Power meters for a bike have recently become one of the most popular technologies to objectively assess how hard you are working.
Power meters on spin bikes haven’t really been embraced as much , probably due to them being expensive and difficult to calibrate. However, there are a few manufacturers that have embraced the new measurement.
They work well when used alongside a heart rate monitor so you know hard you are working to achieve the output.
According to a Gym Jones article there are some concerns that you can’t compare the watts on a spin bike to one on an outdoor bike due to measurement of distance and speed being different but you can use it as a way to compare your training sessions on the bike. (This probably due to weight of the flywheel being harder to start turning than a bike but then needs less effort to keep it turning). The article suggests heart rate is a better objective measure between training on a spin bike and road bike
That aside it’s great for measuring performance objectively.
In choosing the best spin bikes with a power meter in addition to measuring watts I looked at the key areas of:
1. Console – what other information is supplied to monitor and track performance
2. Adjustability – that the bike is fully adjustable to give you the best chance of setting it up properly for a variety of sizes and get it close to the set up of your bike (if you have one).
3. Stable and robust – that you get the basis for doing a great training session without having to worry about any rocking or shaking
4. You get a smooth natural ride that is similar to a road bike
5. Price wasn’t particularly considered as it was the quality of the bike and monitor was seen as most important to get the best results from indoor training. The only bikes I’ve come across the Diamondback Fitness 510IC or the Bladez Fusion GS Indoor Cycle priced are more affordable but there are concerns with its’ overall reliability.
Keiser M3i
The console measures resistance level, time elapsed, RPM, watts, calories, heart rate (when you supply a polar compatible strap), distance (the distance measured on the computer is not miles or kilometres).
The M3i uses bluetooth to work with an IOS 7 device and above App, called Goind that allow syou to do further analysis of your workouts, which is great for spin bikes.
The power console has achieved the EN-ISO 20957-1 standard for its accuracy within plus or minus 10%. It is the only spin bike or indoor cycle monitor that has achieved this rating.
Watts is shown for the power being currently generated and the calories is the total used for the ride. The calculation for watts takes resistance level, RPM and uses a conversion table to determine the number being generated. The calories is calculated from the watts generated.
It is different to most spin bikes in that the flywheel weighs 8lbs, this can result in a more choppy pedal stroke but the resistance you are pushing against will increase the faster you pedal due to magnets being used for resistance like on a road bike. You can also increase the amount of resistance by using the resistance lever (you can see the level of resistance on the console).
It comes with dual pedals with cleats for SPD shoes on one side and straps and toe baskets on the other side for athletic shoes. The Q Factor for the bike is 7 3/4 inches which may feel unusual when compared to your road bike. The ride itself is stable and smooth.
Bodycraft SPR Indoor Cycle
The console measures resistance level, time elapsed, speed, distance, RPM, watts, calories, pulse (when you supply a 5 kHz Polar Compatible strap). The results of your workout can’t be stored or uploaded for further analysis. To do this you are going to need to record the information at the end of your workout.
The bike comes with a 38 lbs externally weighted flywheel that pulls through the pedals to give a fluid and natural pedal stroke similar to the one that you get when riding a bike. It helps to ensure you’ve got a full 360 degree pedal stroke.
The bike is fully adjustable with the seat and handlebars able to be moved horizontally and vertically to help you get the bike set up correctly for you and also to be a similar set up to an outdoor bike.
The handlebars include drop bars giving you more options for cycling training than you find with most other bikes.
The pedals have toe baskets and straps on one side for athletic shoes (you can use both sides of the pedal). The thread is 9/16″ so you can use your own pedals if you want. The q factor is 175 mm which is still wider than on an outdoor bike so will feel unusual but better than the Keiser M3i.
It provide a sturdy base for workouts and training – there isn’t any rocking or wobbling whether you are in or out of the saddle.
Could you please review budget bikes with a power meter? The only 3 I am aware of are the exerpeutic (paradigm) 575xls (250$) and the Tunturi (E30 (250$)& E35(275$)). I recently purchased the Tunturi E35 and am under the impression the power meter is extremely overestimating my power output as I dont think I should have an FTP greater than 500 watts (475 watts min with bursts of 700-800 for 75+ minutes). I was told by the distributor that 300$ bikes are inaccurate but I’m thinking this is overestimating my power output by at least a factor of 50-200%. It would be interesting to see if you guys get the same result.
Thanks for the suggestions. I’ll take a look at them. I can imagine the distributor being right with their opinion on the accuracy, unfortunately.
Thanks, I actually have been going crazy about this, I tried using a scale to make a torque (RPM) curve; and from this, calculate the power. I could only do this up to 45 RPM though, so I assumed it was linear. As far as I can tell, its over-reporting both calories and watts by 67% at 80-120 RPM. I analyze data for a living so this stuff bugs me, I think most people just say,” cheap bike” but I think its kinda silly they estimate calories and speed, when power, torque and rpm would be much more salient parameters for these things. Feel free to email me for any data, would love to see if you guys get similar results. Love learning about this stuff, but I am also kind of frugal, and seems you can get pretty good budget bikes, but then you jump up ~500 or so to get a reliable power meter and would love to see an article about data driven exercise which is becoming much more accessible to people without alot of money due to the affordability of smartphones and watches.