PX125E-new scooterists' first upgrade

Hello All,

I have a stock 1989 PX125E that i just bought this spring and have been reading quite a bit about upgrades.

This summer I would like to upgrade the exhaust system only.

I am not sure if i will do a displacement upgrade later on, so no need to plan for that.

I am wondering, if i were to only upgrade the exhaust, which one should i use?

And what difference in performance can i expect with an exhaust upgrade?

Or, on the flip side, is it pointless to upgrade exhaust only?

Any help is much appreciated.



if is only the exhaust I think would be a good idea a SITO PLUS.
You will have about 10% more power wide spread.

With other exhaust maybe you can get more power at high rpm but in my opinion it doesn’t make sense since the standard engine is not made with this attitude and you risck to loose on the low rpm. Pratically a more tecnic ehaust it will improve where there is little margin of improvement.

The SITO PLUS is a very good all rounder and you could keep in the future if you get a little tuning sickness. At that point you can enjoy with a DR 177 then a 24/24 or bigger carb and if want a little more a POLINI head. Time it 18, stay cool for the first 1000km, the DR kit tend to size, and then you will happy. If is not enough means you need money…

To upgrade the exhaust is not pointless… it is just that you don’t get much more with just this if you don’t think to go further in tuning:


sorry cur, rubbish sito is nothin but a standard exhaust with a bit more noise, 10%, god i wasted my money on a scorpion then didnt eye! sorry mate no offence ment to yourself[;)] best budget pipe in my view is the simonini, get a nice chrome one, stay away from polini cheap and nasty and dont last very long, only my opinion my opinion but.


I perfectly agree that other exausts perform better. But I think we always have to consider the global project of tuning.

I don’t say Sito for no reason.
I still have all the main exausts and when I tried SIP, Polini, Taffspeed, RZ, Simonini with almost standard PX125 engine I still think Sito plus is what is more coherent with what dumpbear want to get. Of course not the most powerful, but do you want to have the most powerful Px engine?
I don’t think so if I consider the topic.
Why then having more noise, spending more money in a very performant exaust if with the same money you can buy a kit and a carb togheter? And a kit and a carb togheter will give you more then a very good exhaust.
So my personal advice, for this case is again SITO PLUS.

But if you move up in tuning…that’s another history.


I aggree with Stubbsy, I have a chrome Simonini and a 26mm si carb on a standard PX150 lump and it is fine, much better than the standard exhaust. It looks, sounds and makes performance better, and is reasonably priced (you wouldn`t cry if it fell off and got run over by a car, as i know someone who had just spent £200+ on a stainless SIP did, you know who you are)