How to get more consistent power readings

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Roadiemark
Posts: 47
Joined: Tue Jan 18, 2011 8:19 am

How to get more consistent power readings

Post by Roadiemark »

Hi

ok been using the ibike dash since January this year and I have learnt a lot about my fitness and my training, road faster TTs and even beat my PB on a 25mile TT using the ibike dash.
getting more consistent power readings have been plageing me for a mouths but finally I have solved my problem this is what I have found, first I live in the UK and the road here are not always good very bumpy and uneven, this curses the phone booth to bounce or flex up and down which in turn makes the iPhone’s tilt sensor not read it’s like it goes into brown out or shut down! In turn makes your power reading drop off!!!! The harder you pedal the lower it gets because it bounces more. On inspection once I figured out what was going on is that the phone booth flexes on its mount there is no slop on the mount just flex.
my solution has been too support the front of the phone booth on my stem to take out this bounce, I have used an old Garmin mount with a layer of thin foam and a rubber band to hold it down, it can still flex if you hit a big pot hole I didn't want it to ridged and brake, the result has been that on the same stretch of road that is bumpy and previously the power readings would drop off now they stay at the level I would expect to see :D

Take a look at the photos to see what I have done.

Mark
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rcmaps
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Re: How to get more consistent power readings

Post by rcmaps »

Great idea!
Thanks for sharing this tip.

There is a stretch of road on my daily commute that turns from smooth asphalt into rough chip seal road. I can almost guarantee that the power drops by at least half or less even though my cadence and pedal pressure is the same or even a little harder. This is because of the slight "bouncing" on the very rough chip seal.
I'll give this idea a try soon to see whether that changes.
Velocomp
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Re: How to get more consistent power readings

Post by Velocomp »

Very clever!
John Hamann
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Re: How to get more consistent power readings

Post by rcmaps »

I found a piece of Staedler eraser - cut a small piece off the end and managed to quite easily "wedge" this between the bottom of the iDash case and my stem that dampens the vibrations.

Fits perfectly and firmly without any mounting or zip ties.

Went on my regular commuting stretch of road and sure enough the expected power dips from smooth to rough part of the road disappeared! :D

Thanks for the tip again. :mrgreen:
aaduarte
Posts: 16
Joined: Tue May 03, 2011 11:30 am

Re: How to get more consistent power readings

Post by aaduarte »

So that's a must for mountain biking!

Thanks for sharing it,

Also I'll post at the feature requests, if its possible to adjust the crr if the ibike is sensing a lot of bouncing. Because it's not the same going in smooth road than bouncing on mtb. Like a MtB mode, that can change the crr based on the vibration.
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