Commuting - Bicycle Computers - Are they reliable?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




georgiaboy
08-20-05, 03:01 PM
Considering purchasing a bicycle computer. Just weighing the decision in my mind. Trying to determine the necessity of having one. So, I will ask a couple of questions.

1)Is the data provided by computer reliable?

2)Is the operation of a bicycle computer high or low maintenance?

I don't want something so technical on my bicycle that I have to tweak it constantly. I just like to mount and ride for the most part.


djgonzo007
08-20-05, 03:14 PM
I've clocked the mileage on my daily commute with my bicycle computer and my cars trip computer and they were practically identical.

The operation is very simple you set it once and go.

ivan_yulaev
08-20-05, 03:16 PM
Err, you put it on, set the wheel size, and it's good to go for a year or two...


jeff-o
08-20-05, 03:50 PM
I've seen Cateye computers for as low as $20 CDN in retail stores. Why NOT get one???

Slow Train
08-20-05, 03:53 PM
The wired ones are good enough. How accurate do you need it? Back when I used one it repeatedly gave me the same distance for my commuting route (scientifically this property is called precision). Checking by other measures (e.g., car odometer) it might only differ by a few tenth's of a mile over a 50 mile course so I would say it is accurate to boot.

The wireless ones can get confused under high-power lines. A newer type are GPS units (and expensive). Don't know how accurate they are.

For the 2 former types there will be a tire size chart included in the instructions. The chart will give you a 'factor' to use when you set up the computer that allows it to know how far each revolution of the tire is. I've always used that factor as is from the chart.

For those who are really anal retentive you inflate the tires to riding pressure, get on the bike and have a friend chalk mark the tire and ground where they meet, then have your friend push you in a straight line one more complete revolutions of the wheel. You then can use this distance to derive your "personal" factor.

notfred
08-20-05, 04:05 PM
Mine matches up with mile markers on the road exactly, and it requires absolutely no maintenence at all. The only thing I ever do to it (after installing it) is reset the trip odometer and ride. I guess someday I'll have to replace the battery.

Walkafire
08-20-05, 04:17 PM
CatEye has done well for me... had mine for about 10 years. Replaced a battery once. Still works great... here is the simular 2005 model i have...
http://www.cateye.com/en/products/viewProduct.php?modelId=4&catId=6&subCatId=0
And here's how ya mount/calibrate...etc: http://www.cateye.com/en/pdfs/CD200N.pdf

I would not own a computer if it did NOT have Cadance... tis a must for me. I have seen a Trek that has a "Pace" feature.

georgiaboy
08-20-05, 04:29 PM
Thanks for the replies.

So far no posts expressing disappointment with a bicycle computer.

I read other places about the Cateye Astral 8 as being a good computer without spending a boat load of money.

bostontrevor
08-20-05, 04:39 PM
Get a Mity unless you really want the cadence feature. That's really all that separates the Astrale and the Mity.

Merriwether
08-20-05, 04:50 PM
Wired bicycle computers are very accurate if you take the time to set them up correctly. Roll out the distance-- don't use the charts in the manual. Put a bit of pressure on the tire to simulate a loaded bike.
Bike computers are more accurate than a GPS, actually. The bike computer will record your actual distance-- including the side-to-side wobbles. The side-to-side motion is too fine-grained for commercial GPS systems to measure. So, an accurate bike computer will have about a 1% difference from a GPS, I find.

The cadence function is definitely worth getting.

John Ridley
08-20-05, 07:24 PM
They're very accurate. I have a Planet Bike Protege 9, I got it because I was reading travellogues on CrazyGuyOnABike.com and liked the idea of having a thermometer on the computer. Also it's waterproof, my last computer flaked in the rain. I get a kick out of watching it go over 100*F on the ride home.

When you install it, put the magnet and sensor in a spot close to the hub. If you put it near the edge of the wheel, not only does the magnet unbalance the wheel more, but it flies by the sensor so fast that the sensor starts losing counts; until I figured this out, my comp started jumping all over hell when I got above about 20 MPH.

Slow Train
08-20-05, 07:47 PM
So far no posts expressing disappointment with a bicycle computer.


Ok - I'll give you a different point of view ;)

As I mentioned in my previous post I no longer ride with one. Nor do I ride with a watch. When I first started regularly commuting on my bike 10 years ago I found myself eagerly trying to set 'personal bests' while dodging through morning traffic. The computer gives you a number and every ride afterwards you are going to be chasing that number. I found I was starting to take risks and ride more aggressively than the situation warranted all so that I didn't lose my number.

The other reason I don't use a computer today is the ulitilarian aesthetic of cycling. I used to be the super road warrior geek with the computer, heart rate monitor and such. And that is all fine. But now - I much rather appreciate the simpler side of cycling. In fact, I'm rather taken now with the idea of getting a fixie.

By all means if your are interested in a computer get one! But be aware that it does change how you ride for better or worse

:)

Mehow
08-20-05, 07:54 PM
Bike computers are great, but I've only had one problem with them. (For Me) it seems as though the wire/cable between the cable and sensor is the weakest link in the durabilty of a computer. I recently solved this problem by getting a Wireless Cateye comptuer and am Loving it. A wireless computer may cost you twice as much, but I would expect it to last atleast twice as long. If your only going to see if a computer is "right for you" then getting a less expensive =<$20 cateye is still worth it.

Good Luck

jeff-o
08-20-05, 09:08 PM
Thanks for the replies.

So far no posts expressing disappointment with a bicycle computer.

I read other places about the Cateye Astral 8 as being a good computer without spending a boat load of money.

That's what I have, it works great. I got it on sale at Nashbar.

chroot
08-20-05, 09:56 PM
The best rear derailer on earth will require ten times as much tweaking as even the most temperamental computer. Almost all of them are rock-solid.

- Warren

ExPhysRoadie
08-21-05, 09:07 AM
I have the Astrale 8 and I've been very happy with it. I also had an older version of it on my mtb, but I lost the head unit somehow...

ks1g
08-21-05, 09:13 AM
I've used several - Cateye Astrale, Cateye Mitey 3, a low end performance Axiom, a Polar 150, and a Polar 720 (the new toy). For features/performance//reliability vs price, I suggest the Cateye units. The Mitey is on my commuter/tourer, and has been maintenance-free. Just take some care with routing and zip-tying the speed sensor cable to the bike.

The Astrale has 2 features you may want - cadence, and a rear-wheel speed sensor, which lets you see how "fast" you are going when the bike is mounted on a trainer.

Wheel calibration data is usually close enough (within a few %), a quick roll-out test on a flat surface will get you an exact number. Cateye has copies of all their manuals on-line, so you can answer the "how do I do that?" after you've misplaced the manual.

dobber
08-21-05, 09:27 AM
Most cyclo-puters are rated to an accuracy of +/- 1%. I've got a variety of brands out on my rides, Cateye (http://www.nashbar.com/profile.cfm?category=82&subcategory=1035&brand=&sku=1516&storetype=&estoreid=&pagename=) , Planet Bike (http://www.nashbar.com/profile.cfm?category=82&subcategory=1035&brand=&sku=4748&storetype=&estoreid=&pagename=) , Ciclosport, Specialized and the Flightdeck. On the same commuting loop I get consistent readings within +/- 0.1 miles on a 20 mile distance. Since actual tires sizes and inflation vary greatly (I've had errors of up to .5 miles on the aforementioned loop), I do the roll out method when setting em up.

The CateEye Velo 2 linked above is a nice, low cost quality unit.

georgiaboy
08-21-05, 10:18 AM
Ok - I'll give you a different point of view ;)

As I mentioned in my previous post I no longer ride with one. Nor do I ride with a watch. When I first started regularly commuting on my bike 10 years ago I found myself eagerly trying to set 'personal bests' while dodging through morning traffic. The computer gives you a number and every ride afterwards you are going to be chasing that number. I found I was starting to take risks and ride more aggressively than the situation warranted all so that I didn't lose my number.

The other reason I don't use a computer today is the ulitilarian aesthetic of cycling. I used to be the super road warrior geek with the computer, heart rate monitor and such. And that is all fine. But now - I much rather appreciate the simpler side of cycling. In fact, I'm rather taken now with the idea of getting a fixie.

By all means if your are interested in a computer get one! But be aware that it does change how you ride for better or worse

:)

Thanks for your post. Everyone should own that simple bike as well.