What's the best type of computer for speedometer accuracy? Wireless, wired, GPS, phone?

The distance, cardio, other features, etc., aren't a concern for me.

Links/brands/models of any good computers are appreciated!

As with most questions, it depends.

If you're riding across the Great Plains, no trees, buildings, or mountains in sight, and very few curves, a GPS (either stand-alone or on your phone) is probably the most accurate.

After careful calibration, my wired computers are within 0.5% of the distance shown by a GPS on an open course, or surveyed mile markers. (Note that Kansas and Missouri, at least, have road markers with little or no relation to distance.) I know a couple of beautiful rides where the mountains, curves, and trees interfere with GPS signals, and so the wired computer is (by far) the most accurate.

Wireless is similar to wired, except where it ain't. Near some power lines, neon signs, and high power headlights are some of those "ain't" places.

I love my Garmin Edge 500s as they are small, last a long time on a charge and are very simple in function. They use Ant+ sensors and once they are paired with your speed sensor, they automatically determine your wheel size and base distance off of that unless the sensor stops working.

For mapping and such, I have my phone.

How Accurate is your input?


Best for speed is timing lights, at the 2 ends of an accurately measured distance..

This is what they do for Battle mountain, and the Bonneville Salt flats..





...

If all you want is speed data, a simple cycle meter like a Sigma will do it. I have both wired and wireless mounts and move the head unit from bike to bike. Wired is the most trouble free, where the wireless requires a sensor, and mount that both require batteries. For navigation, distance, heart rate, etc. I use a Garmin 810, which I just saw on sale for $299, a lot less than I paid. I've had my Sigma for over 20 years and it has been good.

Heres my Sigma, not sure what the current model is.

Heres my Garmin 810. I cracked the screen on the Sigma loading the bike in my car, but it still works. The Garmin was "buggy" when I first got it, so I used the Sigma as backup. After firmware updates the Garmin is all good now. I just bring the Sigma out of habit, and to see speed at a glance as the Garmin cycles between screens.

How much accuracy do you think that you need?

Wheel driven computers are as accurate as your set up. Any measurement error, however, will be repeated over the length of your ride.
GPS can give you some strange individual readings along the way if there is a lapse in the signal but, over the length of the course it can correct itself.
The thing I like most about GPS, however, is it's lack of set up. Move it from bike to bike without adjustment.

One other thing: During my road running days I volunteered to help manage several big races. One thing I noticed was how much all the front runners "cut the tangents" on every turn. If there are a lot of turns, that will make a significant difference in the actual distance traveled. Don't expect your numbers to match up exactly with anybody else regardless how carefully you calibrate your computer.

I've always had luck with the Cateye units, excepting the incomprehensible instructions. But really any inexpensive ($25 - $40) wired or wireless non-GPS computer can do the job, Sigma is nice as well . One trick is to do a roll-out test to get a real measurement of the actual tire and wheel size in MM, than enter that into the computer.

Or you can buy the top of the line Garmin 1030 for near $600. I think it can make coffee, not sure, but can certainly tell you were to go for coffee To be totally accurate with that unit you need the $40 Garmin Speed Sensor, but can get it as a bundle.

Best is subjective at best.

Depends on so many things that only you know.

Sounds like all you need is a simple wired computer. As mentioned in several posts, a Sigma or Cateye wired computer will do what you need and won't cost you a lot of money. I have owned both and they were both very solid. I still have one of the Sigma computers on my hybrid bike. It's got to be around 10 years old.

I don't worry about how fast I'm going.

Problem solved.

I have a Garmin 235 watch.

It has a native running and cycling app. It automatically downloads if you have a smart phone. It's a 10 second process on a laptop if not. I can look at maps and graphs. It's pretty cool to see where a steep was and see what my heart rate was doing at the same time.

That's out of the box. It's relatively cheap to upgrade it and get much more out of it. Here's what I did.

For $24 I got a chest strap for HR, it's so so much more accurate than the wrist sensor. For free I got apps for the watch that I can use cross country skiing, downhill skiing, and a new app for cycling that shows a lot more data on the screens. I turned off the email/text functions but if that's important to you, it's capable.

It can connect to strava and facebook, I don't but if that's important to you, it can.

It'll go 12 hours on a single charge in GPS mode and a week or so as a watch.

A cadence sensor is $32 if you want it. It's ANT+, I think some wattage meters are compatible with it. I don't use them (or can't justify the price) so I can't really say though.

I love having a single unit to track all my activities, plus, I can wear it at work to track my steps etc and wear it to bed to track my sleep.

It does not need to piggyback of a cellphone GPS to work. I have a flip phone (on purpose) so this is also a big feature to me.

I use iPhone with:
Runstastic RoadBike Pro app ($4.99)
SunDing BlueTooth speed/cadence sensor (Amazon $14)
iPhone handlebar holder (Amazon $12)

Good luck

For your needs, a simple wired computer, as long as the circumference of the wheel is accurately measured and entered.