Crank Geometries
Figure 1: Image showing connecting rod length | Figure 2: Image showing stroke (Stroke is also difference of piston height at TDC minus BDC) |
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Below is a collective table of many of the common crank geometries, their rod length (either 89mm long rod or 85mm short rod), and their strokes (38mm, 40mm).
Crank Rod Stamp | Rod Length | Stroke (+-0.5mm) |
ZL40MM | 89mm Long | 40mm or 38mm |
AF80 | 89mm Long | 40mm or 38mm |
Zeda-80 | 89mm Long | 40mm or 38mm |
No Mark | 85mm Short | 40mm or 38mm |
Z-L | 85mm Short | 40mm |
ZAE-50 | 85mm Short | 38mm |
ZMN80 | 89mm Long | 40mm or 38mm |
ZMN100 | 89mm Long |
This list may not be 100% up to date or accurate. China often changes and mixes up crank parts causing random variations of these. Please measure yourself to be sure.