Destricting my Piaggio Fly 4T4V

[Tim N]

Hi everyone,

This will be my first post on this forum. Since dutch scooterforums are outdated and non-active, I am happy to enter a more international forum

So I bought a Piaggio fly 4T4V about a week ago. This is my first 4T scooter while I was used to the aggresive performance of 2 strokes. So I knew things wouldnt be the same when talking about performance and torque, but I wasnt expecting the slowness of the scooter.

So the things I did:

Derestricted the vario (pulling out the vario-ring) 
Derestricted the CDI unit
Changed the vario to a Malossi Multivar (the one I had on my 2stroke piaggio scooter)
Left it with the same rollerweights: 5,2 grams
Changed the jet from 75 to 78mm

And now I'm left with a super slow upbuild to full speed. Even at full speed I cant get over 62km/h.

Something must be up before I have to change to a 80cc cyllinder. Any thoughts?

Today I was changing the weights when I discovered a difference at the crankshaft. In picture 1 you can see my 2t scooter with a 'naked' crankshaft. In picture 2 you are seeing my 4t scooter crankshaft. The difference is the plate that is positioned at the back of the variateur. I never heard of any other vario restrictions other than: a plate that is mounted on your vario, a varioring and the slidebox. Do you guys know If this plate is a restrictor?

Thanks!


Picture 1:

Picture 2:

[jeff84]

no that plate is your oil pump cover. its not a restriction.

are you getting full travel out of your drive belt? meaning is it reaching the outer edge of variator?

[Tim N]

Thanks for your reply Jeff,

In that case, I will not touch that cover

I guess it is reaching the outer edge..I dont have any other restrictions left.
I should be getting more out of it than 62 km/h right?

[jeff84]

I have an older 2 valve piaggio fly and it could do nearly 80 km/h. it did take a long time for it to reach that speed though. that was using a polini variator with 5.5gram dr pully sliders, and a blue polini contra spring. after I got the big bore kit it would reach that speed easily and surpass it slightly.

do you have a tachometer? how many rpms are you turning at your top speed?

[Tim N]

Sounds good! Now I'm wondering if a 2v and 4v is that much of a difference.. Your setup beofre the big bore kit sounds similar to mine. I still have a white Malossi contra spring available but I dont think that would make the difference. Did you derestrict your CDI or did you buy one that is more fast? Also What is your jet size?

Unfortunaly no tachometer but the RPM sounds high and constant already at 30km/h.
Thanks.

[jeff84]

I bought the scooter used and the cdi was bad so I replaced it. I just bought an unrestricted stock cdi.

[Tim N]

Anyone else having ideas on what else there is left to do to increase performance ?

[jeff84]

well I was just shopping for a new belt, and its quite confusing. several vendors have the wrong belt listed as being for this scooter. this is the correct part number 842907. it is 756mm x 18mm. when I bought mine it had the wrong belt installed. check yours to make sure it is correct. mine would only go 30mph with the belt it had installed which was far too short.