ciclosport hac4 INFO

"jerryortega" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

Have any of you had any experience using the ciclosport HAC4

hrm,speed,POWER

Quoted message said:

monitor? I am thinking of getting one?

The heartrate and speed info are probably accurate.

"Robert Chung" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

"jerryortega" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

Have any of you had any experience using the ciclosport HAC4

hrm,speed,POWER

Quoted message said:

monitor? I am thinking of getting one?

The heartrate and speed info are probably accurate.

Using those two inputs to calculate power is probably a really stupid idea.

"Tom Arsenault" <[email hidden]> wrote in message

Quoted message said:

Power output is not accurate at all, but can only give you a very vague and hazy image of where
your power is while riding. For instance, riding a 9% grade hill at 17MPH, it rater my power
output as being 105 watts. Although not a power machine, I'd have to think I was putting out more
than that. Also, once while coasting downhill at 40+, my power output was above 300. So just kind
of ignore the whole power thing. As a HRM and cyclo-computer, it is good.

Have you entered your body weight and bike weight accurately? Mine seems remarkably consistent on
similar parts of the courses I ride. It may not be absolutely accurate compared to SRM cranks but it
does show a good record of my progress. My battery went down in the cold today though! All the best
Dan Gregory

"Dan Gregory" <[email hidden]> wrote

Quoted message said:

"Tom Arsenault" <[email hidden]> wrote in message

Quoted message said:

Power output is not accurate at all, but can only give you a very vague and hazy image of where
your power is while riding. For instance, riding a 9% grade hill at 17MPH, it rater my power
output as being 105 watts. Although not a power machine, I'd have to think I was putting out
more than that. Also, once while coasting downhill at 40+, my power output was above 300. So
just kind of ignore the whole power thing. As a HRM and cyclo-computer, it is good.

Have you entered your body weight and bike weight accurately? Mine seems remarkably consistent on
similar parts of the courses I ride. It may not

be

Quoted message said:

absolutely accurate compared to SRM cranks but it does show a good record

of

Quoted message said:

my progress.

I was sort of surprised at Tom's observations, too. I would have expected that the HAC-4 would
perform as you experienced (i.e., consistent though with unknown accuracy). BTW, if Tom is able to
ride up a 9% hill at 17mph, that's pretty impressive. For a normal-sized guy, that should be in the
ballpark of 1 hp.

Robert Chung said:

"Dan Gregory" <[email hidden]> wrote

Quoted message said:

"Tom Arsenault" <[email hidden]> wrote in message

Quoted message said:

Power output is not accurate at all, but can only give you a very vague and hazy image of where
your power is while riding. For instance, riding a 9% grade hill at 17MPH, it rater my power
output as being 105 watts. Although not a power machine, I'd have to think I was putting out
more than that. Also, once while coasting downhill at 40+, my power output was above 300. So
just kind of ignore the whole power thing. As a HRM and cyclo-computer, it is good.

Have you entered your body weight and bike weight accurately? Mine seems remarkably consistent on
similar parts of the courses I ride. It may not

be

Quoted message said:

absolutely accurate compared to SRM cranks but it does show a good record

of

Quoted message said:

my progress.

I was sort of surprised at Tom's observations, too. I would have expected that the HAC-4 would
perform as you experienced (i.e., consistent though with unknown accuracy). BTW, if Tom is able to
ride up a 9% hill at 17mph, that's pretty impressive. For a normal-sized guy, that should be in the
ballpark of 1 hp.

I've found the Hac4 to be very consistent and it produces repeatable results which is what I am
interested in getting from it.

Sparhawk

Sparhawk <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Robert Chung said:

"Dan Gregory" <[email hidden]> wrote

Quoted message said:

"Tom Arsenault" <[email hidden]> wrote in message
> Power output is not accurate at all, but can only give you a very vague and hazy image of
> where your power is while riding. For instance, riding a 9% grade hill at 17MPH, it rater my
> power output as being 105 watts. Although not a power machine, I'd have to think I was
> putting out more than that. Also, once while coasting downhill at 40+, my power output was
> above 300. So just kind of ignore the whole power thing. As a HRM and cyclo-computer, it is
> good.

Have you entered your body weight and bike weight accurately? Mine seems remarkably consistent
on similar parts of the courses I ride. It may not

be

Quoted message said:

Quoted message said:

absolutely accurate compared to SRM cranks but it does show a good record

of

Quoted message said:

Quoted message said:

my progress.

I was sort of surprised at Tom's observations, too. I would have expected that the HAC-4 would
perform as you experienced (i.e., consistent though with unknown accuracy). BTW, if Tom is able
to ride up a 9% hill at 17mph, that's pretty impressive. For a normal-sized guy, that should be
in the ballpark of 1 hp.

I've found the Hac4 to be very consistent and it produces repeatable results which is what I am
interested in getting from it.

Sparhawk

Quoted message said:

I'll have to go back and check my settings once again. I thought I had entered them pretty
accurately, but they may have been changed.

And the 9% at 17, it was a VERY short hill. Just so that there are no preconceptions that I am a
climber. Nope, short burst and hard up a short hill.

Tom

(Tom Arsenault) said:

And the 9% at 17, it was a VERY short hill. Just so that there are no preconceptions that I am a
climber. Nope, short burst and hard up a short hill.

The burst may have been too short for the HAC4 to calculate the power. Rate of elevation gain is
relevant to the power calculation, and any device that uses changes in barometric pressure to
estimate elevation gain needs time before it has enough data to calculate an accurate number. If you
were done with the climb before the HAC4 had enough data, then the results would have been skewed. I
expect these devices' power function is more accurate for sustained efforts.

--
Michael Fuhr fuhr.org~mfuhrOpen ↗

The HAC4 power calculation is useful only on extended efforts uphill. Even for that, it's crude. Try
climbing a dirt road, then a smoothly paved one. Or climb into a headwind, then without one. The
HAC4 really only knows about altitude gain, not rolling or wind resistance, which is can only
crudely estimate. It's a good computer, but it's not a power meter.

Dan

Michael Fuhr said:

(Tom Arsenault) said:

And the 9% at 17, it was a VERY short hill. Just so that there are no preconceptions that I am a
climber. Nope, short burst and hard up a short hill.

The burst may have been too short for the HAC4 to calculate the power. Rate of elevation gain is
relevant to the power calculation, and any device that uses changes in barometric pressure to
estimate elevation gain needs time before it has enough data to calculate an accurate number. If
you were done with the climb before the HAC4 had enough data, then the results would have been
skewed. I expect these devices' power function is more accurate for sustained efforts.

I believe also that the sampling rate is every 20 seconds (if it is the same as the CM414 Alti M -
same but w/o the heartrate info). That could also affect it on a "VERY short hill". It might not be
able to get an accurate sampling of data for the hill just as Michael suggested. In that he might
have transitioned into the 9% going 17mph and slowed down before the next sampling by the computer
was taken. I have noticed this on my CM414 Alti M.

James

"Michael Fuhr" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

(Tom Arsenault) said:

And the 9% at 17, it was a VERY short hill. Just so that there are no preconceptions that I am a
climber. Nope, short burst and hard up a short hill.

The burst may have been too short for the HAC4 to calculate the power. Rate of elevation gain is
relevant to the power calculation, and any device that uses changes in barometric pressure to
estimate elevation gain needs time before it has enough data to calculate an accurate number. If
you were done with the climb before the HAC4 had enough data, then the results would have been
skewed. I expect these devices' power function is more accurate for sustained efforts.

--
Michael Fuhr fuhr.org~mfuhrOpen ↗