So the chart with the wheel measurements is wrong. I have 700c wheels with 23c gp5000s and according to the chart it should measure up to 2096mm’s. Well I measured the distance ridden with gps on my phone and the cateye would always come up .02 short. Well I measured my own wheel and it actually came up to 2154mm’s. There chart is way off so make sure you just measure your own wheel. The formula is easy just measure from the center of your wheel to the ground and multiply it by 6.28.Upon trying to install the hardware all the rubber bands snapped so I used a hair tie to put the computer on the stem and one of the zip ties for the sensor. I put some electrical tape behind the sensor to move it closer to the spokes as the fork was right on the edge of 5mm’s. Seems to be holding up.Here’s some more information from the manual. With everything together it weighs 25.5grms.This is a nice unit. Would be nice if base rotate so I didn’t have to use zip ties when mounting to handlebar. But it only picked up my speed part of the time. The issue is I have disc brakes so clearance is too much to keep the signal to wheel. Gave it to my daughter.I bought the Slim because of the short wait time for delivery. I took a chance that it would replace my Strada Wireless, even though the ad said "recommended for road bikes". My Strada Wireless broke in a crash so thought I would try this. The important difference is the size of the sensor and the expected distance between the spoke mounted magnet and the sensor. My mountain e-bike has too much space between the magnet and the Slim sensor. I called Cateye and they said the Slim is compatible with the "standard sensor". I left the Wireless sensor in place then mounted the Slim to the Wireless handlebar mount since it seemed to slide right in. So the only thing I replaced was the broken Wireless computer with the new Slim computer. Just had to recalibrate and go through the entire setup procedure for the new Slim. After a couple of rides, I found the Slim had reset itself, apparently erasing all my previous setup and calibration. Not good. I asked Cateye if it could have been because I used the old Wireless handlebar mount. They told me that sometimes the computer battery in the Slim loses contact and I should replace the factory battery with a thicker CR1620. Also not good. I wish I had known this before my original setup. So I will start over again in addition to estimating what my odometer should be reading now. Beware of the battery. About $5 to replace it with the recommended battery.I agree with the other top negative reviews. This particular model of computer seems to be very flakey.When I first received it, it was within 1% distance traveled, average speed compared to a GPS unit that I own. Eventually I noticed that over time, that variation increased. I then noticed on subsequent rides that the unit would be displaying a speed of 0 mph on occasion, or, when I was traveling very slow, it would register a very high speed. It appeared to me to be "lagging" (i.e., I just came down a big downhill, where it registered 0, then on the uphill it seemed to be registering the downhill I had just done).I've been riding for over 40 years, and had many different cycle computers over the years (my all time favorite was an old Avocet, I wish they were still made!!!) I've ridden thousands of miles, and toured on several continents. I really WANTED to like this computer. It is good looking and easy to install. It's very basic, but that's all I'm looking for.But please, just work! Unfortunately, it seemed to work for the first 30 days (which is the Amazon return window), *then* it started flaking out. There is a battery in the head unit and the transmitter, so I replaced each with a fresh battery, and tried various placements. I thought maybe the WiFi or bluetooth signal from my phone was somehow interfering, so I left my phone at home. I tried every possible remedy I could think of, and finally came to the conclusion that the unit is just BAD.So, Cateye has a 2 year manufacturer warranty. The Amazon window for return has closed, so I'm going to attempt to deal with Cateye directly.EDIT: I gambled and purchased a second unit (after Amazon took the first one back minus a re-stocking fee because I was past the 30 day window).It seems to MOSTLY work, BUT, when I turn on Apple Music on my phone I notice that this unit does the same thing as the first unit --- it will sometimes show the correct speed, but sometimes drops down to ZERO. If I turn off Apple Music on my phone, the problem goes away.So, it seems like there must be some RF interference being generated by the Apple Music program? The thing is, with the first unit, I experimented with completely shutting off the WiFi and cellular data on my phone, or just leaving my phone at home, and still had the problem. So I think the first unit must have become permanently damaged, perhaps by playing Apple Music? So for now, the unit appears to work as long as I am not playing music on my phone while riding.I'm giving this 4 stars, although I had a problem that was caused by me. I have it mounted on my bar stem and if you press on the lower half of the computer for a few seconds all of your data is reset to zero. When I'm walking my bike I have a habit of holding it via the stem and I've lost my current ride data several times already. Not the computer's fault.Otherwise, I'm pretty happy with it. I was in a hurry to install it for a big event and I just went by the default settings for my 700x23 tires. It seems to be several miles low after 400 miles and so I'll do the rolling wheel method to get the correct number.My only gripe in the setup is they claim you can turn off a particular setting so it doesn't show up when you cycle through the computer. I have no need for the clock but I cannot figure out for the life of me how to hide it like the manual says you can. It is only one additional button press to cycle past it anyway.I had to add a few rubber spacers between the sensor and fork so the spoke magnet would be within 5mm and read correctly but I have special wheels. I imagine a regular spoke wheel would work without any modification.I haven't had the "pleasure" of seeing how waterproof it is in the rain but I'm sure I'll find that out soon enough. It looks like a solid unit. I love how I can just press anywhere on the lower half of the front of the computer to cycle through the various displays.going over 26 mph the thing goes to zero. Reading all over the place.The Cateye Strada Slim has all the functions I need but unfortunately it keeps resetting itself at totally random intervals, and all the data is lost. It is really frustrating to have to keep inputting the basic data (mph, wheel size, clock etc.) and start all over again. The last time I did this it worked for a day then the clock went haywire and changed itself twice. There appears to be something seriously wrong with the algorithms!I've just been reading several reviews highlighting exactly the same problems so why isn't Cateye doing anything about this. We really deserve our money back on this item. DON'T BUY THIS COMPUTERI have used Cateye Strada for a least the last 10 years and never had a problem.This one has crashed on me 4 times in the past month whilst out on a long ride. Very frustrating.?Replacement on the way. Hoping this is a one off ?I haven't done many reviews at all, but thought it would be worth warning people about this product. It was easy to install and worked well for a while; however, then started to re-set itself. Everytime I went for a bike ride it would re-set and I would have to go through the whole installation process again. PLEASE AVOID THIS PRODUCT.The Cateye looks good and the sensor is less sightly than normal sized sensors. However, the cateye does not seem to be able to hold on to its settings. I have programmed the wheel size and other settings multiple times, only to find the screen 'glitching' and needing reprogramming the next time I want to ride the bike. Avoid.Battery tends to only last for a month or so. Battery size also not common and you won't find it easily available on shops so will have to order especially.Cateye usually excellent - not in this case, it seems. Rather than go through the hassle of continually ordering and replacing batteries, I am going to have to buy a new cycle computer. Really disappointing.