Vision Starters have a design flaw that  allows them to fill with oil when the stock seal fails.
The solution to this problem is to install a replacement seal that has a spring on the inner lip.
There has also been mention of a sealed bearing avalable, but as yet I have no information on this.
Seal specs are avalable here.
Most bearing  supply houses should carry the seal.

Rebuilding the starter
Before removing your starter, drain the oil from the bike.  This is a good time to change the oil & filter if needed so remember to pick up a filter.
--Disconnect the negitive battery bolt & cable
--Unbolt the positive lead from the starter, unbolt the starter from the case.
--Remove the 2 long bolts holding the starter together.  Disassemble the starter, noting how everything fits together.  Make a sketch or take polaroid pics to help you remember where everything goes when you put it back together, if needed.
--Also note the position of the thrust washers on the ends of the armature.
--Note the alignment marks on the center casing and end plates for reassembly.
--Assuming you plan to replace the seal, grab the metal lip with a pair of pliers and pull it out, or, place a flat blade screwdriver under the lip and pry it out.
--Clean all oil soaked parts well.  I prefer to use spray type brake cleaner avalable at any auto parts store.
--To do this job properly you should find a reputable electric motor repair shop to turn the commutator, (the copper part the brushes ride on), Undercut the mica, (the white substance between the commutator strips) and balance the armature. they probably will be able to hook you up with replacement brushes and springs if needed.
--Remove the spring clip and working from the "sealed" side of the bearing, gently tap the bearing out of the casing with a long thin drift or punch and a hammer. be sure to tap on the OUTSIDE of the bearing.  This will take a little patence, so take your time.  If you use care, this bearing, if not worn out, can be reused.
--Install the new bearing by placing a socket SLIGHTLY smaller than the outer diameter of the bearing shell over the bearing and tap into place.
--Install the spring clip and the new seal in the same manner as the bearing.
--Before reassembling the starter, I would recomend drilling a small 1/16 hole on the underside of the starter casing on the seal end so that in the unlikely event that the new seal should ever fail, any oil getting into the starter will tend to drip out the hole.  This serves two purposes: 1) this will act as an indicator that there is a problem with the seal, and 2) hopefully allow the oil a path out of the starter before it reaches the brushes on the other end.
--Put the starter back together and install it on the bike, change the filter and add fresh oil.  Your hard work will be rewarded with a starter that hopefully will be trouble free for the life of the bike.

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Jason Morris offers a starter rebuild service for Vision owners
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