[JesseK]

@Tottanka -

Inspect the CIM pinion gears themselves. It doesn't matter who manufactured them. In the past, we have received about 1 in 10 pinions as just completely unusable. In one case the gear teeth were complete triangles rather than the usual tooth profile. In another case the gear teeth were all 'skewed' clockwise. We usually keep them to make sure students understand the importance of verifying purchases before use, so I'll try to remember to get some pictures sometime before the season hits.