knock off power meter?
#1
Senior Member
Thread Starter
Join Date: May 2005
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
knock off power meter?
I know a power meter is the way to go ... but if you can not afford one what could be used instead?
Could you use a computer that measures cadence and if so has anyone done a comparison chart ?
Like 90 cadence is 350 watts ..
thanks for the input or thought/ideas.
John
Could you use a computer that measures cadence and if so has anyone done a comparison chart ?
Like 90 cadence is 350 watts ..
thanks for the input or thought/ideas.
John
#2
Super Moderator
Join Date: Jul 2004
Location: Ffld Cnty Connecticut
Posts: 21,843
Bikes: Old Steelies I made, Old Cannondales
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 1173 Post(s)
Liked 927 Times
in
612 Posts
Cadence is meaningless. It just measures how fast you're pedaling, not how hard you're pedaling.
__________________
Bikes: Old steel race bikes, old Cannondale race bikes, less old Cannondale race bike, crappy old mtn bike.
FYI: https://www.bikeforums.net/forum-sugg...ad-please.html
Bikes: Old steel race bikes, old Cannondale race bikes, less old Cannondale race bike, crappy old mtn bike.
FYI: https://www.bikeforums.net/forum-sugg...ad-please.html
#3
Senior Member
Join Date: Nov 2006
Location: Los Alamos, NM
Posts: 903
Bikes: 2008 fetish illustre
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 8 Times
in
1 Post
Poor man's powermeter: Measure speed. Next ride, measure speed again. More speed = more power. Ignore other factors like wind, etc.
#4
Senior Member
Join Date: Dec 2004
Location: Athens, Ohio
Posts: 5,104
Bikes: Custom Custom Custom
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Power is torque x rpm
So knowing your cadence is useless. SRMs and CinQos use strain gauges to measure the torque and then use the cadence to figure out power.
So knowing your cadence is useless. SRMs and CinQos use strain gauges to measure the torque and then use the cadence to figure out power.
#5
bf is my facebook.
Join Date: Mar 2006
Location: Greensboro, NC
Posts: 1,156
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The whole point of a power meter is too eliminate variables such as wind, heat, etc... which can change your avg speed for a given route. Watts is watts son.
#6
Senior Member
Join Date: Mar 2009
Posts: 984
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
To try to answer the question you want an ibike but they are not considered extremely accurate. Though, it is cheap at 199.99 and under ideal conditions they apparently work fairly well.
#7
Over the hill
Join Date: Mar 2006
Location: Los Angeles, CA
Posts: 24,365
Bikes: Giant Defy, Giant Revolt
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 995 Post(s)
Liked 1,203 Times
in
689 Posts
I think the next best thing is a heartrate monitor, but you're stepping back in time there.
__________________
It's like riding a bicycle
It's like riding a bicycle
#9
Senior Member
Join Date: Aug 2006
Posts: 2,501
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Likes: 0
Liked 42 Times
in
22 Posts
"HRM is way better than nothing and pretty good for steady efforts "
+1
Cadence is worthless. I can spin at any cadence at a low power output and a high power output. HR Monitor is the only poor man's alternative.
+1
Cadence is worthless. I can spin at any cadence at a low power output and a high power output. HR Monitor is the only poor man's alternative.
#11
My idea of fun
Join Date: Jun 2006
Location: Gainesville, FL
Posts: 9,920
Bikes: '06 Litespeed Tuscany, '02 Kona Lavadome, '07 Giant TCR Advanced, '07 Karate Monkey
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
Liked 59 Times
in
36 Posts
cadence and speed are not meaningless if you're doing all of your riding/workouts on a stationary trainer. Otherwise, yeah, it's meaningless.
#12
Senior Member
With a trainer, you have to have a consistent amount of pressure applied to the tire. This is why machines like the Velodyne and Computrainer have you coast down from a set speed - it measures the (extremely variable) rolling resistance of the roller.
So unless you never move your bike off the trainer, you always have the exact same pressure/tire, and you lock the tension thing in place, rolling resistance will vary. I rode a Velodyne (kind of like a Computrainer) for a few winters (along with an Technogym and even a Computrainer) and the rolling resistance really varied.
Power is a relative thing. It measures how much torque you're putting into the pedals. It doesn't take into account how you feel.
I actually think that HR is a really good way of handling workouts. It doesn't matter how much power I put out if I'm tired or sore or feel kind of sick or whatever. But a 166 BPM effort means I'm at the limit, and if I see 170 I'm exploding.
HR also changes relatively slowly, which is nice when trying to gauge an effort. There are TT type folks who set their powermeter to update every 5 or more seconds, so that the power numbers don't bounce all over the place (kind of like a car with a digital speedometer, it can be a bit distracting trying to hold a particular speed using one). HR has a natural smoothing built into it because it's hard to spike your HR (or drop it super quick, like 60 BPM in a second). If you set off on a steady effort, you can let your HR approach your target number (or, if you don't have a number, let it plateau naturally). Your power will become consistent once at that plateaued HR if you don't make any weird surges.
That's the key, the surges. The place where a powermeter really helps is when trying to do consistent efforts over varying terrain, like up/down hills. It's incredible how hard you have to work to maintain just 200-250 watts down a hill (consistently), and how easy you should do to do the same thing when heading back up. I virtually never have a flat looking power profile, but when "good" riders breakaway, it looks like they're racing on a track, their power is so consistent, but they're climbing a steep hill every 0.8 miles. You can't tell looking at their power output though - they ride so consistently.
I can sort of tell how many watts I'm doing based on HR, if I sustain the effort for more than a few minutes. If you get to use a powermeter (Computrainer at an LBS for example) then you can sort of graph your HR and power. This only works for sustained efforts.
For sprint/anaerobic type things, nothing replaces a powermeter.
cdr
So unless you never move your bike off the trainer, you always have the exact same pressure/tire, and you lock the tension thing in place, rolling resistance will vary. I rode a Velodyne (kind of like a Computrainer) for a few winters (along with an Technogym and even a Computrainer) and the rolling resistance really varied.
Power is a relative thing. It measures how much torque you're putting into the pedals. It doesn't take into account how you feel.
I actually think that HR is a really good way of handling workouts. It doesn't matter how much power I put out if I'm tired or sore or feel kind of sick or whatever. But a 166 BPM effort means I'm at the limit, and if I see 170 I'm exploding.
HR also changes relatively slowly, which is nice when trying to gauge an effort. There are TT type folks who set their powermeter to update every 5 or more seconds, so that the power numbers don't bounce all over the place (kind of like a car with a digital speedometer, it can be a bit distracting trying to hold a particular speed using one). HR has a natural smoothing built into it because it's hard to spike your HR (or drop it super quick, like 60 BPM in a second). If you set off on a steady effort, you can let your HR approach your target number (or, if you don't have a number, let it plateau naturally). Your power will become consistent once at that plateaued HR if you don't make any weird surges.
That's the key, the surges. The place where a powermeter really helps is when trying to do consistent efforts over varying terrain, like up/down hills. It's incredible how hard you have to work to maintain just 200-250 watts down a hill (consistently), and how easy you should do to do the same thing when heading back up. I virtually never have a flat looking power profile, but when "good" riders breakaway, it looks like they're racing on a track, their power is so consistent, but they're climbing a steep hill every 0.8 miles. You can't tell looking at their power output though - they ride so consistently.
I can sort of tell how many watts I'm doing based on HR, if I sustain the effort for more than a few minutes. If you get to use a powermeter (Computrainer at an LBS for example) then you can sort of graph your HR and power. This only works for sustained efforts.
For sprint/anaerobic type things, nothing replaces a powermeter.
cdr
#13
Senior Member
Join Date: May 2008
Location: Pico Rivera CA
Posts: 273
Bikes: trek 2.1, scott cr1 sl '06, ridley helium '10, univega gran premio and a look 595.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
just pony up for the wired version and you get the wheel.
https://www.competitivecyclist.com/ro...905.380.0.html
i ahve not seen a batter price for them
https://www.competitivecyclist.com/ro...905.380.0.html
i ahve not seen a batter price for them