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Discussion Starter #1
I have a 94 Fatboy that has developed a Transmisson oil leak. The oil seems to be coming from the Belt pulley Sprocket and leaking down the side of the primary chain case cover when the bike is on the kick stand. Is this half way normal or to be expected? Do you think a bearing went out as the leak developed suddenly? I was planning on riding to Sturgis (1500 miles) when I noticed this. If I watch the fluid level and replace as needed, do you think it would be ok to fix later? It drips about the size of a silver dollar overnight.
 

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Hard call to make from a distance. If the leak comes from behind the belt sprocket odds are the sprocket has loosened on the shaft and if this is the case the bike will not make it. If the drive gear bearing is failing one would expect at least some noise, but you never know.

If this could be ruled out with certainty like prying on the sprocket with a bar and watching for movement it still wouldn't be a good idea to take the bike on a long trip, but total failure would not be as much of a concern. The risk of an ever larger oil leak near the rear tire would still be there though.

The wording seems a bit unusual, as fluid running down the inner primary could also indicate a primary leak, possibly from the mainshaft seal in the inner primary. This is a much less involved repair.
 

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Discussion Starter #3
Thanks Hippo, The oil is definetly tranny oil; I use revtech red syn. in the tranny and HD primary case oil in the primary. The oil seems to be migrating down the inner(next to the belt sprocket), outside wall of the primary case, the drip forms on the primary case drain plug (the lowest point) before it drops to the floor. I can't figure out how the oil is getting across the belt sprocket from the tranny side to the primary case side wall. I will try the prying, carefully, that you suggested. Thanks again.
 

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There is also a small quad seal on the mainshaft behind the inner race for the bearing that goes in the inner primary. This can cause a gearbox oil leak that seems to come from the inner primary.

While you need special tools to change it, as far as taking a chance with riding the bike, it would be one of the less critical scenarios.
 
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