750 SF2 crankcase splitting tips

[TeddyG]

Greetings all,

From my previous posting about piston wear, the consensus from here is that I need to split the crankcase to examine and clean the slingers, and I could use some tips from you experts. I've examined the Green Book instructions, but wondering what else to be aware of, especially how to safely split the case by using a rubber mallet, since I'm assuming the liquid gasket will be stubborn and require some "coaxing".The Green Book lists the various components that need removal, and goes thru the general splitting process, but is anything else the Green Book is omitting?

I've looked for online videos, but only see one by Alder Marsh re-assembling a crankcase in time lapse.

Redax kindly posted these pics of the slingers that are pressed onto the crank "web"- is this "web"between the crankshaft center and flywheel? The slingers appear to be disc shaped with shallow shoulders, and muck gets trapped inside the cavities. Does the crankshaft center and flywheels need to be pressed apart to access the slingers? And what are the 5 metal rings in this attachment?

Before attempting to split the crankcase, I'd like to gather enough info to do this correctly.

Again, the bike came to me w 15K miles, it now has 18K miles, and I changed the oil 3 times and installed a billet sump cover w/ magnetic drain bolt.

Thank you very much

 

[redax5]

forget the 5 x metal rings, they are just something we machine that makes pressing the cranks back together easier

 

[Paul Marx]

This Teddy is my crankcase splitting tool.
Paul

 

[Exmoor beast]

If you get really stuck cases I would use an internal cramp with soft jaws to apply even pressure to both sides, spray up all the stud holes with WD40 and leave it. Mine had been together since ‘69 and they came apart without any difficulty. The reason people belt crankcases apart is because they’ve left one nut or bolt in! Never had to lever or jemmy open any engine I’ve ever done- I once bought a Triumph Saint police bike engine that had been stolen and thrown in the grand union canal, still came apart.Softly, Softly catchey monkey…
I’ve got a spare set of cases for a 750….

 

[TeddyG]

Thanks Redax and Exmoor,

Any other tips or advice on the whole process of dismantling the crankcase and the contents, and does the crank have to be pressed apart to access the slingers?

 

[piranha-bro2]

Thanks Redax and Exmoor,

Any other tips or advice on the whole process of dismantling the crankcase and the contents, and does the crank have to be pressed apart to access the slingers?

No. It will become immediately obvious how it all fits together once you have the crank out. It's actually pretty basic.

 

[1200ts]

Thanks Redax and Exmoor,

Any other tips or advice on the whole process of dismantling the crankcase and the contents, and does the crank have to be pressed apart to access the slingers?

The crank does not need to be pressed apart to clean the oil slingers but it makes it much easier to do the job when apart. And it gives you the opportunity to check the big end bearings. Wolfgang told me a year ago he will still rebuild twin cranks but not triples.

 

[TeddyG]

Thank you 1200ts