TS 185 crank seals how to replace?
 

Hi,
I've just bought a 1998 TS185 but it started to blow smoke after changing the gear oil.

This was totally unexpected as the compression seems really good and was running great before changing the oil with just a tinge of bluey smoke that looked and smelt normal.
The drained oil was clean and looked about half of the required volume which is 700ml.
Now with the new oil (Castrol 2stroke Motorcycle Gear Oil MTX 75w-80) the bike runs like the choke is on with way too much smoke which smells different.

My questions -
1. Would the clutch side crank seal allowing transmission fluid into the crank be the only explanation?

2. If so, on this bike can the crank seal(s) be replaced without splitting the inner casing?

3. If the inner casing does need to be split are there special tools needed to replace the bearings as well?

4. I have tried to check for play in the bearings by moving the timing side magneto up and down, as far as I can tell there may be a very, very slight amount of play would this be ok or is no play at all essential?

5. I have been searching for days for a manual for this bike to help answer these and other questions but the best I can find only covers up to 1981, is the motor the same? Any help in finding a manual or info also appreciated as I've turned up a blank - ebay, clymer, haynes, google, pdf searching etc

I would like to be fairly sure about the seals before replacing them because for me this will be a first and difficult with minimal tools.

Any help no matter how small will be greatly appreciated.

Thanks