Modern Vespa

I am changing belt, rollers and variator tomorrow and don't know what type of grease or what I should use to hold the rollers in place

Don't put any kind of lubrication or grease near the transmission rollers, belt etc..
Have a look at this wiki if you haven't already. There are also a lot of youtube videos, the proceedure is very similar for any scooter.



GT200 CVT belt and rollers replacement.

Cheers

None...
Be sure you have them installed in the correct direction.
put the Variator, and Slide Plate together like a sandwich and push it on to the shaft. Over time those rollers do have a small amount of wear, I can't imagine their being any grease in the chamber, that would be a mess.

There a bunch of video's on Youtube.
If you can't find for your bike, search for Vespa, basically the same.

I can't stress: "Hand Tight, then Torque" !
I never use any power tools for this Maintenance.
When you need some extra torque for the removal use a Breaker Bar.

Keith,
Marietta, GA

You can put a dab of PTFE grease on them. Malossi and Polini both have a grease specifically for this purpose. I think it keeps the variator from locking them in place and wearing them flat faster when the belt is all the way up.

This applies specifically to the Piaggio engine in the MP3. The variator and roller materials are designed to be self lubricating and dry. If you put any kind of grease near them it will collect dust and dirt and generally gum everything up even if it doesn't escape onto the belt. What Polini or Malossi might recommend for their own products is entirely a different matter.

It's true you should not use any paste type lubricant but you *can* use graphite to keep things sliding along the way they should.
As with anything in life, use in moderation.