Garmin Vector Delayed AGAIN

Murph100

Brim Brothers FTW !!!


http://www.bikeradar.com/road/news/article/garmin-vector-power-meter-release-date-pushed-back-33677/

Lumen

Reading reports from Look power pedal users on the Wattage group hasn't boosted my confidence in pedal based systems.

On the other hand, my newly-arrived Power2Max cranks don't fill me with confidence either, with users reporting big drifts often (but not always) caused by temperature changes.

SRMs are fine as long as you don't mind sending them off for battery changes and borking your training load stats.

And then there are the bearing problems and wheel-dependency of the Powertaps.

If only Quargs were cheaper...

morana

Lumen wrote: »

Reading reports from Look power pedal users on the Wattage group hasn't boosted my confidence in pedal based systems.

On the other hand, my newly-arrived Power2Max cranks don't fill me with confidence either, with users reporting big drifts often (but not always) caused by temperature changes.

SRMs are fine as long as you don't mind sending them off for battery changes and borking your training load stats.

And then there are the bearing problems and wheel-dependency of the Powertaps.

If only Quargs were cheaper...

I change the batterys in my srm! They cost a tenner so i usually get 2 or 3

Lumen

morana wrote: »

I change the batterys in my srm! They cost a tenner so i usually get 2 or 3

http://www.srm.de/us/support/faq/maintenance

"The PowerMeter battery is not self-replaceable. You will need to send it to the Service Center for replacement. ATTEMPTING TO REPAIR IT YOURSELF WILL INVALIDATE THE WARRANTY, and could cause permanent damage to your PowerMeter."

Murph100

If only SRM was cheaper ...

morana wrote: »

I change the batterys in my srm! They cost a tenner so i usually get 2 or 3

Beasty

A Quarq died on me last week - bought it last March - pleased to discover when I contacted Cyclepowermeters.com that they have a 2 year warranty

Delay on the Garmin is very frustrating, but I think Tunney predicted this last Autumn. Really don't fancy going with the Polar - maybe I will have to think about SRM ...

Chips Lovell

Why does Power2Max suffer from temperature drift, while Quarg and SRM don't?

Lumen

Vladimir Kurtains wrote: »

Why does Power2Max suffer from temperature drift, while Quarg and SRM don't?

They all do.

The specific issues reported with the P2M are:

1. It drifts my more watts-per-degree than the others.
2. It drifts even when the temperature has not changed.
3. The auto-zero is automatic and happens whenever you freewheel.

I'm not sure (3) is really a problem in itself, because while freewheeling up a long climb is awkward, so is backpedalling (which is how you do it with the Quarq). The problem is that in combination with (1), if you don't zero it then the drift is worse, and there is some dispute as to how accurate a freewheel-based zero procedure is, compared to either zeroing while backpedalling or manually through the head unit whilst stopped and unclipped.

What makes this difficult is that there appear to be large variations in "reliability" (of the data) between individual powermeters from both P2M and Quarq, with some users who have multiple units from the same manufacturer reporting different behaviour, so that one person's Quarq may be better or worse than another person's P2M.

Honestly, it's enough to turn anyone into a luddite.

Chips Lovell

How do you know if it needs zeroing? Does the power output displayed go up or down compared to perceived effort?

How do you zero an SRM?

Are we talking about a technology here that is still going through teething troubles or are these issues relatively minor in the greater scheme of things, i.e. are somewhat inaccurate readings still more useful than training on HRM or perceived effort?

Beasty

Presumably part of the drift is explained by friction within the unit itself. So on a day like today when the temperature was only a couple of degrees throughout the morning commute, as the ride progressed the unit warmed up. I tend to backpedal a few times in the morning as I suspect the impact is more marked from a "cold" start

Lumen

Vladimir Kurtains wrote: »

How do you know if it needs zeroing? Does the power output displayed go up or down compared to perceived effort?

You generally zero a power meter when the temperature changes, which means at least once per ride. If you keep your bike indoors you must wait 10-15 minutes for the cranks to reach ambient temperature before zeroing.

With my Quarq, if I feel during a ride that the watts are off I just backpedal to re-zero it.

Vladimir Kurtains wrote: »

How do you zero an SRM?

I think all Ant+ power meters can be zero'd through the head unit. In a Garmin 500 this involves going through eleventy million menus to the 'Calibrate' function. But it's not actually a proper calibration of the "slope", it's just setting the zero point, i.e. the torque reading that represents no force on the pedals.

SRMs are calibrated (from a slope perspective) by hanging known weights from the pedals or chainrings.

Quarqs used to be factory-only slope calibration, but you can now do it through a iPhone dongle, which I have but haven't used.

Dunno about the others.

Vladimir Kurtains wrote: »

Are we talking about a technology here that is still going through teething troubles or are these issues relatively minor in the greater scheme of things, i.e. are somewhat inaccurate readings still more useful than training on HRM or perceived effort?

There are many simple ways to measure training effort without a power meter, but they don't tell you anything about training effect.

With a power meter you get objective feedback about training progress that doesn't require using a timed course, and you get pretty graphs like this which show objective progress over time (the gap in the middle is when I sent back my PM after I snapped the crank bolt).

Of course you could just time a ride up a big hill once a month and use HR for training effort, but a PM gives instant feedback/gratification wherever your cycling takes you.

I'm sure the technology will improve, although I don't expect it to get much cheaper any time soon given the engineering challenges involved. I do think most power meters are accurate enough to be very useful.

Murph100

Dammit Lumen, I was so close to getting the Power2Max until you set the seeds of doubt !

I might as well stick to the bloody Tacx for testing and HR on the road for intervals. :rolleyes:

Lumen

Murph100 wrote: »

Dammit Lumen, I was so close to getting the Power2Max until you set the seeds of doubt !

I might as well stick to the bloody Tacx for testing and HR on the road for intervals. :rolleyes:

I've saved you loads of money. You're welcome. :pac:

Seriously, I've probably spent far too much time on Wattage. I'll post up a review when I've got the P2M fitted and used it a bit.

mloc123

Lumen wrote: »

Murph100 wrote: »

Dammit Lumen, I was so close to getting the Power2Max until you set the seeds of doubt !

I might as well stick to the bloody Tacx for testing and HR on the road for intervals. :rolleyes:

I've saved you loads of money. You're welcome. :pac:

Seriously, I've probably spent far too much time on Wattage. I'll post up a review when I've got the P2M fitted and used it a bit.

I have two powertaps at the moment, one has been sent off twice for repair.. Free both times. I had considered a p2m a couple of months back but went with the second pt instead.

As far as price, reliability and accuracy goes I think PT is a decent all rounder. That said I now have a SRAM s900 crank and may pick up a p2m over the next few months. The drift puts me off.

Diarmuid

Unless you spend most of your time on the turbo (or do TT's from your front door), you're not even going to notice the fact that it auto-calibrates.

Bambaata

Lumen wrote: »

I've saved you loads of money. You're welcome. :pac:

Seriously, I've probably spent far too much time on Wattage. I'll post up a review when I've got the P2M fitted and used it a bit.

Ive my p2m a decent time now and can report that yes temperature does effect it this is very easy to solve. Ive also found that after about 40mins i dont need to do it anymore. Cycling outdoors this isnt an issue at all as we all inevitably freewheel for a few seconds here and there. Indoors on the turbo is the only issue and a few stops in the opening 40mins solves it. And by stops i mean just 5seconds of not pedalling which isnt long. Ive been more than happy with mine.

25sean

Coming in with some very general questions here on this..

considering going for power to train with, is it really that much better? any links/reading on the subject?

powertap seems to be the easy/most affordable option.. ebay best for prices?

murph, you have power on your turbo, something like this ?

thanks in advance...

vigos

Murph100 wrote: »

Brim Brothers FTW !!!


http://www.bikeradar.com/road/news/article/garmin-vector-power-meter-release-date-pushed-back-33677/

further update from them here:

http://www.brimbrothers.com/2012/05/steady-as-she-goes/

although still no sign of when it will be ready...

sconhome

Beasty wrote: »

Really don't fancy going with the Polar - maybe I will have to think about SRM ...

Any particular reason why you'd not go with Polar?

*disclaimer - I have a set.

Beasty

amphkingwest wrote: »

Any particular reason why you'd not go with Polar?

*disclaimer - I have a set.

Not Ant+, and I don't particularly like the Polar computers - much prefer Garmin and Joule