Modern Vespa

What is a multi variator in layman's terms?

What would putting on one do for my scooter?

Your scooter already has a variator. It's the CVT, Constant Variable Transmission. Or as Wikipedia would say:

A variator is a device that can change its parameters, or can change parameters of other devices. Often a variator is a mechanical power transmission device that can change its gear ratio continuously (rather than in steps).

See also: continuously variable transmission

The continuously variable transmission (CVT) is a transmission in which the ratio of the rotational speeds of two shafts, as the input shaft and output shaft of a vehicle or other machine, can be varied continuously within a given range, providing an infinite number of possible ratios.

The continuously variable transmission should not be confused with the power split transmission (PST), as used in the Toyota Prius and other hybrid vehicles that use two or more inputs with one output, despite some similarities in their function.

A CVT need not be automatic, nor include zero or reverse output. Such features may be adapted to CVTs in certain specific applications.

Other mechanical transmissions only allow a few different discrete gear ratios to be selected, but the continuously variable transmission essentially has an infinite number of ratios available within a finite range, so it enables the relationship between the speed of a vehicle engine and the driven speed of the wheels to be selected within a continuous range. This can provide better fuel economy than other transmissions by enabling the engine to run at its most efficient speeds within a narrow range.

CVT transmissions have been refined over the years and are much improved from their origins.

Okay, then: what would I get by upgrading a variator. I have heard people mention it and say it made a difference. What difference would an upgraded variator make?

Great post, Spock. But what's a "Multi variator"? I think I've heard that term also.

I was surprised at how many Nissan cars have CVTs.

We need to have separate discussion thread about the theory of an infinite number of solutions over a finite range. We could have some intriqueing arguments on that (and I mean arguments in the totally intellectual/scientific way!). I love the concept. But I think we'd have to make it a rule that you have at least 2 beers before posting on that thread since I see it as one of those sitting around the living room while drinking kinds of discussions... (Ok, yes, I am that dull!)

it makes a difference in your acceleration. i just had one put on my et4 with new clutch springs and i accelerate to my top end speed alot fast now. i had put on a sito plus about a year ago and didn't notice any change in my performance, but as soon as the new variator was put on i noticed a big change. it added a little on my top end speed too, i hit 69 mph.

Oh that easy.
A Multi Variator is Like a Woman

A woman that once your married she trys to change the person you are. By picking at you a little at a time to get you to conform to the person she really wants you to be.

I need more Coffee~

Did you get the Malossi variator? What weights did you put in? And which clutch spring?

I've been thinking about the same for my ET.

i put an athena variator in, there was a brand new one on ebay for $65 and i couldn't pass it up. it's not as good as the malossi one, but i saved about $150 bucks and my friend who put it in for me said he was happy with the athena variator he had. i'm not sure what weights or clutch springs he used though. i do know they were the malossi clutch springs though. i'll find out from him and post the info later.

I think you're specifically referring to the Malossi Multi-Var. I have no idea what makes it special vs a regular variator.

At least it's obvious with things like the Delta clutch - different spring rates, etc. Multi-var, no idea why it's called "multi".

Multi Var is just what Malossi calls it. The roller weights are about 1mm longer and come in lots of sizes. Of course, Malossi makes multiple sizes for the stock variator as well. The simple on that is this:
Lite weights = fast acceleration, reduced top speed
Heavy weights = slower acceleration, higher top speed

The weight of the rollers affects the rpm's, for example, lite weights = higher rpm's (which triggers the governor that limits your top rpm's, hence reduced top speed)

I copied Marc from this board. I mix lite and heavy weights into the variator. Another thing you need to keep in mind regarding the Malossi or Polini variator is that they're "racing" components, meant to wear out at some point. I'm on my second Malossi variator right now. I'm pretty happy with the Malossi, although I hear the Polini has 8 roller weights in there instead of 6!

Would greasy be kind enough to wade in on this? Bryce?

Would greasy be kind enough to wade in on this? Bryce? Technical moderators?

bump

I want no beers, but at the same time Lucky Bastard and lomunchi in a room. I would have the notepad and anytime two profound thoughts of totally opposite meaning cossed paths in the room i would make a little mark in my paper notebook. There would be no judgements and very few comments as the rest of us would be trying to remember what the little hashmarks in the notebook meant.
By the way has anyone figured out if a multiple variator is different from a normal variable variator, aside from the multiplicity of weights one inserts?

Google it.

So I did and got the same result you did ( and a few "pimped ride" photographs for added amazement-a 50cc converted to 172?) but no indication there is a difference between a multi variator and a regular variable variator.

Here we go again.
http://www.malossi.com/Catalogo/Cata_Main.asp?Marca=250&Modello=MO/VEE4ML1&Famiglia=0&CodArt=5111397

Malossi calls it a multivar, but it's a variator. Some people call shocks suspension, somebody might sell it called a dampener.

i'm going out for a ride, and to have some "adult beverages".
i shall return with enlightening information later...

best,
-greasy

Could have the best variator explanation ever later tonight. And by "best" I mean entertaining.

Man those things must wear out quick!

You must only be at 20,000 miles or so by now?.......

C'mon, what mileage do you have?

Those Polini's sound interesting, 8 weights, I didn't know that.

I only have a 'Little Old Lady on Sundays' 15,000mls on my ET, 11,000mls on the 'Multi Var', might be time to experiment with a Polini!

ow. my head hurts...

okay, spock hit most of the important parts, so i'll recap and then add some of my insight.

multi-var, variator; potato, potatoe. same thing. aftermarket companies just like to spice it up with the jargon.

in essence it's the same thing. it performs the same function, but is just built differently.

lots of aftermarket companies make variator kits: athena, malossi, polini, DR, and so on. yes, there are differences between each such as: build quality, performance, engineering, availibility of parts and of course, price. in general, an aftermarket variator is built a little better from an engineering standpoint; and offers more tuning options due to the selection of different weights and sizes of rollers.

okay so now you know what it is. here's how it works:
you have the key components: roller housing, backplate (or driveplate), gudgeon pin, and the oft talked about rollers themselves. note, that most kits utilize the stock 1/2 pulley-- this being the outer pully; and some kits contain extra tuning items: a clutch contra spring and sometimes clutch shoe springs. more on that later.

so the most basic explaination i can give is thus:
the rollers sit in the rollerhousing (variator) and are butted up against the drive plate. the drive plate is splined and indexes the crankshaft. the roller housing is driven by the drive plate as the crank turns. the rollerhousing rides on the gudgeon pin, the 1/2 pulley butts up against the pin and the drive belt sits between the two pulley halfs.

so, as the roller housing is driven centrifugal force moves the rollers outward from the center of the roller housing, thus pushing against the backplate. the back plate is fixed so as the rollers move out from the center they push the roller housing-- which slides on the gudgeon pin-- toward the fixed 1/2 pulley. as the roller housing moves, it comes closer to the 1/2 pulley and the position of the belt changes as it is pinched.

i know, that totally makes sense without the pictures, right?

so now to delve even deeper: the whole time the clutch is going, too. as the belt position changes uptown, it affects the clutch. driving the clutch faster or slower, depending on belt position. the way the clutch works is really simple. think old-skool drum brakes. it's all friction. so the clutch pack is three little brake shoes that pivot and they are retained by springs and this is attached to pulley that is driven by the belt. as the speed increases, the clutch shoes begin to succumb to centrifugal force and begin to consort with the clutch bell. as the shoes make the acquaintance of the bell, the friction material begins to heat up and take a bite thus spinning the bell and driving the gearbox-- oh yeah, i didn't mention that the bell is splined to the gearbox input shaft. so now you know. so as the clutch bites, the rear wheel starts to turn. now, the whole operation is controlled by a number of things: friction material, spring rates, interaction of components, the flux campacitor, and all that. but basically, the speed ot the clutch is really what matters because that is what is going to control the rate at which the interaction takes place. so, to make it even more complicated, the speed of the clutch is controlled by the how fast the pulley is moving. the pulley is two moving halfs, that are intergrated with a spring-- the fabled contra spring. the spring controls how the pulley reacts-- in other words, how much bite the belt can get and how or when the belt is positioned.

okay, so now that we've cleared all of that up, this is where the rubber meets the road. changing your clutch pack springs will allow them to get on the bell quicker or slower. changing your clutch contra spring will allow the belt to take a better bite, moving the position of the belt down or up, sooner or later and all of this controls where you are making power: radical wheelies, blistering midrange, or all top end huff.

and all of this is controlled by?
you guessed it-- the variator rollers!

lighter rollers giver you snappy accel. because everything is reacting quickly. the heavier rollers take more time to get there, but build more speed because the added weight pushes the variator further, moves teh belt higher, this moves the clutch faster and it bites more.

okay, now who wants to drink a few guinness and discuss valve timing and camshaft profiles?

addicted, edit as you see fit sir.

best,
-greasy

on a stock bike... not too much. i run a stock ET4 with a malossi variator and sito plus. i have better midrange and hill pulling than a stock bike.

but, it's all in how you tune it-- see other rambling thread...

if you never go over 55 and ride solo, get a variator and throw some light weights in there with the spring and have fun ripping wheelies and hustling to 55. if you're looking of highway work, go for the heavy weights and keep the stock clutch spring.

best,
-greasy

specifically, the ramps are a little more aggresive and the back plate contour is different. this keeps the rollers in the powerband a little longer. it also makes for a more on/off type of power delivery. the stock set up is geared toward smooth, even power delivery, where as a race part the malossi variator is all about power.

i think that the back plate is a little more beefy that the stocker and the fit between it and the roller housing is ALOT tighter. no slop there. personally that is one of the features i like the most.

best,
-greasy

yes, do keep in mind that any of the aftermarket components are considered for "racing and off road use only". take into consideration local and state laws before installing and/or use.

also take note that malossi roller wear out crazy fast. if you let them get too bad, you'll get down past the plastic and into the metal and eat the ramps up. then it's new variator time. this goes for aftermarket rollers in a stock variator and aftermarket variators as a whole.

i've installed two polini variators, both had six rollers. i've seen photos of an eight roller variator, but have yet to lay my hands on one. so far, i'm thinking it's all speculation. they probably mixed up a photo of a GTS one and an LX one...

best,
-greasy

Thanks, You manage to write an explanation in a style I can understand! I owe you an evening of "adult beverages"....

Greasy, I am reviving this thread because I still have a problem understanding the operation of a CVT. OK, I understand how the rotation of the crankshaft causes the rollers to move outwards by centrifugal force, and this squeezes the driving pulley making the belt assume a larger radius, fighting against the spring at the clutch end. So the pulley ratio changes, giving you a "higher gear" at higher revs.

But picture this scenario. You are travelling along a level road at 50mph. So the variator/clutch battle has settled at a particular pulley ratio. Now you come to a hill, so you open the throttle a bit to maintain your speed.
The hill gets steeper, and you end up full throttle but still maintaining 50mph.

Now the engine is putting out a lot more power, so there is a lot more strain on the belt. But this works both ways, forcing the rollers back at the CVT end, and opening the pulley at the clutch end. So is there any resulting change in pulley ratio? Ideally, you would want the rollers to lose the battle, so that you get more engine revs to cope with the hill, but I can't see why this should happen.

Can you explain?

Mike