With these minimally activating tune settings, CRP was used to ensure good ion transmission after SID. Figure depicts a series of SID bar charts for charge-reduced CRP (17+), in line with the charge state used for the data described later in the paper. With the least activating tune parameters for Ubq (Figure ), no ions were observed in the mass spectrum or mobiligrams (Figure ). Increasing the post-Trap bias from 20 to 35 V (panel B) resulted in evidence for trimer, tetramer, and pentamer, which suggests poor collection of complementary ions (monomer to accompany tetramer, dimer to accompany trimer). Additionally, the spectra and mobiligrams featured low ion intensities. Panels C -F were obtained by adjusting the indicated helium cell deltas and bias. Comparing these panels reveals that tuning the helium cell improperly can result in ion transmission bias, depending on the relationship between the helium cell entrance and exit deltas. Panel E appears to feature native-like SID for CRP, however, the high m/z region was missing from the mobiligram, which was concerning because complementary oligomers and charge states were not present when they reasonably should have been. These product ions appeared when the helium cell deltas were increased to the values in Panel F.