Exhaust change made my NRG slower

Mantas

New Member
I had a stock exhaust on my 2012 Piaggio nrg and i bought a Yasuni z kevlar and after the swap the scooter lost all speed it doesn't pull like it used to and the top speed is gone too. Before the swap it was doing 90 km/h max and it was accelerating quite fast for a full on stock 49 cc scooter. And now its just slugish
 
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arkAC

Active Member
Is restriction taken out of the exhaust?

Do you have some more info about your setup please:
-clutch springs weight/colour
-Roller weight
-Carburetor (main jet size) etc etc...
 
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Mantas

New Member
Everything is full on stock but the scooter's restrictors are taken out. Exhaust was put on yesterday so it was not touched from within inside. My next question is are the restrictors in the Yasuni exhaust ?
 

Mantas

New Member
To be honest my friend had the same Piaggio scooter with restrictors in it everywhere where they should be from factory and it felt like i never gave its best and i did have the same impression here. Do you know if they are hard to remove?
 

arkAC

Active Member
To remove that restrictor you can use a Dremel tool. It's not particularly hard to do but you'd better be aware that the restrictor not glides into the exhaust when using other tools than grinding tools.

For better speed and performance, additional you have to adjust the main jet size to a size bigger. Then you maybe have to adjust roller weight a bit.
 

Mantas

New Member
But in reality its quite weird how a "sports" exhaust gives you worse performance then one from factory
 

arkAC

Active Member
Yes and no.

Be aware that you're type Yasuni Z is known to be not more than a 50cc replacement exhaust, explained as low rpm. Yasuni design and shape is likely for beter performance yes.

If you don't want to remove the restrictor yourself maybe there's is a moped, scooter shop/repair you know of whom take care of it?
 

Mantas

New Member
Sadly there isnt any near me i will try it myself and also will install the rest of the lighter rollers
 

Mantas

New Member
Also it does rev even higher then with the old exhaust yet it doesnt pull. Fun fact the old exhaust was from a Aprilia sr factory not the piaggio one
 

arkAC

Active Member
Sadly there isnt any near me i will try it myself and also will install the rest of the lighter rollers
Succes with that.

By the way if you adjust the correct way, you'll achieve slightly more speed/ performance. If you still want more you have to look at different types Yasuni that has higher rpm/range ;)
 
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arkAC

Active Member
Depends on the amount engine power. Let's say if you're motor is a standard 50cc you might be better of with a lower range/rpm exhaust. When put a high range 70cc exhaust on a standard 50cc engine it will much less work or even not at all. Therefore you'd have to compare some Yasuni models that fits you're purpose. If unrestricted that Yasuni Z will do the job on any 50cc scooter.

All you have to do is find the right adjustments for the exhaust fitting to available amount of engine power.
 

Mantas

New Member
Well for the time being i have put my old one back and with the new rollers its nice plus its nice to be fast for a scooter again. I will investigate this with putting this Yasuni on some other piaggio family scooter to see and most likely sell it.
 
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