Ruckus variator VS. Dio style variator

[hopkinsproshop]

Hello-

I need some opinions..... Hopefully some that have tried what I am thinking of doing.

I have a AF16 model engine and I am doing a few up grades. I am going to purchase a Polini variator for the engine and have heard swapping in the Ruckus style variator will give a little more top end. I realize I have to work the case a little to fit.

Question....

Will the Polini Ruckus variator give me more ( a noticable difference) on the top end than the Polini Dio style variator?? They are basically the same price, so if the Ruckus style is a better choice I will go with it.

Question#2

If I go with Ruckus variator, (it is larger in diameter) will I have to use a different size belt, longer possibly - wider to allow the belt to ride all the way to the outside edge of the pulley???


Thanks in advance for any help..

[Wheelman-111]

Greetings:

The Ruck-style Polini is 94mm where the Dio-style is 91. This theoretically gives more "overdrive" effect, even with a stock belt. The 641mm stock belt shouldn't bottom out in the larger rear pulley.
However, I'm not for certain that the stock OUTER front pulley face doesn't limit belt travel toward the edge.

In any case upgearing won't give more top speed unless engine power increases enough to take advantage of the taller gearing.

A ZX (larger) rear pulley for sure requires a longer (654 or 669mm) and wider (18mm) belt, as well as more case carving and a longer (2.5mm) front pulley boss.
The benefit is stronger take-off with taller transmission gears.

[Petrock's 1984 Spree]

Are there any places that sell those rear pulleys cause I can't seem to find them anywhere.
Or even something close to a zx rear pulley that would have the same effect?

[eliteguy50]

... In any case upgearing won't give more top speed unless engine power increases enough to take advantage of the taller gearing. ...

I agree with Wheelman, your sa50p will not have enough power to notice the difference between the Polini for Dio and the Polini for Ruck.

[eliteguy50]

Are there any places that sell those rear pulleys cause I can't seem to find them anywhere.
Or even something close to a zx rear pulley that would have the same effect?

I bought mine as a kit from VT Cycles in HI. You can get the ZX pulley from a ZX or new from the dealer. Be sure to inspect the welds before use, they may need additional welding before servicing a BBK engine.

[Petrock's 1984 Spree]

Alright I'll definately be calling VT about that! Thanks!
Oh, yeah the welding thing isn't a problem, i always make custom stuff a littler beefier than it probably needs to be so I'll just weld the thing all the way around instea of screwing with some spot welds
Ya just gotta be careful of the heat distortion, that always is such a pita

[eliteguy50]

Alright I'll definately be calling VT about that! Thanks!
Oh, yeah the welding thing isn't a problem, i always make custom stuff a littler beefier than it probably needs to be so I'll just weld the thing all the way around instea of screwing with some spot welds
Ya just gotta be careful of the heat distortion, that always is such a pita

My VT pulley was good. I have heard bad things about the actual Kymco part though. The other thing when making things "beefier" is to remember that this is a balanced rotating assembly.

[Petrock's 1984 Spree]

Alright I'll definately be calling VT about that! Thanks!
Oh, yeah the welding thing isn't a problem, i always make custom stuff a littler beefier than it probably needs to be so I'll just weld the thing all the way around instea of screwing with some spot welds
Ya just gotta be careful of the heat distortion, that always is such a pita

My VT pulley was good. I have heard bad things about the actual Kymco part though. The other thing when making things "beefier" is to remember that this is a balanced rotating assembly.

Maybe I'll tig weld it then. That'd be really bad if I threw the thing off kilter

[eliteguy50]

Alright I'll definately be calling VT about that! Thanks!
Oh, yeah the welding thing isn't a problem, i always make custom stuff a littler beefier than it probably needs to be so I'll just weld the thing all the way around instea of screwing with some spot welds
Ya just gotta be careful of the heat distortion, that always is such a pita

My VT pulley was good. I have heard bad things about the actual Kymco part though. The other thing when making things "beefier" is to remember that this is a balanced rotating assembly.

Maybe I'll tig weld it then. That'd be really bad if I threw the thing off kilter

Keep a nice steady bead and you will be fine. That is why I like the spot welds for that, easier to keep them equal and fix if I'm heavy one way or the other.

[Petrock's 1984 Spree]

Yeah true. I guess what I could do is do 2 spot welds across from each other, then another 2, and another 2. And go til I have 16. That should cover the entire thing

[hopkinsproshop]

Ok gotcha. If I were to add a pipe and rejet the carb accordingly do you think that would add enough extra power to pull the larger variator?

Another question... I had thought about changing out the rear gear set to a 9:1 ratio for more top end. Assuming I changed the variator, upgraded the exhaust and rejetted the carb would the change of ratio to 9:1 and the variator be too much for the stock 50cc engine??

I guess what I am trying to do is squeeze everything I can out of this 50cc. I plan to increase the bore size but I would like to use as is for the time being. But I would like some more speed.

I had also thought maybe if I did change the variator and the gear set, maybe to tighten up the grab springs in the clutch and put a stronger center spring in to give me a little more "off the line" increasing rpms, and also extending the shifts to compensate for the gearing???

Thoughts????

[Wheelman-111]

Greetings:

Leaving the engine completely stock, Flash III went 49 MPH with only a re-tuned variator, 9:1 gears and a 90/90 rear tire. At the time, the engine - and stock exhaust pipe - had less than 50 miles on them.

If your engine's output is healthy, then yes the 50ccs have enough power to pull 9:1s. If it's got a carbon-clogged pipe or the ring seal has worn to iffy, taller gears won't make it faster.

Also remember you're going to need to swap gears again if/when you add the big-bore kit. The 9:1s are a good match for stock power, but not tall enough to keep a BBK's engine RPMs in the safe zone.

[hopkinsproshop]

Well I am hoping mine will do the same.

It has 118-120 lbs of compression. Hopefully that is decent.

I have purchased a 28mm V8 pipe, I am afraid that could kill alot of my bottom end, but I am going to try it. If it does I will take it off and wait till the future when the BBK goes on.

I am definitly going to go with the 9:1 gear set.

All of this being said, would you go with the Ruckus variator or the Dio style??

[Wheelman-111]

Greetings:

The V8 might require a little finagling to get the gasket to sit right. The Honda exhaust port is designed to fit the Honda pipe and seal is accomplished with a "Donut" style stock gasket. I've never mounted an aftermarket pipe to a stock head, but maybe someone here has done it. Whatever you do, don't allow this critical juncture to leak. You can see pretty quickly if there's oil seepage. I sold a V8-28 to someone who reported it was fine in the low-end on his 50cc bore, and it helped on top quite a bit.

The honest truth about variators is that I'd recommend the Dio style for your build. A bigger drive face theoretically allows more over-drive, but since you're installing taller gears that's not critical - you may not even need all of the smaller cone's potential running stock-ish power. Also, the stock outer pulley face may not allow the belt to ride all the way to the rim of a 94mm inner face, so all the messy case-carving may not pay off.

[hopkinsproshop]

THANKS Wheelman!!

Good info, I think I am going to just go with the standard size variator then and get the other gears swapped in and go from there. I am going to fit the pipe up and try and make a gasket. Hopefully I can get it to seat properly and seal up.

Awesome feedback, thanks again.