Which GPS sportswatch

Which GPS watch do you recommend? I want one to assist with my century training and to verify my attempt. I have been looking at various Garmin and Polar products and though I’m convinced they are the tool for the job, I don’t know which one to buy. I don’t need any navigation, I just want time, distance and speed - heart rate and elevation features would be nice but not essential.

The one problem I can foresee is battery life. The Garmins I’ve been looking at have a training mode battery life of around 15 hours - my century is going to take me at least 14 hours and probably considerably more. Nothing could be worse than getting to mile 94 and then finding the battery on the mileometer has gone dead so I need a long battery life.

So there you go - time, distance, speed and a battery life of around 24 hours. What do you reckon?

All you need is an Android smart phone. Covers your communication, entertainment, GPS and more in one package.

On the Android, a good app is called “Endomond” does all your looking for.


…or an iPhone or even iPod Touch*, which is what I use with an app called MotionX GPS (99ct). It can do a lot more than a GPS watch at a similar price point.

*requires an extra BT GPS receiver and a jailbreak

I don’t have any experience with GPS devices, so I can’t recommend anything. However, I can think of many things worse than a dead gps battery on a century ride. Getting hit by a car, multiple flat tubes, a broken seat base, running out of food/water in a remote location, all worse than a battery life issue.

For 24h battery life you would need another accu pack for the iPhone/iPod Touch.


The Garmin 310XT has a battery life of 20hrs… you should be done by then :slight_smile:

I would recommend for a dedicated GPS, not a phone. Using phones just don’t give you the resolution when you get any kind of obstruction and tend to slaughter your battery. I have a Garmin and have done for years, they from what the reviews say, have the best receivers and have great connectability for tracking. If you get one with a heartrate strap you wont go wrong for training, they really help you understand what your body is doing.

Joe Baxter has just got the Edge 500, it is really impressive. When my 305 dies I will have no hessitation at buying one! It find the satalites really fast, it worked in a forest with no problems and has great features. My only critism is that it does not have a barometer in it, it uses the satilites for height and that is never the best (but better than mine!).

He bought his on line through ebay and got a really good deal.


This looks perfect, but:

  1. How does the Edge® 500 hold up with multiple UPDs if attached to a handle bar?
  2. How you you mount or hold this on a unicycle without a handle bar?

The unit seams really ruggid, all the Garmin products are. I can say that 305 has been down the road several times and looks really battered; but not only still works but is still waterproof. The Edge comes with a handlebar mount but it does not need to be fitted there, you could fit it on the seatstem if you want. Joe just puts his in his bag for off-road as you don’t really want to read what it says until you get back. If you want to read it while you ride and don’t have a handle bar (they are recommended for doing distance), then I would look at the forerunner series as they fit on you wrist.


GPS watch

I would like to know if anyone has used this wireless speed/cadence sensor (see URL below) on a unicycle. My wife runs with a Forerunner® 405 and I have often thought of strapping on the Heart Rate Monitor and giving it a try for myself but I have heard that just about any “wireless” sensor has very limited range. My current set-up is an iPhone with Cyclometer. I have iHome speakers in my CamelBak so it announces info at set time/mileage intervals. It’s just she’s not using the watch much anymore and I paid +$200 for it so I was thinking another $65 investment might make it worth while. Any thoughts?


I am considering the Garmin 305( sold with heart rate monitor ). Online reviews are very good. Walmart is selling this unit for $128. Walmart also has a good 90 day return policy if not satisfied.


My thought is why bother with a cadence sensor? With a fixed gear unicycle, the speed can be translated into cadence by multiplying by a constant. With a guni you have two different constants to choose from, but if you looked at your speed on any part of the route (e.g. the big hill) all you would need to remember is what gear you were in on that part of the route to calculate a cadence.

I would just strap in on and give it a try. After looking at the data you could decide if a cadence monitor would be of any use. If you do use the Garmin 405, let us know how you like it. I have been thinking about getting one (but without the cadence monitor.)


I have a polar cs300 cycle watch with a cadence sensor.(no gps, just heart rate, speed, cadence, distance and time) It makes life so much easier. It gives me my maximum and average cadence and I can even play interval games…trying to maintain a certain cadence (which is better than speed as it is affected by wind, terrain etc.)


cadence = constant x speed

Anything that affects the speed will also affect cadence (unless you have a guni.)


yeah i dunno scott? in my experience this has not been so, perhaps I defy the laws of physics? :sunglasses: I thought speed = distance/time and work done = torque x cadence? I’m not picking a fight here…I’m genuinely interested in how to measure performance.

Performance? Well that is a whole different topic and one I do not know much about. I go on rides, try to work a bit and typically look at my average MPH to get a sense of how my workout compared with yesterdays on the same route. I would enjoy playing with the Garmin GPS and the heart rate monitor to get a better idea of my progress.

I did work out some details about cadence in a post a while ago. Here is the link:

As discussed in the link, for a (fixed gear) 36" unicycle,

cadence = 9.58 X MPH

OK, I just saved you $60 for that cadence monitor.

You are welcome.


Scott…I just spoke to my dad who is an engineering genius and he says you are indeed correct.:smiley: A certain speed WILL always equal a certain cadence on a unicycle. The only thing that the elements will do to a person is make it harder physically to maintain that certain cadence.

Very neat link BTW…I better be careful next time I ad a couple of km/hr for effect :wink:

Cadence calcs

I found this somewhere, its quite handy :slight_smile:


Wheel Circumf. Cad Speed
26" with K-rad 0.00213 110 14.058
26" with K-rad 0.00213 120 15.336
26" with K-rad 0.00213 130 16.614
26" with K-rad 0.00213 140 17.892
26" with K-rad 0.00213 150 19.17
26" with K-rad 0.00213 160 20.448
26" with K-rad 0.00213 170 21.726
26" with K-rad 0.00213 180 23.004
26" with K-rad 0.00213 190 24.282
26" with K-rad 0.00213 200 25.56
26" with K-rad 0.00213 210 26.838

Coincidentally I did this on an Excel spreadsheet
more or less at the same time Alan left his post.
Everything is in KM/hr, but its definitely a worthwhile exercise,
especially if you have a wide variety of tyres and uni’s.
Basically measured the wheel circumference, converted it to kilometers,
and just do a wheel circumference x cadence formula in the speed column.

The chart I posted didnt have a 26" so you have filled the missing gap :slight_smile: