Re: speedo cable leak....
Not sure if the R100 GS uses the same hollow bolt as earlier 5-speed boxes, and I know paralever models have a different seal/vent arrangement at the output shaft. But if it is supposed to use the same hollow bolt to vent the box check to make sure the bolt that holds the speedo cable in the transmission has a small hole through it and that it is not plugged up.
If someone has replaced that bolt with a solid one or its plugged with dirt or sludge, the transmission would try to vent up through the cable boot as the gear oil warms and expands while riding.
Merritt Island, FL
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