When the price of gas jumped up, I took my TS185 out of storage and fired it up - no problems - what a dream!
This baby's got ~20k+ miles (broken speedo years ago) and is leaking tranny oil out of the transmission shaft that holds the chain drive to rear wheel.
My question: Is it possible to replace the oil seal without splitting the engine in half? Any tips? If the engine needs to be split, my book calls for a special seperating tool - can I split the engine in half without this tool?
Thanks for this forum!

Not familiar with TS185, but every bike I am familiar with the transmission output shaft seal can be removed without splitting the cases. Remove the sprocket, clean the area around the seal to make sure there is no spring clip or other seal holder. Remove any seal holder (there probably won't be one, the sprocket usually does that job.) There may be a sleeve over the output shaft, remove the sleeve. Remove the seal using a hooked tool.

Thanks for giving me the confidence to try to remove this seal 'on the bike'.

What constitutes a 'hooked tool'?
Would I file half the head off a large nail?

How would I use this tool to break the seal loose?
I'm not optimistic that a good tug will pull the seal off. Do I need to rig a slide hammer: like vice-grip clamped to point of nail? Or is there a particular prying technique?

I'd like to 'go in' with as much info as possible.
Thanks for your help.

The seal there usually leaks because the shifter has taken a hit and damaged the seal. This sometimes even leaves the shaft bent, so that's worth checking too.
The seal can be pulled out without any need to split the cases. The easiest way is to do what everiman said, take off the covers, clean all around the shaft and seal. Lean the bike over on something large and soft (passing children work well...!) so that the oil is on the other side of the gearbox.
Find some self-tapping screws (or some wood screws, it doesn't really matter) that are not bigger that the width of the seal.
Using a drill, about half the size of the screws you have, drill three holes at even spaces around the seal, closer to the outside edge than the centre. Screw in three screws, and use a set of locking pliers to ease the old seal out.

Don't throw away the old seal. Use it as a drift to protect and ease the new seal in. A short section of pipe, that is the right size to put pressure on the outside rim of the seal is the right way to push the seal back in. If you use a flat ended punch or something like that be very careful to take it slow and tap around and around the seal. Before you do, make sure there are no rough edges on the end of the gear shaft and put oil on seal and shaft to make sure it slips on without damage to the seal lips.

If the shaft is bent I have been known to ummmm persuade it back straight by putting a pipe sleeve over and using a big hammer to bend it back. CAUTION!!!!! Do this at your own risk!!! I have got away with it several times, but there is a big risk of major damage to the cases and shifting mechanism.

Regards

Nigel in NZ

__________________
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I finished the job!
This was FAR easier than I feared.
The nail with the filed head & 2 vice grips used as slide hammer popped the seal right off on second application on opposite side.

Thanks for the tip Nigel, I noticed that a drop of oil came out of the shifter shaft seal when I was hammering on the shift lever. I'll keep an eye on this to see if it's also leaking.

I'm off to chasing down a leak of 2-cycle oil.

Thank you very much!