My second ZX50

[Quintin79]

after seeing the power increase in my 80cc upgrade on the original scoot, i couldnt help myself and found this in the classifieds for $400.  bargain - its original, runs good, all the faring is tight and all the tabs are still in tact.  it just looks bad because there are scratches and cracks and its faded.  most people wouldnt touch it but i can see potential!

i think ill turn this one into my run-around scoot.  it doesnt have to be hardcore but it still needs to have the power to pull 170kg (my wife and i) up decent hills. 

i have a leo vince exhaust, but is there anything else i can do to the stock engine, like a carby upgrade, in the mean time?

can anyone summarise what roller weights and clutch springs do?  or link to an explanation? 

[MotoRandy123]

I don't have anything specific to your scoot but the rollers set the fixed RPM.
That is if you whack the throttle open the rev's will rise to a point and stay there
until redline. That RPM is set by the rollers. So on a 2 stroke the rollers should
match the peak RPM of your pipe.

The small clutch spings set when the clutch engages. If you engage before power
 is there it will accelerate extremely slowly until the rev's rise. I had an Aprilia like
 that, it would take 4 - 5 seconds to take off!

The contra spring balances the rollers. It is the power that holds the gear lower
under torque. A stronger one will seem like lower weight rollers (so higher rev's) and
so it will have more power to climb hills (so will do that faster)...

It's a complex yet simple setup so while someone could tell you their setup it might
work different on your (same model) bike...

[naughty lee]

Skim the boss to 34 mm and fit 5 gramme rollers. It'll go like hell

[Quintin79]

when i first took it out i was getting 42kph with the limited CDI.  pretty weak.

i swapped the CDI for an unrestricted one and threw on my leo vince and the speed went up to 49kph.  still horrible!

took the variator off and found that it had the restricted boss so i have one on order from SA.

[theaggravatedjew]

So is the one from scooter assasins already the shaved down size?  Im running he boss that came with the jasil variator but I didnt measure it. 

[Quintin79]

this one pictured above is approximately 37mm.  SA's version has no shoulder and is 36mm

[naughty lee]

Use the standard boss, just skim it down to 34 mil on a bench grinder. Use the side of the stone to get it as flat and even as possible. An old cup with some iced water also comes in handy!
The mimimum it should do will be around 53MPH ( around 85KPH )

[Quintin79]

took out the restricted boss and replaced with an unrestricted one and now i get 59kph.  better but still crap.

i looked into the leo vince exhaust and saw that it had a restricter in it.  ill remove that and repost results.

[Raindrop]

dude listen to people ! file the damn boss drive down 34 mm i think .. these guys no there sh** !

[naughty lee]

dude listen to people ! file the damn boss drive down 34 mm i think .. these guys no there sh** !

The length of the boss determines the maximum gear ratio on the variator..mmmm perhaps I should upload a video ?

[Raindrop]

ya but i change all mine to 34mm works graeat