I swapped out the SRAM PG-1230 Eagle (11-50, 12 speed) that came with my Powerfly 9.7 with an Eagle GX (10-50, 12 speed) and I notice some weird inconsistency with the motor, the top 5 gears of the GX are the same as the PG, -1 tooth per cog. However, it feels as if the motor doesn't quite know how to handle these gears: Assistance is not as smooth as it was with the original cassette and I also notice some weird intermittent vibration through the crank while in top gear.
Are the bosch units in these bikes SPECIFICALLY tuned to the gears that come with the bike and changing any of them throws the motor out of sync?
I have read in some forums that the motors have a specific wind per application and some people have experienced issues when tinkering with gears and such.
I have seen on the Trek site that the new Rail 9.9 has a rear cassette with the same gears as this Eagle GX I bought, (which makes me think there's no reason why I can't use similar hardware) but I wonder if the control unit and/or motor on the Rail is tuned specifically for that set up.
Is there an "ECU reflash" available? perhaps a Bosch technician can access the Purion unit and configure it to a new set of gears?
Thoughts?
Are the bosch units in these bikes SPECIFICALLY tuned to the gears that come with the bike and changing any of them throws the motor out of sync?
I have read in some forums that the motors have a specific wind per application and some people have experienced issues when tinkering with gears and such.
I have seen on the Trek site that the new Rail 9.9 has a rear cassette with the same gears as this Eagle GX I bought, (which makes me think there's no reason why I can't use similar hardware) but I wonder if the control unit and/or motor on the Rail is tuned specifically for that set up.
Is there an "ECU reflash" available? perhaps a Bosch technician can access the Purion unit and configure it to a new set of gears?
Thoughts?
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