Modern Vespa

Oops!
This is a strap wrench. The one in the link has a fiber reinforced strap. A 100% rubber strap might stretch too much.

https://www.amazon.com/Boeray-Multi-Purpose-Capacity-Adjustable-Handle-Yellow/dp/B07JDXBWQD/ref=sr_1_3_sspa?s=automotive&ie=UTF8&qid=1549803273&sr=1-3-spons&keywords=strap+wrench&psc=1

The first tool Breaknwind showed https://www.amazon.com/AutoRocking-Flywheel-Variator-Spanner-Motorcycle/dp/B07FY9HJGT/ref=sr_1_1_sspa?s=automotive&ie=UTF8&qid=1549802360&sr=1-1-spons&keywords=variator+tool&psc=1
is a what I use to hold the clutch. Another tool that makes this easy is a case splitter: https://www.amazon.com/Tusk-17-8668-Crankcase-Splitter-Separator/dp/B0039L9PSU I have used a steering wheel puller but this is a better option. You will also need a flywheel puller to get the flywheel off. Scooterpartsco has one https://scooterpartsco.com/recambi-scooter/scooter/flywheel-puller-buzzetti-for-gilera-piaggio-50cc-2-4-stroke-a It looks like you are getting this apart.

Thanks all. I ordered this part:

https://scooterpartsco.com/lx-50/lx-50-tools-and-repair/variator-tool-for-vespa-piaggio-aprilia-50?zenid=4470efbf2d9f4eb4fb89dba3ffaa1d44

I think this will allow me to remove the variator and the flywheel magneto. I might need to buy one of the tools suggested above to the the clutch out. It got suggested that I put bearings in freezer and motor case in oven to replace bearings. I'm only thinking I have to replace the crankshaft bearings and not the wheel shaft. I don't think this motor was flooded. There is no water damage or rust anywhere else but in the cranck case. Using temperature to get new bearings in necessitates the complete disassembly of the whole motor. If the only thing I end up replacing is the crank shaft, is there another way to getting old bearings out and new ones in?.

you can usually use a socket and a hammer to tap the bearings out, if they are stubborn you can use a heat gun on the case around them to get it to expand. Putting them back in you should use the method I linked in my last post. You can also use a crank puller like this: https://www.ebay.it/itm/CUPOLINO-ORIGINALE-PIAGGIO-BEVERLY-RST-E-MIC-125-250-ART-621469-SOLO-SCHERMO-/152088169553?nav=SEARCH

After you split the motor. You can visit a local machine shop and have them use an arbor press. I have one at work.
This is only if you don't feel confident about DIY the bearings.
I bet you'll need the flywheel puller. When I need a special tool, I make one. Don't screw up the fly wheel by cheaping out. Get the tool !

Oops!! Wrong link

I didn't have a puller tool when I took my fly wheel off.

And though this video is a little rough round the edges and done on a bench.......I applied the same principle on my LX50 and with one tap just like him it was off, and I didn't have a pry-bar.

Here is the correct link: https://scooterpartsco.com/recambi-scooter/scooter/flywheel-puller-buzzetti-for-gilera-piaggio-50cc-2-4-stroke-a I've used other ways but this is the best tool for the job.

Loving this thread. Any updates?

I would not have rebuilt the engine right away. I would have cleaned, reassembled and see if it runs.
Only then would I have dismantled it and started rebuild.

Might spend money on mechanical parts only to find electrics are U/S.

^^^this...

Not me. There was WAY to much indication of moisture in the engine. Moisture kills the bearings. If you run the engine with scored bearings it will ruin the crank and the bearing races in the case. Then you pretty much have to throw it all away and find a new motor. I'm usually not one to promote doing unnecessary work, but in this case, not splitting the cases and finding out for sure if the bearings were ruined could end up being much more costly.

-Craig

Sorry for the long pause. I had work to attend to and was waiting for the right tools to continue. I have now taken most of the stuff out. There has been no water in this engine other than in the crank cavity. Weird. I am having way too much fun rebuilding this engine. Here are some pictures of where I am now. I will try to split it open tomorrow. I am hoping to be able to take the bearings out and new ones put in without having to use temperature to shrink and expand parts. I don't want to take the wheel shaft out. Any thoughts on this?.

Ok. Couldn't wait and went ahead. Split it very easily. Here is the real damage. Glad to have gone ahead with it. Need to take one of the bearings off the case. There seems to be a rubber seal on one side.

Seal in one side of the bearing is pretty common. What bearing in the case do you need to replace? Flywheel side or drive pulley side? Pics cause theyre fun!

As far as the rear drive, did you drain the oil in it and if so, what color was the oil? Any water in it? Any noises that concern you?

I did drain the oil. Looked clear. No water. No weird sounds. I'm replacing crank shaft, both bearings and piston. Took seals out. Need to clean everything and place new bearings in. Hoping that freezing them will allow them to slide in easily into the case. Any suggestions to clean the space where the bearings will go?.