Firmware 4.25-under reporting watts-tilt issue

[NCH1]

Since updating my ibike to firmware 4.25 and inserting a new battery on Friday evening the unit over the weekend consistently has under reported watts on the flats.I know this to be so because I train on the same piece of road, and at about 45km/h I should be doing approx 370 watts and not 80-90 watts (no tail wind). I do not use the rechargeable mount, but I'm wondering whether any automatic tilt corrections were made in this firmware update for those that use the rechargeable mount. The watts displayed uphill however is commensurate with effort, suggesting that it is a tilt issue.

I have tried every known option to rectify this issue:
1. hard reset
2. new cal ride
3. checking wind offset
4. numerous tilt calibrations

All to no avail. However, upon returning home and downloading the files, I have from the pull down menu selected correct for bad tilt. Low and behold the corrected tilt displays wattage figures consistent with perceived effort. Whilst using rollers the ibike in indoor trainer mode seems to be working correctly though

Unfortunately I have no useable files to upload for analysis as data was wiped when I did the on-road hard resets. The downloaded cal ride shows nothing other than a windscaling figure of 2.7 and no other data, for some reason. I have attached this below

Can anyone from ibike or someone with more knowledge than I suggest a fix to this?

Thanks

Nik

[Velocomp]

FW 425 made no changes to anything other than battery voltage measurement. I can't explain your differences, except to say it has nothing to do with 425.

[NCH1]

Ok, thanks John. It did just seem strange that after updating the tilt calibration was off despite setting it prior to training (in addition to setting start elevation and doing the wind offset). Also for the ride yesterday I recorded a -16 average ground wind speed when I downloaded the file.

Nik

[NCH1]

I've just been for a loop around the Bay to see whether tilt calibrations and wind offsets performed at home have had any effect. But no. Again downloading the file I have -16 average ground speed. Whilst on the ride too I gunned it up to about about 46km an hour into a head wind. The reading on the ibike said 70-80 watts output. Something is clearly wrong here, but what, I don't know. It's rather disappointing that all power training will now have to be done indoors on the rollers.

Prior to the ride:
-for ten minutes the ibike (stem mounted) acclimatised
-tilt calibration performed
-wind offset performed
-elevation set

I have attached this file below. Any help would be appreciated. If it helps my Cda is 0.375, windscaling 0.672, aero 0.252, friction 5.790, riding tilt -0.2, crr .0045 and total weight 91kg (200 lb).

Nik

[minus10]

When I had a similar issue as we transitioned to warmer weather here, while I was riding at high speed (35-45 kph) I was seeing low watts on the flat and a big wind offset in the software (-10.6) with little to no wind. I was being credited with a big tailwind when there was none My wind scaling was suspiciously low and yours looks a little low as well. I redid the cal ride with a ton of coast downs in calm conditions and got a more reasonable WS as well as a Crr that made more sense. Power on the road at those speeds now looks a lot more reasonable and the wind corrections post ride are minor compared to before.

One other thing that was odd wad that the cal ride that seems to have fixed the problem also gave a different tilt despite the cal rid being ove the exact same route and the mount not having been changed or moved (-0.3 difference). The only thing I can think of was that this was a new bike with mount and it got 'bedded in' over a month or two going over the dreadful roads we have here in the UK in places.

At these higher speeds it does seem a good WS, CdA and aero are critical to getting a good on the road reading. Post ride, the software seems to do a very good job of correcting any problems and gives good power values but when you're on the road trying to ride to a zone and it's reading low it is problematic. Anyway, cal ride with est fric no and ten or so coasts seems to have fixed my high speed problem.

[racerfern]

Note that when updating to 4.25 the iBike/iAero resorts to Est Aero = YES. So make sure you do a new tilt calibration and check your other settings. For me, the tilt calibration was off and that was easy to fix. Even if the tilt is off, this should only affect the first few minutes of the ride.

[NCH1]

Hi Guys,

Thanks for your suggestions. It is strange that I should now need to do a a new cal ride and numerous coastdowns. The stats I posted in an earlier post are the numbers I have been using for quite sometime and have worked well for me. However, since Friday of last week, power numbers are totally off. Anyway, I'll have to wait until next weekend to do a calride and coastdowns as my week consists of sessions on the rollers. Hopefully that will fix the issue, if not, I don't know, I may have to find an alternative power device as I am in training mode and I have set goals for doing some TT's.

Nik

[fastgreg]

Hi,

I seem to be having a similar problem with the idash. I did a ride yesterday and averaged 33 kph with no wind, out and back - my average watts was 160. I noticed that the wind speed was pretty consistently at -7 and if I look at the wheel/wind graph, the blue extends well down below the white line. My FTP is 307 and everything seems normal when I am climbing, so I think this is a wind offset (?) issue? Should I do a new calibration ride? If I use the 'repair ride for blocked sensor' and leave it at 0 I seem to get watts that are more consistent with what I think I am putting out. Here is the file...


Thanks,

Greg

[NCH1]

I'm just thinking, and I don't know why I didn't consider it sooner as a possible effect on my windscaling, but in the past week I have placed some gaffer tape along both the side edges of the ibike unit (for rain protection). The tape ends at about 3-5 millimetres from the entry to the windport on each side. Is this likely to create turbulence such that it will affect air entering the port and distort the readings?

Nik

[Morocco Mole]

It shouldn't create any significant turbulence, but I have found that sealing the unit with tape does affect the pressure reading and improves my wind scaling and accuracy. You should definitely do a new CAL ride, even if only to get a new wind scaling value. Also, if you are using tape on the iBike, be very careful not to block the small pinhole on the underside of the unit as this is critical to accurate pressure readings.

[NCH1]

Yeah, I will do another CALRIDE on the weekend, thanks mate. I will also check to make sure the pin hole on the undercarriage is not blocked when I get home from work.

Nik

[NCH1]

My Northern neigbour I think was absolutely correct on the issue of the tape affecting the pressure in the ibike. Before riding to work this morning I removed the gaffer tape-problem solved. The readings in the unit were as they should be. I think this just goes to show how sensitive these gizmo's are and I/we shouldn't be complacent about the impact small changes to our bike position and bike setup can have on the ibike.

Nik