I continued my investigations initiated during the
Amic pass time trial on the mechanical performance of the transmission.
Depending on the location/alignment of the Drivetrain performance chain, is it better
to favor
The small or large chainring for equal development?
For this I used a powertap, my SRM and I also
compared everything in my test climb against the theoretical calculation . The powertap being
there to make a duplicate measurement with the SRM against the theory and also
to see if it can detect losses during extreme chain crossings
against perfect alignment. So I started with 3 telegram data Drivetrain performance climbs around 70
rpm with the chain in the
following configurations:
Crossing 50×25
Aligned 36/17
Modified / aligned 50×25
50×25 aligned
The results show that the worst configuration, as
expected, is the 50×25 crossed chain configuration. We
would dissipate almost 1% (2.2 watts towards 250 watts) in the transmission
compared to a 36/17 aligned configuration if we believe the powertap or
even 2 watts if we compare the SRM result to a
theoretical calculation of the climb. So very similar results.
The most surprising thing comes from the result
modified cassette on which the fact of being able to switch to a large
crown and pinion while being aligned does lead generation strategies to implement in 2025 not improve the efficiency. It is very
small as a difference with the
36/17 configuration (0.5 watts of loss) but it is not going in the right direction! Indeed
we could expect with everything we read or ‘they say’ that switching to larger crowns for equal development was
beneficial… I did not try to do
additional climbs and I admit that it would have been necessary malaysia numbers list to double the measurements
as I do all the time to confirm this result. But this time the
powertap reinforces the conclusions.