Rick Lance wrote:On the left side of the motor there are two such rubber coated metal caps. The one for the balancer shaft goes rubber side out since it is exposed and cosmetically looks better finished that way. The crank cap is to be mounted rubber side in for the reason you mentioned, Wolfgang. That is the stock configuration. Your illustration shows it mounted correctly. Of course, this cap is concealed behind the plastic cover that captures the oil lines so appearance isn't an issue.
Rick,
You mention that Wolfgang's positioning of the blind seal is 'stock configuration'. However, the following three micro-fiche illustrations, the RD500 Service Videos posted by Yamaha Motor Co. LTD., the early release photographs of the 500 dismantled for press photos prior to and just after release. All show the seal being installed rubber side out.
Per the conclusion of assumption that the oil is forced is a misconception. The oil is washed out of suspension in the fuel/air transfer and temporarily adhered to the primary internals until washed further by each pulse of the intake cycle, thus making it's way through out the engine. Since the bearings are not in the middle of these pulses, oil is not forced into them via the intake pulse. Rather, the distribution of wash effect is carrying the oil throughout the bottom end as a wash. There is even some consideration that there may also be a low pressure effect that each bearing produces at RPM actually pulling oil into itself.
RZV500
RD500LC (47X)
RD500LC (IGE)
RD500 Service Video #6 see 2:47 for the seal in the rubber side out position.
http://www.youtube.com/watch?feature=en ... GpvVtONB9U" onclick="window.open(this.href);return false;
Early Press Release Photgraph
http://www.rd350lc.net/RD500LCengineV.JPG" onclick="window.open(this.href);return false;
As a rule I always install the blind seal rubber side out and on the other seal Wolfgang gave the example of those always go with the notches in or numbers side out.
Regards,
Bill Wilson
Wilson Performance
Lee's Summit, MO
http://www.wilsonperformance.net" onclick="window.open(this.href);return false;
Member RZ500 Owners Group #573
816-377-3185
WVWRZ500N@aol.com