I had read in this thread that some people suggested sanding down a sharp edge to prevent snagging the filter roll. And some one a video with leakage around the filterThe Di-7 has been upgraded to a larger motor and all of the feedback we are hearing has been overwhelmingly positive. In instances where a Di-4 user has experienced issues with their motor, we have been replacing those too and have heard good feedback as well. Most instances of modding we hear about aren't to the units themselves, but rather their filter sock holder or coming up with an alternate adapter plate (some folks are selling 3D-printed versions) so the Klir will fit in non-standard sized sock holders.
