Jancouver

TT power VS climbing power (or power output riding road bike)?

Whatever I do, I cant achieve the same power output on my TT bike that I can do on my road bike. The difference is about 15% or even 20%. Different muscles being used? So was thinking about trying a different TT position by moving my saddle & bars lets say 2cm back. Would moving my saddle & bars make sense? My current position was dialed with two fitters, traditional & Retul. Its pretty aero but I just feel (even) weaker than on my road bike.

HMF

The power reading on my wired powertap cuts out frequently. The sensor is as close to the hub as I can get it. It doesn't affect the power file though. Any suggestions?

waterrockets 

Is the shark fin pointing up or down? Up puts the sensor closer to the hub.

HMF

Like that (not my bike)

kleinboogie

I wish I knew. I have 10% more power in my TT position. I'd love to have my TT power on my roadbike which I try to replicate by being in the drops on hard effort points like a breakaway and climbing but can't quite get there. My theory was my upper body weight provides more resistance so I push down harder. If you find out let us know. GL

waterrockets 

I'd try it on the chain stay instead of the seat stay. That should move the receiver closer to the axle. Might help.

Not likely for threshold power. The difference in pedal force is not that great for 30(?) Watts of power. If your cadence is higher on the TT bike, it will be minimized further.

It's got to be position. What's the spindle -> saddle tip -> shoulder angle in the two positions? You might actually be too acute in the road position if your saddle is further back on the road bike.

valygrl

Is the cadence that the Powertap SL+ (ANT) sends to Garmin inaccurate?

From today's ride:
min max avg
Cadence: 30 218 97 rpm

I know my avg. cadence from the Garmin's cadence sensor is usually in the high 80's, and I saw peak cadences for the shorter intervals in the 150-200 range, which I know is wrong. Is there a setting? I don't have the garmin cadence/speed sensor mounted on this bike, it's on my other bike, and I don't want to move it over if I don't have to.

HMF

Just an FYI update on my issue. I was able to get it further down the seatstay, so that helped. Also, I changed the averaging to 10 seconds. I think that if the head unit is getting too many zero readings it cuts out, but if number of zero readings is small compared to the 'n' in your average, then it can work around it. This is entirely speculative, but that's how I'd design it. I also like the 10 second averaging much better when it comes to pacing.

waterrockets 

Glad you got it worked out.

+1 on the 10" averaging. It's either that or interval average for me. Depends on my mood.

brian416

When I was riding with a wired powertap and my Garmin, the powertaps cadence numbers would generally vary +-10 rpm from the Garmin's cadence sensor, but the average cadence for the whole ride was usually within 1-2rpm

gfactor

Another thing to try is replacing the batteries in the hub.

I_Like_Bike

How useful is power data with little understanding of how to use it?

How hard is it to learn?

Is it, when used properly, the best place to spend money with the end goal of getting faster?

I want one, but feel like I do not use me HR meter enough to justify the purchase of a PM. I feel like HR is just something that I look at when I am about to get dropped, or to insure that I go easy on recovery rides. After the ride analysis is laking though. Will a PM, WKO+ and the training with power book give me better after ride analysis?

Thanks!

waterrockets 

Start reading the Power 411 to get started.

I didn't use HR much before my PM either. The PM is totally different. You do need to dig into the data though. You either need to hire a coach to handle the data for you, or you need to bone up on it and take up self-coaching as a hobby. I did the later with much success, but you'll plateau in your self-coaching abilities at some point, and a good coach can take over from there if you want to continue progression.

ridethecliche

You have to make tradeoffs. Are you faster on the TT bike than the road bike? If so, then you'll adapt to the position. If after you've adapted, you're still slower then you're going to need to figure out what it is about your road position that helps and try to go from there.

20% is really really really steep.

currand

I'm fairly certain that there is no correlation between the data that's stored and the data that's displayed. Meaning, the PT always records the data in 1(ish) second increments and then uses that data to display. So in theory if you are still getting zeros your average power would either be drug down or, possibly, the zeros would be throw out. Depends on wether you set the PT to count zeros in averaging.

ericm979

Not much. It's a pretty computer for impressing random freds.
Buy the book. Read it. If you finish it thinking of all the great things you can do with the data you'll get, then buy a PM. If you put the book down halfway through because you are bored, then don't get the PM- you won't be using it effectively. Or get the PM and a coach who will look at your data.

BTW you can also use the open source GoldenCheetah for data analysis.

aham23

running a garmin 500 with quarq power. i got the 500 in April, so it is sorta new to me. coming from a 305 then 705 i am use to Garmin's crazy calorie calculations. training with power the last 2 years i only pay attention to KJ anymore. messing around with some files and i noticed the calories burnt number for the 500 is typically 300 to 500 LESS then the KJ number. seems odd to me as i think it would be the other way around. anyone else notice that?

yes, i am bored and at work. later.

currand

I think the Calories burned is a Garmin formula (based on heart rate or speed or weight or some combination of them). kj is based on power data. For some reason they don't just copy the data from kj to Calorie.

JohnKScott

Yep. Same here. Looks like, depending on the variability of the workout between 10-20% lower then the KJ for me.

GirlAnachronism

Funny, the calorie number I get from Garmin (500 w/PT) is usually slightly higher than kJ.

caloso

My calorie numbers tend to be 10-15% lower than the kj numbers. I thought it might have something to do with the fact that most of my riding is flat and so I'm usually pedalling. Maybe it's just a Garmin thing.

grwoolf

It's limiting, but you can still get significant value. Power numbers are great motivation when riding alone, particularly during high tempo type rides where you might get a little lazy without a good measuring stick. It's also a good way to measure training load/stress balance, which can keep you from getting burned out before you dig a deep hole. You'll get much more benefit if you understand the bigger picture.

Read the book. If you can follow it and can't wait to get a powermeter after reading, go for it. If you're confused, you might need some help from a coach or friend before jumping in.

I feel it was the "best bang for the buck" cycling purchase I've made with the goal of getting stronger, but nothing is going to replace the hours and work on the bike.

This summer, I've really been out of training mode, focused on races and fast group rides as much as possible (I'm a new racer trying to learn tactics, etc.). I'm still pretty obsessive about reviewing my power numbers post ride/race, but the power meter is more about understanding my weaknesses to shape future training plans than actually used for training right now. I'm planning to get back to a more structured program in the fall when racing tapers off and I'm down to one group ride per week.

shovelhd

The best bang for the buck training purchase in support of increased fitness was my used Kurt Kinetic. A good winter training platform, be it a high quality trainer or set of rollers, is hard to beat in this category. #2 would be the computer, #3 would be the Powertap wheel.

aham23

i should have clarified that i understand the difference between estimated Calories burnt from HR devices and KJ. when i evaluate efforts i just use the pure KJ number.

i was under two assumptions; 1. Garmin fixed their problem with the new models. 2. If different the Garmin # would still be higher.

interesting to see most others see the same thing, Garmin lower. later.

jgg3

I forgot to turn off my Garmin 500 after the Housatonic Hills RR today, and drove home with it in the trunk, happily recording my car trip. Now I have a bunch of non-power datapoints that mess up averages and stuff. The maximum speed is pretty impressive, though, especially how long I held it.

In WKO+, how can I delete the parts I don't want? The obvious attempt to select and hit the delete key doesn't work. Nor does making a range and delete range, which of course just deletes the range, not the data.