Power Meter Recomendation

Polars are good except when you're in the big ring and larger than a 21. Usually have good watt reading in the workout range of 17 to 22 mph. That's why I have 4 of them. Only bad thing is the 5 sec recording. So my ultimate bike will have an ergomo pro. NO Powertap because I've seen so many threads complaining about their problems. SRM is just too expensive and I'm not a hard core racer.

kopride said:

Sorry if this is an old and tired topic. I just read the geek comparision review so it appears as though it is a choice between the Powertap or SRM. From my perspective, having a spare wheel makes more sense than shelving a brand new crankset, so powertap has some economic appeal. Assuming that the tie will go to Powertap for this reason alone, is there any compelling reason why I should choose the SRM? Should I wait for the brand new (2.4) to become widely available, or can I get away with an older cheaper design? I also really like my Shimano computer, which is integrated in my handlebars, is that also now something that will be relegated to the shelf?

There are lots of differences between the PT SL/SL2.4 and SRM Pro, some of which are subtle. What's best for you is obviously a value/cost decision that only you can make, but here are some differences (and non-differences), to be weighted any way you see fit.

As to accuracy, I think it's a wash other than for very short duration efforts. The PT recording frequency (1.26s for the models prior to the PT SL2.4 and 0.63s for the SL2.4 IIRC) can be a non-trivial constraint for analysis of sprint efforts, but should be a non-issue for all other efforts.

As to display options, I would give the edge to the SRM, at least for intervals.

As to flexibility of using different wheels, it's about a wash economically because it's unlikely that the multiple PT hubs required for multiple wheels will exceed the cost of an SRM Pro. As to using multiple frames (e.g., road & TT), I'd give a slight edge to PT, especially the SL2.4, but it's not difficult to switch the cranks.

As to keeping the systems "in tune," I'd give the edge to PT but it's not a big deal to keep the SRM in tune.

As to long-term maintenance, I would have given the edge to the SRM prior to availability of the SL2.4 (due to moisture problems only), but I think it will be a push with the new SL2.4 due to changes in its waterproofing treatment.

The bottom line: they're both great systems and I think you will enjoy either one.

kopride said:

Sorry if this is an old and tired topic. I just read the geek comparision review so it appears as though it is a choice between the Powertap or SRM. From my perspective, having a spare wheel makes more sense than shelving a brand new crankset, so powertap has some economic appeal. Assuming that the tie will go to Powertap for this reason alone, is there any compelling reason why I should choose the SRM? Should I wait for the brand new (2.4) to become widely available, or can I get away with an older cheaper design? I also really like my Shimano computer, which is integrated in my handlebars, is that also now something that will be relegated to the shelf?

Alot of differences.

The only one huge difference you want to keep in your mind is the reliability factor. SRM is more reliable than the Powertap plus you may have to make few changes to the powertap to withstand rain.

nrhorwitz said:

Alot of differences.

The only one huge difference you want to keep in your mind is the reliability factor. SRM is more reliable than the Powertap plus you may have to make few changes to the powertap to withstand rain.

Are you making this statement based on your personal experience? Because I have >10K miles on my PT SL and have never had any moisture problems. I'm aware of a few who have had moisture problems with pre-SL2.4 PTs, but I know many other PT users who have never had such problems. In fact, the only problem I have had is with frame vibration and that was easily and permanently solved. I really don't know that I would label reliability as a "huge difference." But, hey man, if you've got the hard evidence to back up your assertion, go for it.

RapDaddyo said:

Are you making this statement based on your personal experience? Because I have >10K miles on my PT SL and have never had any moisture problems. I'm aware of a few who have had moisture problems with pre-SL2.4 PTs, but I know many other PT users who have never had such problems. In fact, the only problem I have had is with frame vibration and that was easily and permanently solved. I really don't know that I would label reliability as a "huge difference." But, hey man, if you've got the hard evidence to back up your assertion, go for it.

I am lucky enough to have a PTSL and SRM Pro. Both very good products. Other than the minor vibration deal (as RDO mentions -- easily remedied) that some folks have had with the PT, its been rock solid and just as reliable. Set up properly, it's also very water resistant. A couple of random, minor observations: 1) the SRM does seem a bit more "robust" in terms of materials (but it should given the price ...); 2) both take me about the same amount of time to swap over to a different frame; 3) the SRM interval function is a bit more intuitive and easy to use; 4) when traveling, the SRM is a pain at times b/c you need a PC to clear the memory.

Setting aside the cost, my own bottom line is that if I were buying a PM right now I would get a PT again if I didn't have any nice wheels. Get a nice solid race wheel build and be done with it. If I had a rack full of different wheels I would go with the SRM -- once I started to train and race with power, I didn't want to ride without my meter and download every file.

kopride said:

I also really like my Shimano computer, which is integrated in my handlebars, is that also now something that will be relegated to the shelf?

I have a PowerTap Pro and use it in conjunction with my Shimano FlightDeck computer. I know it probably seems like overkill, but I love having the gear info of the FlightDeck. Plus, since I usually have the FlightDeck set to display speed and cadence, I have my PowerTap set to display power, heart rate and elapsed time (or interval time when in interval mode).

So in short, I'd keep the flight deck on and use both. The other benefit is if you can't ride with your PowerTap wheel, you'll automatically have a back-up computer to at least log ride time and miles.

JTE83 said:

Polars are good except when you're in the big ring and larger than a 21. Usually have good watt reading in the workout range of 17 to 22 mph. That's why I have 4 of them. Only bad thing is the 5 sec recording. So my ultimate bike will have an ergomo pro. NO Powertap because I've seen so many threads complaining about their problems. SRM is just too expensive and I'm not a hard core racer.

That sounds like a setup problem on your Polars...make sure the chain is never further than 25 to 30 mm above the sensor in your largest USEABLE chainring - largest cog combo. I tend to shade mine closer to 25mm max, even if it means a little bit of rubbing on the case in some of the small ring - small cog combos (which I rarely use anyway).

I agree on the 5 sec recording...I can't wait to see the new Polar CS600 version with the faster recording rate.

BTW, I'm not completely *sold* on the ergomos either...too many reports of discrepancies between them out of the box for people who have other PMs to compare them to (like a PT).

For the OP...it's tough to beat a PT for "bang for the buck" especially if you use a cover for TTs. One of the downsides IMHO is the lack of an altitude sensor. That's not a *necessity*...but it sure is NICE to have, even if it's just to make looking at power files easier. The SRM doesn't have one either. So far, it's just Polar and Ergomo with altitude. Also, it's too bad Shimano hasn't gotten off their collective rears and come out with a PM to integrate into their computer. They had a BB based PM patent issued to them over 3 years ago. It's a pretty clever concept too, with chain reaction forces at the BB bearings measured by piezo sensors.

Tom Anhalt said:

For the OP...it's tough to beat a PT for "bang for the buck" especially if you use a cover for TTs.

I'm awaiting some wind tunnel test data. If it turns out the way I think it will, the unavailability of a PT disc may soon be a non-issue. More later.

RapDaddyo said:

I'm awaiting some wind tunnel test data. If it turns out the way I think it will, the unavailability of a PT disc may soon be a non-issue. More later.

Hmm...could it be a PT hub laced inside a Blackwell 200?

I think I'd still prefer a regular rim with a cover if I went PT....more "dual use" capability 😉

I like the small ring small cog combo, and it's not good to use the big ring big cog combo so I didn't setup my Polars for that. If Polar only had 1 sec recording for up to 8 hrs I'd be happy and just stick with it. I want my top bike - the CF Soloist to have an ergomo pro but maybe I should just temporarily run a Polar on it. Sure missed a $173 ebay auction on one I let go by.

It seems like a lot of serious power meter guys dismiss the Polars. I just think it runs inaccurate a little when the chain is far from the sensor. Maybe I should give it a close look and test run.

An interesting thing is that I have 4 good bikes with Polars and I'd like to analyse my data for which one is the best bike based on highest speed per watts.

I was [censored] that Polar came out with better HRMs than the S720i but never improved the data recording rate and total data capacity.

Thanks, all. When my wife asked me what I wanted, I figure If I can't beat you power geeks, I might as well join you. Also, my crane creek wheelset is ok, but I already had a rear bearing go, so I figure a spare wheelset is always nice. Looks like the new PT2.4. if I can find a dealer with one in stock. What kind of bearings are in the new PT hub? Are they just regular cartridge bearings, or cone and hub? And, I will probably be super geek with my Flight Deck and power computer. Throw on my Polar HRM watch and I will be the "king of all bike geeks."

Tom Anhalt said:

Hmm...could it be a PT hub laced inside a Blackwell 200?

I think I'd still prefer a regular rim with a cover if I went PT....more "dual use" capability 😉

Unfortunately, rim covers are not legal for use in any UCI sanctioned event or event run by Federations that use UCI rules (e.g. like here in Australia). They are legal under USCF regulations AFAIK as they have not aligned to UCI rules.

Alex Simmons said:

Unfortunately, rim covers are not legal for use in any UCI sanctioned event or event run by Federations that use UCI rules (e.g. like here in Australia). They are legal under USCF regulations AFAIK as they have not aligned to UCI rules.

True 'dat! I guess that makes my Polar a more desirable option for someone who needs to worry about the arbitrary (IMHO) UCI rules 😄

Tom Anhalt said:

True 'dat! I guess that makes my Polar a more desirable option for someone who needs to worry about the arbitrary (IMHO) UCI rules 😄

Not for long (I think).

One post in the string mentioned the altitude function in the Ergomo. I noticed several riders in my area using Ergomos in the last few months. While the OP was torn between the SRM and PT, why avoid the Ergomo? Any beefs from anyone?

Max358 said:

One post in the string mentioned the altitude function in the Ergomo. I noticed several riders in my area using Ergomos in the last few months. While the OP was torn between the SRM and PT, why avoid the Ergomo? Any beefs from anyone?

I love mine. Some folks have complained about calibration problems, but I haven't experienced any problems there. The original Ergomo lacked some key features like reporting average power during intervals but the current Ergomo Pro has included that and a host of other features including some that are unique like real time TSS, IF and NP reporting in the Pro Power display. I didn't want to replace all my wheels, couldn't afford an SRM and wasn't wowed by the Polar so I chose the Ergomo and have no regrets.

-Dave

daveryanwyoming said:

I love mine. Some folks have complained about calibration problems, but I haven't experienced any problems there. The original Ergomo lacked some key features like reporting average power during intervals but the current Ergomo Pro has included that and a host of other features including some that are unique like real time TSS, IF and NP reporting in the Pro Power display. I didn't want to replace all my wheels, couldn't afford an SRM and wasn't wowed by the Polar so I chose the Ergomo and have no regrets.

-Dave

Do you mind if I ask how you've checked your calibration?

Tom Anhalt said:

Do you mind if I ask how you've checked your calibration?

The ostrich method is very popular among Ergomo owners. 🙂

Tom Anhalt said:

Do you mind if I ask how you've checked your calibration?

Well not with a dynamometer🙂

I got hooked on power meters by riding a friend's PT equipped bike and did the standard 20 minute tests, sprints and such. My best efforts on the Ergomo match very closely allowing for drive train power losses. For instance my best 20 on the Ergomo was 9 watts higher than my best 20 on the PT with the efforts less than a week apart from each other. I also ride ergs at the gym and my current intervals match very well in terms of RPE and ability to complete a given set at a given power level. Nope, it's not calibrated in a bureau of standards sense but I trust the numbers and I don't notice any variability from ride to ride. So as far as I'm concerned the calibration seems quite good. Whether 300W on mine matches 300W on someone else's isn't a big concern, that's what races are for.