Sun Company Clip-On Compass for Bikes | Handlebar Compass for Bicycle, Motorcycle, ATV, or Snowmobile

Works as well as a compass can work. Before buying it, I verified my handlebars were non-magnetic (ie aluminum not steel) by using a magnet. Don't expect this to work near ferrous materials. This compass already has a little round rubber pad glued under the compass that holds it in place on 1" bars. It also includes a separate C-shaped rubber ring that needs to be used on 7/8" bars to keep it from sliding around. It's not rated for bars larger than 1", although it might stretch enough to fit up to 1-1/4" bars. Using the C-shaped ring holds it nice and tight on the 7/8" portion of my riser bars.In use, keep in mind its a compass and suffers from all the typical compass problems, including magnetic dip and acceleration and turning errors. You pilots will understand. In a nutshell, the compass will read erratically while turning and during sudden accelerations/decelerations (eg bumps and potholes). Straight and level, it works fine provided there are no stray magnetic fields (deviation) about. Keep variation in mind as well (the difference between true and magnetic north). It's a compass, not a GPS unit.The compass has an arrow and the letter N for North, letters for E, S, and W, and smaller letters for the intercardinal directions NW, NE, SE, and SW. The only odd thing is that there are three lines between the cardinal and intercardinal directions, in other words four divisions each 45 degrees. That's 11.25 degrees per mark. Just one line (for the secondary intercardinals SSW etc) or two lines (ie every integer 15 degrees) would have made more sense for a compass. Oh well...minor nit. It does a fine job showing me my general direction of travel, with no batteries required.

I bought this because the trails I ride on snake through the woods and there are many forks. I was getting totally lost because I have trouble remembering all turns at all the different forks in the trail. First ride I noticed that this compass seemed to pointing the wrong way and it caused me to take the wrong trail out of the woods and I ended up in the wrong place. Once I got back on the streets I could really tell it was way off, it was showing north as south. I turned west and it was still pointing south. When I got home I took it off the bike and it started pointing true north again. At first I though maybe some metal on my bike was throwing it off but that was not the problem, It only works if it is perfectly flat, which is never the case when its strapped to the handle bars of a bike. Even to tilt it back a little so you can see it at an angle causes the floating thing to hang up or stick so it doesn't register the change in direction at all. It will work if you take it off and hold it steady while you are sitting still, but not while you are riding, and that totally defeats the purpose of having it on your handle bars, you might as well just stop and pull a compass out of your pocket. I need something that I can look at while I am riding, so I know what direction I'm going after I take a different fork in the trail and this will not work.

This compass is exactly what I needed for my bike.Be aware: it's a tiny magnetic compass. So --Will it give an accurate reading when it's at an angle, or when you're bouncing around on roads and off-road? No, it won't. That's just the nature of a tiny magnetic compass. But if you're okay with stopping for a reading, or if you can accept that the reading will jump around a good deal on anything but a smooth road, this works great. That's all I need.Will it give an absolutely accurate bearing? No, it won't. But if you want a pretty decent bearing, it's great. Again, that's all I need. If I needed a serious navigational tool, I wouldn't rely on any kind of tiny compass and then blame the compass for poor results. I'd put a "real" compass in my pocket or pack.A larger compass would be more robust, but then it wouldn't fit on my handlebars. An electronic compass would be more robust, too, but it also probably wouldn't fit, and it'd be way more expensive.So for what it is -- a tiny, non-magical magnetic compass -- it's an excellent addition to my bike.

Works well, a bit pricey

I like the size and convenience, its accuracy is affected by the proximity to my bike computer. I will have to find a different mounting spot

Here to dispel some of the bad reviews for this compass.I took a chance on this little compass & compared it to my Cammenga H3... & as the picture shows, it is just as accurate.I also own a Sunnto M-3G which also agrees with the Sun clip-on compass.I clipped this on to my mountain bike handle bars, & it maintains the same accuracy.Took it down some jump trails & it holds on solid.It is a perfect, general direction compass, for quick reference while bike riding, or hiking... hence the 5 stars.I still prefer to use my Sunnto or Cammenga for land navigation, as they are better suited for use with maps... but this clip-on could work in a pintch.Now as far as the reviewers claiming the compass just spins... that's most likely because they mounted it on, or too close to ferrous or nickle metals, or too close to batteries (from a bike headlight or cellphone, or some other electrical device).Those claiming it only points in one direction... well... ALL compasses only point in 1 direction, which is Magnetic North.Edit... You may have accuracy problems if the compass is too close to steel bolts, like on your brake levers.Swapping steel bolts out with titanium bolts will solve this.

Not accurate

I just wanted something to put on my bike and this turned out to be perfect. It's easy enough to read, though small enough to be unobtrusive. My handlebars have different thicknesses, and don't have a problem with this getting and staying on. A little better quality than I expected for the price. I'm happy with it.