In order to determine if eeWings will fit your mountain bike we need to focus on two things: 1) BB Shell Width (Spindle Clearance) and 2) Crank Arm/Chainstay Clearance. For both of these measurements it helps to refer to the eeWings MTN User Specification:
BB Shell Width (Spindle Clearance)
The usable spindle range on the eeWings MTN is between 93.25mm and 98.25mm. This takes into account the Preloader-and its full range of adjustment--and the 1.75mm Spacer that is included with eeWings. To determine if the spindle is going to be long enough you need to take into account the full width of your bottom bracket (Shell+Bearings).
Example: A 73 mm "Threaded" Bottom Bracket shell used with one of our Hellbender Bottom Brackets will come out to a total width of 95mm (73mm Bottom Bracket Shell + 22mm of added width from the Bottom Bracket). This is perfectly within the usable range of the eeWings MTN spindle.
Crank Arm/Chainstay Clearance
The second measurement is to determine if the eeWings will clear the chainstays of your bike. The eeWings were optimized for Boost Hub Spacing but they can be used on many Super Boost bikes. Using the measurements from the figure on the left, in the diagram above, you can determine if the cranks will clear the chainstays by measuring the chainstay width at the corresponding points. You want to make sure that you have 3-4mm of clearance on both sides to account for any frame flex that may occur.
If these two points look positive then eeWings will fit your bike.