Bogging issues! Help

[SkeetSkeet]

Yes i'm a newbie but i have worked on 4t scooter more than 2t.
Anyway i just bought a 96' Honda Elite Sr50 with a SA50p motor (DIO i assume) and i'm having bogging issues!
I bought it dirt cheap because the PO said it no longer went up to the right speed after the muffler rusted off. He then took it to a Honda mechanic and they put on a new muffler.
It's still not running correctly, as it'll get up to 10mph and then bogs. I assumed the new muffler had too much backpressure so i bought a performance pipe (PG V8). Installed that and that got me up to 20mph but it bogs after mid throttle.
So i took off the air filter to see if it ran better and it did but still bogged a little more than 20mph.
Now im thinking the main jet is too big as it has a #78 jet which i don't think is factory.
Now i have a #75 jet in the mail and also a #68 jet (stock) just in case i decide to put the original muffler back on!

The real question is what jet should i use with the v8 pipe and would i have to buy a uni-filter for more air?

p.s. i'll eventually put a bbk on it or just sell it after its tuned!

[SkeetSkeet]

Problem solved!
it turned out to be the air/fuel mixture was 2 1/2 out instead of 1 1/4 turn out!
Took it for a test ride and got way past 35mph mark!