I'm looking for an affordable (under $50) basic 8 to 12 function wireless cycle computer that will work at -20°F or colder.
Any suggestions?

I'll never go back to a wheel circumference computer. I've got a basic Garmin GPS (don't know the model) that suites me. No programming and I can move it from bike to bike. Lots of folks just use a phone app of some kind.

No specific models but if you're going with a wheel mag sensed computer I much prefer one with two buttons controlling functions.Andy

I don't know of any cyclometer (or phone or GPS for that matter) that works well at -20 F and below since the "weak link" at those temperatures is the battery. That said, i've had excellent service from several Cat-Eye models. I've only used their wired cyclometers but they've been economical, durable, accurate and easy to operate.

My IGPS50E, is spec'd at 14deg F. I would agree, the battery is the issue at those temps. I don't even charge my devices outside if it's below 32F, that's about the limit for lithium devices before you start to degrade the chemistry and ruin the cells. I have no problem using devices at colder temps, as long as they start indoors, and I don't deplete the cells below 20%.

Gotta ask, why would you ride in -20deg weather, that's got to be brutal?

Ron

I've had very good luck with the Cat-eye Micro wireless computers, my wife still use them. They work in all conditions(don't know about -20), but rain, fog, snow and heat hasn't killed them.
Now I use a Cat-eye gps unit my son got me a few years ago. I works well, hold a charge a long time. The beauty of it is that I can move it from bike to bike with out having to change any settings, you just have to buy extra mounts for it. The only real problem is that it sometimes loses the GPS signal under heavy leaf cover. The ride details can be loaded to something such as Strava so you can track you mileage etc..

Riding in -20ºF? Phone App, with the phone in your jersey pocket, underneath (presumably) a parka, so your body heat can stop the battery from freezing. Things like electric cars have to use specially formulated batteries to perform below freezing-- the batteries in consumer electronics (like bike computers) are gonna be super unhappy when asked to operate anywhere near or below 0ºF. If you don't want to go the smartphone route, there's always the tried-and-true technology of yesteryear:



Doesn't care about heat or cold.

-20, mostly none. As said it's a battery issue more than anything.

I ride down to -20F with Sigma BC 16.12 There may be some update by now of this computer. Battery operation has not been a problem in the cold. The screen has not been fading out at low temperatures, like for some other computers, and it has a backlight that does not cause a fade-out either.

Oops, I missed the wireless requirement. I presume there is a wireless version but I cannot attest its cold operation...

I love Sigma. I have met very few people who use them. A little hard to get used to (I am not a 12 year old computer genius)

but can you still buy those? those used to be fun on my stingray 50 yrs ago!

Oh yeah. MakeTheOne Mechanical Speedometer. Quite a few different models on Amazon.

haha amazing. mine used to have 2 fingers that fit into the spokes. this modern one has only 1. love the classic look but I would never got back to something that big. not even my Tony the Tiger growling handlebar noise maker

Hmm...

*looks at bright red comfort hybrid/errand bike*

*imagines sissy bar and ape hangers*

*and squeezy bulb clown honker*

*imagines it would be terrible climbing hills*

*kinda want anyway*

LET'S DO THIS!!!



Yup.

Semi-seriously... nope, can't be serious. -20F and riding bikes? Nope. Nopittynopenope. Also nope.

Only use I can imagine for a handlebar mounted doodad in winter might be for navigation and emergency comms, for bikepacking or long rides in unpopulated or lightly populated areas. There's nothing like that under $50. A phone could substitute and could be used in a handlebar bag protected in a map pocket with a USB battery in the bag for extended runtime. And Topeak and others have weatherproof mounts/pouches for phones. It might be possible to squeeze a dry chemical heat pack or similar doodad in those to keep the phone warm enough to run reliably in subzero temps.

Also I'd check to be sure there are lithium batteries available for any device. Those may perform reliably below zero. I used lithium AA in winter for my cameras and flashes that took AA and they worked fine into the teens, which is as cold as it gets in my area (traveling between Texas and Oklahoma panhandle). NiMH batteries were okay down to the 20s. My cameras that use rechargeable proprietary Li-Ion batteries tend to work at all temps I encounter. I've even stored 'em in the freezer overnight to test, but that doesn't get anywhere close to zero, let alone -20F.

Any wireless speedo/odo will use at least two batteries, often different types -- one in the unit on the fork, another on the display/receiver. If they both use lithiums they may work in subridiculous temps.

There are a zillion speedo/odo units on Amazon and elsewhere for under $50. I got a "SY" branded basic wireless computer for $12 in July -- the same unit is rebadged under various names. Works fine, weighs almost nothing, does what I need, and I won't be upset if it breaks or gets stolen. It's always virtually identical to my phone apps.

But I use the little speedo/odo only on my road bike for serious workouts to push myself. Can't say that it's actually helped. All my PRs and my one or two KOMs were sans-handlebar mounted doodads, back in the spring. I stripped off everything unnecessary to save weight and aero drag. Just the phone in my jersey pocket or saddle bag.

On my hybrids I only use my phone, which is in my pocket. I don't really need to know I'm loafing along at 12 mph.

I use a Cateye Strada Slim. Never used it in that type of cold. It uses replacable button Lithium 1032 in the sensor (the head is a different one). It does have large digits that might be handy when your eyes are half frozen shut.

I have found the 1032 LIthiums work at 0 degrees in other devices. The advantage with replacable is a warm battery can be kept on your person. I have been in sub-zero with my Canon F-1n with a Lithium and no issues (even if it did that camera could work without a battery, but no metering.) Rechargables are not as effective in real cold and can be damaged if run down, as RMueller said in Post #5 . In winter I carry my phone in a flapped shirt pocket instead of the belt holster to keep it warm.

Crud.
I must be getting old. I forgot about the battery issue.

Oh well ... Maybe I can find one of those front axle mount odometers that click with every wheel revolution.

The classic mechanical speedo/odo won't work. All I can find are for 26" and larger, (trike has 24" wheels) and/or are set for Km per hour.
I don't do Km's or the metric system.

I had a friend who, many years ago, used a SKU tire drive spedo and did his own calibration. He opened it up and put his redrawn "clock face" in it. I learned about measured miles for taxi and cop car calibrations from him. Andy