Would have given 5 stars but the manual is poor. Setup and getting you top two choices to always display not clear. Enen simple things like a Metric AND English chart for calibrating your tire circumference.

I took my new speedometer out for a ride for the first time this morning I am truly glad I purchased it. Since I became more active in the last few months and spend more time on my bike, having an idea of how fast and far I was traveling spurred me on to push harder and put in a few extra miles. It works just as described and once you know which buttons to push, gives a good array of useful information.

Having said that (and I DO NOT say this with any intent toward racism) doesn't anyone at these Chinese companies have an uncle or cousin in the USA or England who can translate what should be fairly simple instructions onto something grammatical and understandable? The other problem with getting the three components properly placed is that the diagrams are extremely small and not very clearly drawn. BUT, I'm no Einstein but had it working within 15 minutes of opening the box. So, yes, buy this but either have a shot of whiskey to steady your nerves or rehearse a few of your favorite curses and have them ready. Great value for the cost.

I've never set up something like this before, and the instructions were not entirely clear to me, so I had to feel my way through this installation.

There are 3 circular batteries that come with this. You will need to use 2 right away: 1 for the LCD, 1 for the sensor.

The sensor opens by sliding it open; there's no hinge or snap. My little brain had trouble catching on to how to do that -- I almost broke it trying to open it. But it does slide open. Once slid open, turn the sensor upside down so the circular battery compartment cover falls out. The skinny washer will fall out also. Be sure to put both back in after you put the battery in.

The magnet fits well on the point where the spokes cross on the wheel. It's less likely to slide there.

The sensor's "arc" design should face out (not toward the wheel). The sensor should be on the fork facing the front of the wheel.

The magnet needs to pass very closely to near the top or bottom of the broad, flat surface of the sensor.

This works on my Mongoose fat-tire bike. I can only use it at night, so the pictures are hard to see, but they show how I set it up.

I lacked patience to roll the tire on a short tape measure to get the number to program the device, so I went to basic math. Wheel circumference = diameter x 3.14. Close enough. Do metric conversions as needed.

Good luck!

This bike computer is surprisingly solid for being one of cheaper options out there. They claim IPX7 waterproofing, and while I haven't tested it, it certainly feels like something that is built to withstand such environments. The case and sensor housing are properly injection molded with rigid plastic and the mount interface is well designed and well manufactured with reasonable tolerances and a high factor of safety. The batteries are standard coin cell batteries and easily replaceable. If you don't want a GPS bike computer, this looks like the cheapest option on Amazon right now, giving speed, basic trip stats, temperature, etc. Would highly recommend to anybody that doesn't need/want cadence data, power data, or gps navigation.

Enclosed a few photos to show that this unit CAN be mounted on the stem and not just the handlebars. I find handlebar real estate to be valuable and didn't want to occupy space with this speedometer. You'll need to reverse the clamp mount by uninstalling 4 screws, rotating the mount and then reinstalling. Not a huge deal but didn't see anything in the directions about the stem mount. As for the general installation the sending unit on the fork is probably the trickiest part, making sure the unit and pick-up magnet on the spokes are close enough to each other to communicate. I enclosed one photo looking down at the unit and fork, showing the need to angle the sender in slightly to make proper connection with the spoke magnet. Zip ties and self-stick rubber pad appear to be enough to hold things in place. Setting up the unit, while not 100% intuitive was doable with some patience. Most important part of ANY of these units is dialing your specific bicycle's wheel circumference (in millimeters) into the unit. Directions did have a chart with common wheel sizes, but for best accuracy it's a good idea to do a wheel "rollout" on a tape measure and use that figure as air pressure and even rider weight can influence the circumference. Check out available youtube vids. to see how this is done. Another point brought up by another reviewer is that this does NOT seem to have "auto-resume" after you've taken a break on your ride. It won't start up on its own once it senses a wheel rotation. You need to hit a button to resume your ride. Not a big deal really. Finally, my only concern with the unit is that the LCD display seems a bit dim, and nowhere NEAR as crisp and contrasty as it shows in the advertisement. Time will tell if it lasts!