Originally Posted by
Random Tandem
2. SRAM i-Motion 3 with coaster brake
This hub appears to be in a working condition, so I just need to lace it into a wheel and then test with a friction shifter (which seems to work with other 3 speed IGHs I have made suffer). Any cautionary advice about poor experience with this type of hub would be welcome (other than I know they were recently recalled due to problems with the grease causing the brakes to no always behave, so I can rely on a front disc brake). If it passes a preliminary function test, I will probably rebuild it with fresh grease in the hope of long service, even if it only has 3 speeds and is cursed with a coaster brake.
This hub was designed to be used with its special iMotion 3 shifter,
which has a different pull from the SRAM/Sachs T3 and DualDrive hubs (and I hardly need to add different from Shimano and Sturmey 3s).
https://www.sheldonbrown.com/cribshe...able-pull.html
Further, unlike Sturmey-Archer 3-speeds, the SRAM iMotion 3 is a low normal and there is no 'alignment'. You set the proprietary (cheapy, plasticy twist) shifter to barely be able to pull the hub into 3rd (high) gear and the shifter takes care of getting the internal mech of the hub properly and securely into gears 2 and 1 (low).
Disassembly of the iMotion 3 begins on page 36:
https://www.sram.com/sites/default/f...glish-reva.pdf
These are lovely, innovative little hubs, with all prime number tooth count gears and an asymmetric internal arrangement (9 plutoed planets!). The early models were manufactured in Germany before production was moved to Taiwan. They were discontinued two years ago.
There is no known source for spare parts. It's fairly easy to 'un-coaster brake' them.
Finally, any thoughts about drilling each of these hub shells to add an oil port to allow them to be run "wet"?
Bon chance drilling that SRAM hubshell, mon ami.
BTW, with a coaster you'll want to use a 'high temperature' grease.