I have been looking for information about changing the crank seals on the above bike but not found anything so far.

I wonder if anyone could advise if these can be changed without splitting the cases or not.

Thanks, Daniel.

The only seal that needs to split the cases is the kickstarter one.

Yes they can be changed without splitting the cases. You will need a magneto flywheel puller for the magneto flywheel, and a good stout puller to pull the primary gear on the clutch side. There are seal housings that unbolt from the main engine cases making seal replacement very simple.

Sam

Brilliant, thank you for the info.

Really straightforward job... save for removing the primary gear from the crank shaft - brace yourself! There's many a helpful guide on how to, here on TC.