Originally Posted by
30Tooth
R4 diffs are the same teeth count as the RRR so it's just a matter of doing some custom size rings ordered from(and now google translate fails to translate but is someone who operates lathes and such hope you understand) so the R4 diff with bearings sit inside that ring and the RRR eccentric.R4 bearings have a small diameter and these rings make them fit into RRR eccentrics.
You will save more monay if you buy a ready R4 from matching parts to RRR...