SYM HELPS
- Thread starter c74n712w
- Start date
Rowe
Well-Known Member
well you can derestrict you standard exhaust but its pointless to be honest, just buy a sports one 
the variator is also restricted, you can just buy a malossi or polini one allready derestricted or derestrict your standard one
but if you dont know what your doing its suggestable that you take it into a garage somewhere as you will void your warrenty otherwise
the variator is also restricted, you can just buy a malossi or polini one allready derestricted or derestrict your standard one
but if you dont know what your doing its suggestable that you take it into a garage somewhere as you will void your warrenty otherwise
Areomyst
Scootin' America!
If you get an upgraded exhaust you should also re-jet your carburetor on the DD. I've derestricted a few SYM scooters and if you remove all the restrictions on the exhaust it will run lean. Moped Hospital has performance exhausts for these, just order it for a Kymco ZX50 and it'll fit just fine. www.mopedhospital.com
Cheers!
~Josh
www.mopedhospital.comCheers!
~Josh
I know of three restrictions:
1) Remove the washer behind the variator pulley, limits the belt from riding all the way up the pulley. ~ +2 mph
2) Remove the washer donut in the intake manifold. Pull off the carb and you will see it. It is a bottle neck; restricts the full potential of fuel air mixture path.
3) The exhaust pipe has a second pipe coming from the j bend near the exhaust flange on the engine. Either cut off the extra pipe and weld it close or buy an aftermarket pipe. I would of bought an aftermarket pipe since most people will replace the bore for a bigger one.
With all of the above restrictions remove, you can jet up the stock carb. Buy a 85 main jet and replace the stock main jet.
I think the stock CDI is also a restriction, you can replace it with an aftermarket CDI.
1) Remove the washer behind the variator pulley, limits the belt from riding all the way up the pulley. ~ +2 mph
2) Remove the washer donut in the intake manifold. Pull off the carb and you will see it. It is a bottle neck; restricts the full potential of fuel air mixture path.
3) The exhaust pipe has a second pipe coming from the j bend near the exhaust flange on the engine. Either cut off the extra pipe and weld it close or buy an aftermarket pipe. I would of bought an aftermarket pipe since most people will replace the bore for a bigger one.
With all of the above restrictions remove, you can jet up the stock carb. Buy a 85 main jet and replace the stock main jet.
I think the stock CDI is also a restriction, you can replace it with an aftermarket CDI.
BTW, I went from 33 MPH to 42 MPH.
Here is a similar link to deresticting the exhaust pipe:
http://flexistentialist.org/blog/ar...n-aprilia-scooter-or-most-any-modern-scooter/
Informative Link:
http://scootdawg.proboards59.com/index.cgi?board=discussion&action=display&thread=9167
Here is a similar link to deresticting the exhaust pipe:
http://flexistentialist.org/blog/ar...n-aprilia-scooter-or-most-any-modern-scooter/
Informative Link:
http://scootdawg.proboards59.com/index.cgi?board=discussion&action=display&thread=9167
Last edited:
Rowe
Well-Known Member
i agree with you there, dont derestrict your standard pipe, by an aftermarket one
one thing is though, i didnt know that the syms were restricted by the cdi, mine isnt as it revs to 10,000 on a standard cylinder
^Maybe I am mistaken. I thought I have read this somewhere.
Some local enthusiast recommends for little money while obtaining a higher top speed, derestrict the scooter (listed above) then buy a aftermarket pulley and gearing=> ~ 50 MPH.
Although my preference is to get a bigger bore, pipe, weights and springs, rejet then a bigger carb. Or save money then get everything at once since there will be less work and tuning. Start at the foundation then work myself up. It might be more money but I will end doing it anyway.
I also read that '
There's an old saying. "Fast, cheap, and reliable. You can only pick two."'
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