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Discussion Starter #1
Anyone ever have to replace the oil seal on the clutch shaft? I found a huge amount of silicone gooped up around the clutch shaft on the top left of the engine case. This bike had a persistent oil leak on that side and that does seem to be the source of it.

I've looked at the engine schematic. Its hard to say if I can remove that shaft without disassembly of the case. If I can pull the rod out while turning the shaft... will that work?

anyone?......
 

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Those are some nasty looking splines. Was it making any noise?
Wish I could help, but my clutch seals have been leak free.
 

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We talked about using 60% moly paste on the drive shaft splines before, right?

Locktite version call its an anti-seize paste, but its the same thing - as long as its 60% moly.

I dont recall any recent conversations about leaking clutch shafts on 650s.
 

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I have the same problem. To fix it, unfortunately, is necessary to remove the engine case, and rear cylinder head.

Cheap part, expensive work.

Edit: in my case, the leak is not so big, so I decide to live with it.
 

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Discussion Starter #6 (Edited)
I have the same problem. To fix it, unfortunately, is necessary to remove the engine case, and rear cylinder head.

Cheap part, expensive work.

Edit: in my case, the leak is not so big, so I decide to live with it.
Gah!.... :( Thats not what I was hoping for. Well. Mine is a little more persistent. I will have to investigate further. I'm waiting to see if I can come up with the money to buy a dang table lift. I have the frame lift, but I don't trust the thing. I'll also be taking a look at the crank case vent tubes to ensure they are not plugged. If the crank case gases don't have an escape route, seals leak.... sometimes really bad. Mine is not bad idling and revving, but riding even a short distance, puts a pretty persistent film of oil down the side of the engine. Something that MUST be fixed.

The final drive was STRIPPED... there was no noise at all, LOL. My "new" ones are properly greased. I'm waiting till next week to order the new tire, tube and brake shoes for the "new" rear wheel. The old one is cracked bad around the wheel bearing. Easiest thing to do is replace it. When I'm done, the only original parts will be the final drive housing, shaft and the brake backing plate.

I did slap it together to pluck around in the yard and run through the gears a little....



While putting around the yard, I found that my size 10 foot does not fit between the heel/toe shifter on this bike. Luckily, I have a toe only shifter in my shop. I will be putting that on when I have time. :)
 

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I cut the heal shifter off my 650 about a week after I got it. Drove me nuts because I kept stepping on it when I moved my foot.

What lube did you get for the splines on the shaft drive. There use to be a few out there, honda had one for the gold wings and their other shaft drive bikes. I ended up getting the Loctite LB8012

this stuff:
https://www.zoro.com/loctite-anti-seize-moly-paste-8oz-brush-top-can-234227/i/G2312012/feature-product?gclid=Cj0KCQiA6ozhBRC8ARIsAIh_VC2Q3BXbqQqxppvh5VrM7yXz7NIA-ylUVQ9MXhXZnUenoLGjtdwsXuwaArhlEALw_wcB

expensive stuff, like $35 for maybe 8 ounces?
 

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not sure what you mean by clutch shaft, a couple years ago someone said the oil was coming thru the case where the wires from the stator are routed. he said he cleaned them real good and sealed with rtv sealant from the inside. the case has to be exceptionally clean to stick. you might not want to put sealant inside the engine so i would think about it before committing. anyhow do a site search on cases leaking i'm sure it's been talked about before.
 

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Discussion Starter #9
not sure what you mean by clutch shaft, a couple years ago someone said the oil was coming thru the case where the wires from the stator are routed. he said he cleaned them real good and sealed with rtv sealant from the inside. the case has to be exceptionally clean to stick. you might not want to put sealant inside the engine so i would think about it before committing. anyhow do a site search on cases leaking i'm sure it's been talked about before.


Item #24 is the clutch rod. The seal is #23.

Its the lever on the top left of the case that the clutch cable connects to to disengage the clutch.

As for grease, I have some Loctite on order. I greased mine so it wasn't dry while I verified everything else worked like its supposed to.... and found the oil leak. So far, that looks like the only issue I have left other than tires.
 

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I pictured the shaft differently but now that you posted the drawing it seems odd that shaft would leak.

Im not sure the engine oil level is higher than that seal. Check you oil level and make sure the engine is not overfilled.
 

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Discussion Starter #11
it isn't. I'm sure crank case pressure has a lot to do with it... which is why i'm thinking that I need to make sure the vent tubes are clear up to the intake.
 

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There was a rider here within the last year, who's bike was blowing oil out of the crankcase breather hose into the carb intake airbox. Long story short he did a dry and wet compression test and learned his rings were shot and he was getting a lot of blow-by from the combustion stroke into his crankcase. I think you said you did a compression test on your bike already (I might be thinking of someone else), but even if you had bad rings as long as the crankcase breather tube is not kinked or collapsed any case pressure should blow into the air box, not thru a shaft seal. There is no PCV valve or anything that should obstruct that breather hose path (unless someone pulled the hose off the air box and plugged it.

I have read about HD engines that had crud build up in the oil return path from the top of the heads back to the sump. When the engine runs the heads would fill up with oil by the cams, and then blow oil out the crankcase breather hose. But again that should not build any pressure in the case to blow out any seals.

Unfortunately for you what you are seeing is unusual for these bikes. It might just be bad luck and you got a bike built with a defective O-ring on the clutch shaft.
 
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