HRM/Cyclocomputer help

I use the HAC4 ( www.hac4.com ). It does not tell what gear you are in, but it does all the rest...speed, temperature, several different count down/up functions, heart, altitude, cadence, except for the cadence wire the handlebar unit is easy to transfer between bikes, and uploads to the computer and presents a nice trip profile which you can put comments in and so forth. I am personally satisfied with it, but the software is a little clunky. I wear it as my everyday watch too. I got mine from a mass distributor on Ebay for about $300 USD.

Quoted post said:

Originally posted by gregk
Sorry for the newbie questions! Any help would be appreciated greatly.

I'm a newbie too, and I had the same questions only a little while ago 🙂

I did a TON of research (wanting the same features in a cyclecomputer as you) and after deciding that there was no way to really avoid spending quite a bit of money, if you wanted something top notch, I narrowed it down to two; the Polar s720i and the Ciclosport HAC4.

I tried both, and came to the same conclusion as quite a few others on this cycling board and others on usenet; that is, the Polar s720i is a top of the line heart monitor that has cyclecomputer functions, and the Ciclosport HAC4 is a top of the line Cyclecomputer that has heart monitoring functions...

I already have a Shimano flight deck computer on my mountain bike and I was considering putting the wireless harness for it on my road bike (the Shimano STI levers integrate well with their flight deck computers) and because I was thinking I already have computer, I should trend towards the s720i to get the topflite heart monitoring functions and then I would just use both on the road bike at the same time.

I know how clean and efficient it would be to have one computer that did it ALL, including the gear indication, but neither the HAC4 nor the s720i do this and they are about as top shelf as you can get so you might have to lose the idea of getting gear indication unless you also go with two computers on your bike.

Although I believe that the HAC4 is a fabulous unit, and I got the s720i, I seriously believe I would be very satidfied with either, the HAC4 does do the "virtual" calculation of output (watts) but this calculation is based on a very loose formula that doesn't take into account things like headwind, and abrubt inclines that may lurch up and level off inbetween the HAC4's sampling rate (every 20 seconds) for these reasons, many consider the wattage calculation as grossly inaccurate on anything but a set of rollers, and there are accuracy issues even then.

The polar unit has a FAR more accurate closed loop method that measures wattage as a function of chain tension (measured resonating frequency of the chain will tell you how much force is being applied) and this can then be plugged into a formula to extrapolate wattage in a way that is far more accurate and much closer to the way actual clinics and sports labs measure output... The catch? the measuring device must be purchased seperately and costs around $350-400! Like buying another computer 🙂

Both units use chest straps... Of note is that the Polar strap sensor is "sealed" meaning that you cannot change its batteries yourself and you have to by a whole new strap... This is not as bad as it sounds though because the batteries have a lifespan of two years if you use the unit 2 hours every single day... It only expends battery power while you have it on so unless you train heavily every day, it should last much longer than 2 years... When you have to buy the replacement its a reasonable $30... You can change the batteries in the HAC4 sensor, but you must be extra careful about seals and such because sweat is extremely corrosive... With the polar strap I just take it off and hang it up on the doorknob of the garage and forget about it till the next ride... Also you can actually swim while wearing the polar unit, something that is not specifically recommended with the HAC4, so if you're into swimming, there you go 🙂

Both units will do cadence, but with the addition of a cadence sensor that you buy seperately, but for a much more modest price of around $35. Both units come of course with the speed sensor.

As mentioned before the HAC4 sampling rate is every 20 seconds while the polar sampling rate is adjustable down to every 5 seconds, so the resolution of the computer graphs is more realtime. Both units will store multiple "ride" info files and a gross oversight in the s720i has been corrected where the unit will now pause for 30 minutes before terminating a ride recording. Previously is would stop recording after a pause of 5 minutes which was BARELY enough time sometimes to run off the side of the road, pee and run back! Any unit you buy now should be the newer variety with the longer pause ability. So you can have that one 50 mile datafile instead of two 25 mile files.

The polar will not tell you things like gradient of the climb or detailed gradient percentage over time info like the HAC4, but it will tell you the current altitude and total ascent vs any other function (time, heart rate, speed, cadence etc) and for me, that is more than enough 🙂

SO many features to compare and describe I could probably go on for hours, but trying to keep it short, I have to recommend the Polar unit for the simple reason that anything you bolt on your bike, wether it be a fancy piece of electronics, or a new crank, should do only two things, make you ride better, and make you ride longer. Because the polar does a slightly better job at showing you real progress (heart rate functions) as in recovery rate, rise rate, resting rate, BPM vs "anything" in my case, it makes me do both... The software has a very intuitive and real way of showing you that your sustained effort is resulting in faster recovery times and lower overal heart rate the longer you train. The HAC4 showed basically the same information, but i found it more difficult to exctract evidence of real progress from its computer graphs.

As time goes on, and I become far more serious in cycling, I will want to measure wattage accurately, and will shell out for the wattage sensor. With the HAC4 , in that specific arena I will always be left wanting.

Monitoring your heart performance I think goes much farther and more clearly toward making you a better cyclist. Much moreso than saying to yourself "I rode 20 miles today with an average gradient of 2% for the first 17 minutes and 3.5% for the next 12 minutes" etc... Such statements are open ended without measuring your heart performance accurately and are more a superficial indication of how far you "went" and how you "went" and not of how far you've physically progressed (or slid back)

When I ride, 99.9 percent of the time the s720i displays only 4 things; Time, heart rate, above or below target heart rate, and cadence... when I get home and download the info into the computer I can get all the fancy-schmancy heart rate vs altitude vs speed vs cadence vs temperature etc from the graphs...

Seeing the calendar displayed on my PC that shows all the rides I've done by day, and time above, below and within target heart rates for the week has been an INVALUABLE tool for training and for inspiration... There is something about sticking to a schedule you can reference that makes you want to train more... I look at the calendar and see i have 3 more days left in the training week to hit my total of 150 miles a week, its almost like a very FUN and healthy version of paying your "body bill" 🙂

Oh! forgot to mention that both units also tell you how many calories you burned, cumulatively and on specific rides and days, and that is another amusing incentive... I love the days when I track that I ate 2300 calories and rode for 1800 calories expended and at the end of the day I sit down and say "Almost broke even!" *laughing*

I wish you luck on your quest to find your cycle computer/HRM I hope some of the information here is helpful to you... in the end, I think you will be satisifed if you bite the bullet and get either of these two great units, both are solid performers and well made, and despite usenet messages that each one had its issues with losing signal, I had no trouble of any kind in that regard with either one, and I used them both for several weeks before deciding on the Polar...

Feanor

Wow, Feanor! Thanks for the huge reply!

One more question: Does anybody have both a separate HRM and cyclocomputer just for the sake of having more information displayed at one time? For example, Heart rate on the HRM/ Time, cadence, current speed on the computer. Just curious.

Quoted post said:

Originally posted by gregk
Wow, Feanor! Thanks for the huge reply!

One more question: Does anybody have both a separate HRM and cyclocomputer just for the sake of having more information displayed at one time? For example, Heart rate on the HRM/ Time, cadence, current speed on the computer. Just curious.

I sort of had this by accident for awhile. The first computer I bought was a FlightDeck. Although it did it's job quite nicely, it was missing 3 things: HRM, altitude, and recording. I finally broke down and purchased a HAC4, so for a while I had both. When I sold my old bike this fall, however, the FlightDeck went with it, so now I'm down to just the HAC4.

At first I thought I'd miss having the extra info available, especially since I wouldn't have switches built into the hoods to change the display (which is how the FlightDeck works). Surprisingly, though, I haven't missed it at all, and I'm quite content with the HAC4. I've found that all I really need are speed and cadence. Plus, the HAC4 has a little bar graph for heart rate that's visible all the time, so I can see if I'm redlining the motor. As infrequently as I check additional stuff like distance, it's not a big deal to click a few buttons.

BTW, if you really want to see the gear displayed, I think your only option is the ErgoBrain from Campy. The FlightDeck does this if you've got a Shimano setup, and that's another thing I thought I'd miss. Especially with all the hills here in North Georgia, it's nice to know how far you've got before you run out of gears. Again, to my pleasant surprise, that hasn't been a problem for me. It's true that when I had the flight deck I was paying a lot of attention to the gear display. With the HAC4, though, I've found that it's really no trouble to take a click glance back at the cassette and eyeball the gear. (The fact that I went from a triple to a double up front might have made that a little easier.)

BTW2, if you decide to go with the HAC4 and you want cadence (for me, it's essential), there are two different cadence kits available. (I know, since I bought a second cadence kit for my commuting bike.) Both are wired, but one has a thinner wire and is permanently attached to the mount. The other's wire is thicker, but it plugs (and unplugs) into the handlebar mount. I think the second one is the older style, but I actually prefer it. I suppose the thicker wire adds a few extra grams of weight, but the plug makes it a lot easier to mount cleanly to the bike. If you do a froogle search, you'll see HAC4 cadence kits for either $40-$50 or for $20-$25. The cheaper ones appear to be the old style.

The HAC4+, the one I bought, has cadence. It is the one that can be disconnected from the handlebar mount.

Nice write-up Feanor.
Are you a journalist?

Quoted post said:

Originally posted by Sidi
Nice write-up Feanor.
Are you a journalist?

Thanks for the comliment Sidi! but no, I am not a journalist though I do enjoy writing as a hobby...

Its funny though, after all that I spouted about Heart Rate Monitors and comparing the two that I think are the best, I didn't even scratch the surface of the number of comparisons I could make 🙂

I just didn't want to write a novel (again) 🙂

Have a good one!

Feanor

Quoted post said:

Originally posted by gregk
Wow, Feanor! Thanks for the huge reply!

One more question: Does anybody have both a separate HRM and cyclocomputer just for the sake of having more information displayed at one time? For example, Heart rate on the HRM/ Time, cadence, current speed on the computer. Just curious.

Yep, I have a 710 and still have the old bicycle computer on my racing bike. I specifically kept it on in order to display more information. I think it helps with the motivation.

I typically display HR, time/lap time and cadence/altitude on my Polar and speed, distance on the older unit.

I also bought a second speed sensor for my MTB and only use the polar, usually HR, time and altitude.

A friend of mine recently bought a HAC4, so I will be comparing info soon.

Leon

Well everyone, last night I bit the bullet and ordered the Polar S720i. I can't wait to get it and give it a try!

a follow up questions to the great thread by feanor (and others). i have the polar 520 (which has most of the cycling functions of the 720.)

of course it is lovely to look at, great for HR, etc., but i have NEVER been able to get reliable cadence readings.

i keep the watch on my wrist (to use for other legs of triathlon) and i'm pretty stretched out on aerobars, which means the polar receiver unit is relatively far from the sender near the crank. but actually, even when the receiver is closer to the sender (e.g. when my wrist is near the stem) i still dont get reliable readings.

has anyone else experienced this problem with cadence? is there some way to increase the sender's "transmitting power"?

much obliged for any comments.

Allow me to take a somewhat contrarian line here. If you're using Campagnolo Ergo, the Ergo Brain is the single best computer to use. Not only does it tell you what gear you're in, it also tells you the gear inches, which makes it easier to optimize double changeover gearing. All the standard cycling functions work very well indeed, including cadence.

I love Polar HRM's, but personally don't really like the cycling HRM's. They're unduly complicated, and if you already have most of this data being tracked by the Ergobrain, there is simply no reason to have another set of pick ups mounted on your bike to have the Polar track it as well.

If you're using an Ergobrain, I think a much better HRM choice would be the Polar 610i--their top runner's model. This would give you most of what you'd need to track for competitive cycling, and all you'd need to do would be enter distance ridden in your Polar software--you'd get the distance reading from the Ergobrain. This is the system I use.

Alternatively, you could use one of those new Timex HRM/GPS units--it will provide distance, average speed etc not from a pickup on the bike, but from a small GPS unit. That way you wouldn't need two pickups on the bike. I've heard that these things aren't yet perfected, but they're less expensive than the better Polar units.

Reference mounting the computer or HRM on the stem:

Peter White Cycles sells something called the Chronometro NOB, which is specifically designed for exactly that function.

Here's the link:

http://www.peterwhitecycles.com/accessories.asp

Quoted post said:

Originally posted by tsai
a follow up questions to the great thread by feanor (and others). i have the polar 520 (which has most of the cycling functions of the 720.)

of course it is lovely to look at, great for HR, etc., but i have NEVER been able to get reliable cadence readings.

i keep the watch on my wrist (to use for other legs of triathlon) and i'm pretty stretched out on aerobars, which means the polar receiver unit is relatively far from the sender near the crank. but actually, even when the receiver is closer to the sender (e.g. when my wrist is near the stem) i still dont get reliable readings.

has anyone else experienced this problem with cadence? is there some way to increase the sender's "transmitting power"?

much obliged for any comments.

I found this on the polar website in faq section

http://www.polarusa.com/service_repair/show_faq_con.asp?ID=26

It describes a process to increase the signal strength for the transmitter.

Hey Feanor,

Indeed, great write-up between the Polar and HAC4. I just bought the HAC4+ w/cadence and am struggling with it. It shows less data than my old Vetta V100 HR w/Cadence. I keep a second Cateye Astrale on my bars to show the time and speed. The HAC4 only shows me my HR and cadence. It's too bad you can't see anything else without punching through the buttons. The Cateye also lets me track my trainer rides through winter and bad weather rides. You can't mount the wireless monitor on the back wheel. The head unit just won't pick it up.

I'm looking for info on the Cadence and Wattage functions of the HAC4. I've looked through the manual and can't seem to find a way to call up this information. I've looked on the unit and in the software. I know the wattage is more fudge than fact but it would be helfpful. The Cadence thing is really bugging me as I really rely on that for my training.

Thanks for the help if you can.

Chris