Hi, I am part way through restoring my Primavera, I have a good friend working on the engine who is an excellent mechanic but doesn't normally work on scooters.
He had asked me to get some parts, but I know nothing about engines so I am struggling. He has been told that the main bearings and seals are a good idea to change, could anyone advise the best SIP parts? I am on a budget (aren't we all) so cost is an issue, but I am willing to buy better quality if there is enough benefit to it.
you probably have more information since you wrote the post, however the "golden rule", when restoring a vespa engine, is to exchange the following:
All bearings, oil seals, o-rings, gear selector, sealing kit, clutch disks+spring, rings for piston, points & condensator. Check also if the kickstarter gear is in good condition, if not it's worth exchanging it, does not cost a lot.
They are all available here on SIP, search for "bearing kit vespa primavera" and same for all other items and you'll find what you need.
If the main parts (cylinder, piston, crankshaft, gear box) are good to go, the above is all you need to have it back running reliably for long (caruretto and filter to be cleaned as well :-)!