SYM Owners Forum

Scooter Models => Mio 50 => Topic started by: badmotorscooter on June 26, 2020, 01:26:59 PM

Title: Derestriction questions
Post by: badmotorscooter on June 26, 2020, 01:26:59 PM
Just bought a 2010 SYM Mio 50 with 181 actual miles.  New OEM carb and battery.  Got a good deal, $1000. 

Originally I thought it was a 2014, but the seller disclosed it was actually a 2010 before purchase.
No big deal to me, except figuring out if the CDI is restricted  (the scooter still looks brand new).  I felt for sure the 2014 model probably had a limited cdi, but thinking the 2010 model probably has the plastic ring in the variator and "bean bag" in the airbox.

I have been researching the cdi restriction and found out SYM has a different wiring order on theirs.
Found several old threads about it but the pertinent pictures are no longer supported by photobucket.
Looks like the solution to using a generic cdi is simply switching the order of two wires in the pin harness, but with no pics I do not have a clue.

1. Anyone here know of a diagram or photo to explain the procedure?

2. Or maybe the 2010 model is just good to go with the physical limitations removed? 

Getting the scooter tomorrow and then I should be able to answer question 2 myself (hopefully).

Thanks in advance.
Title: Re: Derestriction questions
Post by: badmotorscooter on June 29, 2020, 12:05:03 AM

After a good washing and changing the engine and gear oil along with an airfilter service, removed the green ring from variator. Nothing in the airbox but the filter, but that has to be the most restricted stock airbox I've seen.

After I get it tuned in good running stock condition gonna definitely open the air box up and rejet the carb. No uni filter, I generally make sure the air intake system has about the same diameter as the carb intake. While a uni filter is good for high end power, I've found that a more mild intake with the correct size carb (not too big) makes a very pleasant all around powerband.

Got it up to 40mph on level ground and the same on a steep downhill, still feels like it still has some restriction (carb needs tuning for sure). That could be the airbox, the main jet or still a rev limiter in the cdi. Got a tiny tach to put on it and this will let me know about any cdi limiter. The roller weights (6 grams stock) feel too heavy during acceleration so the tach will help tune the variator also.

I'll admit I am biased towards small scooters and bikes, but I love this thing! It is super agile and has very good brakes.
It makes me wanna ride like I'm racing in a superbike championship lol! I can really push this little scooter to its limits and not worry about getting a speeding ticket. I haven't had this much fun since I sold my beloved Yamaha C3, and it's not even running optimal yet. I just sold my Lance PCH 150 and of course it was much faster, but not nearly as much fun.

I'll get some pics up in the next couple of days.
Title: Re: Derestriction questions
Post by: badmotorscooter on June 29, 2020, 10:35:30 PM

OK, looks like a 2010 Mio does not have a restricted cdi. The green plastic ring in the variator and the airbox itself are the only restrictions. There is a snorkel in the airbox and I ripped that out and opened the inlet area a little. Tuned the fuel screw from 1 1/2 turns out to 2 1/4.

It's gold now! 40 - 42 mph on level ground. No feeling of hesitation, the power band is smooth and it feels peppy. Installed a tiny tach and it hits just over 8000-8200 rpm's at top speed. About 7200-7500 rpm's during WOT acceleration, so the variator feels tuned pretty good overall. I might throw in some Dr. Pulley sliders which will probably give me another 2 mph top end. I had a hardly used 3-way adjustable shock from a CPI Oliver City 50 I had about 9 years ago, perfect fit. It firmed up the ride a without being too harsh (lowest setting 1) and the little Mio feels even sportier now.

The performance of the SYM Mio 50 has met my expectations. It doesn't have a high/low beam switch, but the headlight is about the most powerful I've seen on a 49cc scoot, just had to adjust it a bit higher. I wouldn't be too thrilled to ride on the highway, but it is more than adequate to scoot around town.