Is my ST1100 the only one that leaks a little oil?

Ned in Utah

Ned in Utah

Joined
Apr 8, 2017
Messages
178
Location
Utah
Bike
1994 ST1100
Seems like I've been chasing oil leaks ever since I bought my ST ten years ago. First it was the 28 amp alternator and then the sight glass o-ring, both which I fixed. Now there's something else that I can't track down. Was advised it might the rectangular gasket at the rear of the motor that I was told often leaks, but I replaced that and it didn't fix it. Leaks like a drop or so a week that seems to collect on the bottom of the oil pan then drips on the garage floor. I know, I know it isn't much, but still....

I love the bike. Starts right up, runs like a top and is a joy to ride. Has taken be from Prince George BC to Tuscon, AZ to Sturgis to the Pacific Ocean and everywhere in between. I don't know anyone else who has one, so don't know...do they all do that a little? I'm about ready to throw in the towel. I know the old Brit bikes leaked like sieves and a lot of Harleys leak some, but I've never had a Japanese bike that did. I know it's 30 years old, so is this just "part of the experience"? Is mine the only one that leaks?
 

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Roger said:
Gear lever shaft seal? It was on mine.....
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Roger, I really appreciate the reply. I'll go pull the bottom plastic and take a look. Can that be replaced from the exterior? Is that something you were able to replace yourself? Looks like maybe just a matter of removing the linkage from the shaft and working the old seal out with a dental pick?
 
@Ned in Utah , when you're doing your oil change, do you replace the crush washer (drain bolt washer) or you are just re-using the same one ?
Mine did that too, last year. It seemed like my drain bolt was tight, but not tight enough. Now, I use a torque wrench (don't want to overtight).
I also had the under oil pan covered with a very thin layer of oil and dust at the end of the season last year. I suspect my drain bolt was not just tight enough, since I was so scare to overtight it.
 
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Well, I pulled the belly pan, crawled under it and checked. Oil definitely leaking from the gear shift shaft seal as Roger advised. So I ordered a seal. It's not easy to find the part number. In case anyone is curious the seal is hidden on the REAR CASE parts fiche #11 part number 91203-KK3-830, 14X22X5. And taking ChriSTian_64's advise, a couple of new drain crush washers. I hope that's the last leak.
 

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I don't know if this is useful, but on my '78 CB550 that is also leaking at the shift seal and also is going to be changed this winter, the advice is to protect the seal from the splines on the shift rod with tape or thin plastic as you slip it on. If you don't, you may create potential seal damage that can lead to premature leaks.
 
Follow up on the oil leak drama. A week after replacing the oil drain washer and the shift shaft seal, everything is still dry under the the 94 ST.

The seal was not that tough to get out, just a small flat head screw driver and a Harbor Freight dental pick. The shaft splines are actually smaller diameter than the shaft seat, so getting the new seal over the splines safely is not an issue. I was able to get underneath it to get the seal while it was on the center stand without having to lean it on it's side. Just had to remove the belly pan.

Thanks to Roger and ChriSTian_64 for their advice. I hope this is the last leak. I've replaced about everything else. Still love riding the stinking thing. Didn't really want to lay out $8000 for the FJR I was looking at anyway! At least not this year!

Thanks again for all the replies.
 

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Andrew Shadow said:
Seal bullets. They protect the seal while sliding it over a harmful surface.
They should be used whenever sliding a seal over any potentially harmful surface.
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Cute.
I notice these cartridges appear to have a roll crimp, and no rim at the base to trap a seal or o-ring.
 
Sadlsor said:
Cute.
I notice these cartridges appear to have a roll crimp, and no rim at the base to trap a seal or o-ring.
Click to expand...
If they have not been abused they are as smooth as a baby's butt. A touch of O-ring lubricant results in an easy seal install with no damage and no rolled over O-ring, which is to be avoided.
 
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