on the handlebars, so I can't imagine those being implicated.

The only other thing I can think of is that it's possible that the FD might be a bit sensitive to moisture. During the last two CO's, I always made sure that the display unit came into my tent and lived in my Sidi shoe when I was in camp. Theft protection and moisture reduction, all in one.

Jason "too many gadgets on my bike" Penney

I don't have one but I remember reading a review in Bicycling mag that panned it. They said (if I can remember), that it was big, bulky, and had too many problems. I think it got 2 out of 5 tires!

Maybe it's time to go w/ Avocet or Cateye?

Good luck,
Stacey Gray

I'm sure you've thought of this but have you tried replacing the batteries?

Steve "Usually missing the obvious" Heim

I've been very happy with my VDO wireless. The only drawback is that the batteries only last 1 year.

Steve Heim

I had a two year history of MAJOR problems with my Trek Radar computer (replaced twice, free) and this past July "my" bike shop manager told me Trek was fed up with the constant problems on all their computers by their contract manufacturer and RECALLED his entire inventory, directed him to take back any presented by disgruntled buyers and give them equivalent models from competitive lines. He gave me a Specialized SpeedZone Team Wireless computer and I love it!

Penny (lucky to live in Colorado) Overdier

Some of what you describe sounds like poor battery connections. Try adjusting battery contacts so they press harder against the battery. Also, as my Avocet 50 aged ( I bought it in 1991 ), I found that I had to tape the battery covers with very strong packaging tape to insure good contact. Perhaps that is your problem as well.

Curt Coleman

You can get replacement battery covers for your Av 50 from Avocet. Makes the connections work like new! No more fumbling with tape. You get 2 batteries with caps and o rings for 5.99. I guess they don't make an altimeter anymore. Too bad.


Thanks for all the Flight Deck tips. The battery cap is tight. I'll open it and make sure the contacts are good.

Lonnie Wormley

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So you're saying I should trade my Trek in for something new? Sounds like a plan. I'll call the Bike Gallery and find out the scoop.

Lonnie Wormley

I'm saying this was the cure for my frustration. I loved the Trek Radar until it seemed just looking at it (which we tend to do often, no?) was enough to cause it to seriously malfunction. I got so I carried a small pocket-sized spiral notebook, a.k.a. my cycling log/journal, in my handlebar bag all the time and entered stats from the Radar to the notebook during and after every ride to prevent loss of those stats. The only thing the Specialized lacks that the Radar had is air temperature. But people who know me well say I'm better off not knowing how hot it is anyway! A friend I often ride with put one of those tiny dot stickers over the ever-present temp reading one day with the astute observation that I gritch too much about the heat. She's right! Now, I just know it's HOT---but not HOW hot! Anyway, this new wireless computer is marvelous. How's the ole saying go, "Try it, you'll like it?"

Penny (lucky to live in Colorado) Overdier

If you're planning to trade it in, I recently replaced an old Vetta C15 with the Cateye Astrale. Many cyclists seem to like this brand/model, although it would be a step down from the Flight Deck.

Have you contacted Shimano to inquire about service bulletins or known problems? Maybe it's something as simple as a loose battery compartment, whatever the problem is, it should be solvable.

Hope everything works out for you...
Richard Rodriguez

FYI, I like my Cateye Astrale with cadence. Have learned a lot with the cadence.

Amy Ream

Does anyone have any suggestions or recommendations for purchasing an Altimeter?

I have seen hand held and wrist watch styles. There may be bike mounted ones, but I haven't come across any yet. Some measure in 3 or 5 feet increments and sample every 15 seconds or so.

Lloyd Van Roekel

I have a CatEye Cyclocomputer CC-AT100 on my road bike which compensates every twenty seconds and records one meter resolution. It also has a temperature reading and the normal other functions. No cadence, gear ratios, which gear I am in or the like. I like it very much and it seems to be pretty accurate based on the comparison of the altimeter we have in our car. I logged in the altitude of various places on some of my rides and then compared the readings to the one in the car after driving to the same places. The difference was not enough to make any adjustments necessary. Mine also has adapters and all kinds of other accessories which I am not interested in. Hope that helps you. Oh, the CatEye I have is not that expensive (around $100) which included the wiring and installation and replaced a Shimano I had which was miserable. I had it replaced twice and finally returned it for what I have now. I like the CatEye - it is rough, rugged, and easy to mess with.

Donald Lockridge

I also enjoy the CatEye model. When I first used it in the rain, however, it kept shorting out in the middle of a ride. This problem was solved by applying a tiny dab of car battery terminal anti-corrosion gel to its terminals.

Peter Goodkin

Here's another viewpoint on altimeters.

For many years I ran a cheap Casio wristwatch altimeter. This altimeter was a decent approximation; it gave me a rough idea of the extremes I was traveling in.

On Cycle Oregon XII, I saw a guy with a Suunto Vector. I immediately asked Santa Claus for one. This puppy ain't cheap, but I must highly recommend it for the following reasons:

1. It keeps a log of your altitude every 60 seconds!
2. It keeps track of your _cumulative_ altitude gain and loss!
3. It has a thermometer. This is important for accurate readings, because cold air is denser than warm air (duh!)

Because of the last, a wrist-held altimeter is not as accurate unless you aren't wearing it. So, what's the point? Well, I've found that wearing it on my wrist seems to impact the cumulative altitude reading by less than 5%. And, if you're finicky, there _is_ a handlebar mount for the Suunto.

Finally, I just hate a lot of expensive toys on my bike. It's bad enough having a Serious Bicycle, which just has STEAL ME written all over it. At least the altimeter stays with me instead of the bike.

My $0.01999736 worth (I'm using a Pentium).

Jason Penney

I had been waiting for someone to mention the Vector here. As it’s a wrist watch it’s not tied to your bike you can use it skiing, climbing, hiking, or for whatever and not just have it tied to your bike.

The logs are awesome! You can specify the checkpoints and less than 60 seconds is possible. You can enter a log and play its contents back. With this I was able to relive the Torture Ten without having to ride it again. I've had mine for a year and a half and am still finding new things it does.

For another 100 clams you can get the Advisor (same watch/altimeter/compass functions with heart rate monitor).

Don "'Check your vector Victor.' 'Roger.' 'HUH?'" Bolton

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Hey, guys, my Cat is removable, I can adjust for hiking, skiing, whatever I want. I can get a band to put it on. Depends on how much one wants to spend and what one wants to use it for. I have it for my cycle when I ride, as I am interested in how I did that day. If I want it for something else, I have it and for only $100.00. The Casio watch is fine, if that is what one wants. There are a lot of options out there.

Donald Lockridge" who is deliriously happy with what he has on his cycle."

While we are on equipment, I know the topic of cycle computers has come up before, but I was wondering if anybody has a few words of wisdom on the subject.


I have really enjoyed the Cateye Enduro 2 (comes in colors - WOW!) because the display has big numbers and my vision is not great at that range with my "driving" glasses on - and I don't want bifocals, etc.

I had one of the fancy Cateyes with the altimeter in it. I still carry that sometimes in my bike bag for the altitude part, but I can't see the fine print without lifting my glasses or staring at it for a while and running off the road (not an option I like).

So I guess my words of wisdom are - look at what you are thinking about buying and make sure you can see it at the correct distance with a quick glance!

I also like to have a CC that shows both speed and distance traveled from when I last reset it at the same time. Those are the functions I use the most when actually on the road. The rest I look at while stopped.

Rox Heath

I went all out 2 yrs ago and bought a Shimano Flight Deck computer that integrates with your Shimano Flight Deck levers and allows control of the displays with buttons on the lever hoods. It also displays what gear you are in, too.

I went back to a simple $20 computer after about 3 months for simplicity. Your decision on which to buy all depends on what your needs will be. Any bike shop will be able to help with that part.

Dave Stranahan

I like the Cateye Astrale. It has all the basics and cadence, which I find quite helpful. Also, the fancy Flight Deck costs $150 and the Astrale is about $30.

Amy Ream

If you are having problems with the graceful part (me too!) you may just suffer from another little quirk of aging...the numbers on those things (cycle computers) keep getting smaller! ;~)

If this is one of your little afflictions (they are all minor, now), check for numbers that you can read without your glasses. Remember, the designer of the display probably wasn't thinking about us!

Wireless computers are often whacked-out by cell towers (I had one that told me I was going 55mph on one particular climb on one of my routes. I was able to do that in the small ring, so I must have really been spinning! ;~) ). Wireless also have two batteries to worry about going dead.

That being said, I'm a minimalist. I want to know how fast I'm going, average speed, and how far I went, so the really simple computers are my favorites. Some folks need more information. If you are one of those, buy more features, run more wires, download all that info including elevation gain, barometric pressure, average temperature, and heart rate to your PC an have fun with it! Just go for the large print version.

Hope this helps.
Mark "wires and BIG numbers" Ramsby

It appears that either my computer or the wiring is not very water-proof. I had both my cadence and my speed go goofy on me. The speed fixed itself on the last, dry leg, and the cadence problem turned out to be the fact that the magnet slipped on the crank. So far, I'm batting zero on completing a ride with reliable statistics! [Computer is an Axiom 8.0C.]

Don "dirty bike in my cubical" Gross

I had a similar thing happen about 40 miles into yesterday's ride. My Cateye Astrale began reading a zero cadence and goofy speeds, yet the readings were blinking (meaning that it was getting a signal). I stopped to check my wires figuring I had either pinched &/or cut one, or the magnets had moved, but everything looked fine. As it turns out, there were particles of sand & dirt wedged between the contacts on the unit and base. I wiped the contacts clean & dry, and voilá no more problems.

Hope that helps,

Similar things have happened to my Cateye bicycle computers (both Astrale and other models). In addition to the sand/dirt that Richard mentions, water on the contacts will also cause unusual readings (or cause it to go to zero).

Craig Martinelli

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Don, I have "HAD" (you notice the past tense) Axion 8.0C computers with the same problem... I have taken them back and exchanged them… no questions asked.

One thing I noticed is, if the wire is stretched too tight where it goes into the "pick-up" for the sensors, either cadence or speed, it can "allow" a leak and defective readings. Just slightly loosen it, so there is just a small amount of slack in the line and it may help to solve the problem.

Another hint, put a little vaseline across the back of the computer. It helps keep moisture away from the contacts....I wonder if BAG BALM would work??

Dave the Slug

I had a problem with my Cateye shorting in the rain last year. With advice from the bike shop, I put one drop of car battery electrode paste/gel/liquid on each terminal and never had another problem.

Peter Goodkin

Does anybody know how to set up the tire sizes for Cateye computers? I don't know the formula, and I don't have the average tire size.

Stacey Gray

I don't use the CatEye, but their web site has all manuals for all of their computers.

The most accurate way to set it up is to roll out the tire. Mark your tire where it touches the ground and mark the ground directly under that point. Carefully roll the bike forward until the tire mark makes a full rotation and is back on the ground again. Mark the ground at this point and measure the distance. Most (if not all) computers want this distance in centimeters. If you measure in inches, multiply the result by 2.54. This is the number you want to program.

* Make sure your tire is pumped up to your normal riding pressure. Tire circumference varies slightly with pressure.
* Make the measurement on the wheel (front or back) on which you actually have the sensor.
* If you are measuring the front wheel try to steer as straight as possible.

Hope this helps.
Michael "computer nerd" G.

One more item to add to the list at the end: Make sure you are on your bike with your feet off the floor. This means you will need a helper to keep you vertical for those few feet.

Curt Coleman

While you're at it, go for 3, 5, or 10 revolutions and then divide the result by the number of revolutions to increase measurement accuracy. I did that when I set my Cateye several years ago; then the last time I set mine, I just used the pre-programmed value that was closest to my tire size (this was on my Performance Axiom 8C,not my Cateye). I've found it to be accurate enough for my needs, although interestingly enough, I believe I ended up using the sew-up size selection.

Don "Tad here and a skosh there" Gross

I've been meaning to try this both ways. On even days I have convinced myself that being on the bike is important. On odd days I'm pretty sure it makes no difference. The reason: even when you are on the bike, the tire still has the same circumference - it is just flattened at one spot. This flattening and the "slippage" between the road and the tire needed to make it happen accounts for the rolling friction of the tire, but otherwise shouldn't (or maybe it should :-) ) affect how far the bike moves for each rotation.

Michael "seeing is believing" G.

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  Page Last Updated: Jan. 20, 2003  
    CyclingSite > CO Collected Wisdom > What to Take > Bike Equipment > Cycle Computers  

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