So here are the preliminary findings regarding the possibility of adapting a Kindernay IGH to the LMX 64.
After getting more info from Kindernay on their current hub dimensions and future product, as well as more data on LMX dimensions from the kind people on the forum, it seems adapting a Kindernay hub may actually be reasonably easy.
Below are the details of my investigation, feel free to point obvious flaws I may have overlooked
Kindernay info:
https://kindernay.com/gallery/
• Currently they have a short and a long version of the hub
• They have three different shifter width and three different left cap width, allowing them to create three dropout sizes with the short hub (138 / 142 / 148), and two for the long versions ( 190 / 197)
• The long hub is the same as the short one, except for an extension of the sprocket and shifter axis on the right side, changing the chainline from 48.5mm for the short versions (135/142/148) to 76mm for the long ones (190/197).
• The way they keep the wheel centered over these, is by having two different wheel mounting cage sizes across the whole assembly.
• There is a 170mm version of the Hub in the work, with a potential 66mm Chainline
LMX info gathered (to be eventually precisely measured or confirmed with LMX):
• 5mm between left dropout and disk outface
• 16mm between disk inface and sprocket inner ring outface
• Motor sprocket outer ring offset from inner ring (estimated around 4mm)
• Motor chainline of 57.5mm (not sure if chain or belt)
• Pedaling chainline from LMX SEMPU BB spec 65mm (also measured at 70mm)
• Dropout of 170mm
Using Kindernay future 170mm hub.
That hub does not exist yet, but based on the current ones and info gathered with Kindernay, I extrapolated its dimensions below
Based on that, it appears that a fairly simple adapter could be made to receive the disk and the Motor rear sprocket (chain or belt), if we lose the Motor sprocket freewheel.
• A single small adapter holding sprocket and disk, 7 screws going through disk, adapter, Hub and into the Cage
• Motor sprocket mounted on the outer part of that adapter using existing sprocket holes pattern.
• Cut the torque plate to a circle fitting in the adapter inside diameter (about 84mm) with two holes for two torque screws possibly going into the left dropout recess (if that does not compromise it).
• A possible modified left side cap to complete the dropout width and with holes to support the Torque screws going through.
Note 1: A version of the adapter supporting a motor sprocket Freewheel could be envisioned, if a freewheel bearing existed in a large inside diameter (like 120mm or so) which I am not sure they do. If such a bearing freewheel existed, it would also require machining a new Sprocket
Note 2: Using the Kindernay short hub, we could shift the hub to the right and have a longer space on the left where an adapter supporting the freewheel would only require one with a 60mm internal diameter or so, which may exist.
But that would be significantly more labor intensive, requiring an extension of the torque arm, a more complex adapter with probably some bearing support over the torque arm extension. I have some principle drafted, but would need to know more about the type of freewheel required.
Questions regarding the loss of Motor Freewheel:
• Apart for some drag if pedaling on a dead battery or on PAS zero, as well as going downhill without the motor, is there more drawbacks or potential issue from losing the motor rear sprocket freewheel?
• How bad would that drag be?
• Could that possibly allow regen to be implemented?
Below some 3D views of the various pieces
Folder link:
https://onedrive.live.com/?authkey=%21AFV6HsrOgAQ1tbc&id=4BE668230430EFDD%212417&cid=4BE668230430EFDD