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[randy50]

Ok guys after reading a lot of post I decided to post my first. I have a people 50 with 900 km. Im in to the derestricting thing. I replaced the variator shaft which was a big plus. Next I increased the main jet from .65 to .90mm. It will run good with this set up with the air/fuel screw all the way in.
I installed a K&N style open air filter and the engine run very badly but runs fine when I install the factory air filter.
My question is why does my engine only run with the air/Fuel screw all the way in?
What can I do to run the open style air filter?
Thanks

[zombie]

Because the 90 is too big. 80-85 may work better. The reason the screw is in : It is a fuel flow adjustment. The further you turn it counter clockwise the richer the idle mixture. That shows the main jet is too rich. The K/n wont work because your idle jet is too small. It leans the low end so much the scoot runs like cr@p. Make your low speed jet bigger, and the K/n, and the 90 main may work best!
Hope you get that...

[zombie]

What is your idle jet? It must be tiny w/ the 65 main! I would think you would need at least 25-35 pilot. I'm thinking yours may be 15-20?

[randy50]

Thanks Zombie, Didnt know I would have to experiment with the Idle jet also. Im sure its small but dont know the exact size. Gonna order some main and idle jets of various sizes and play.

[randy50]

Drilled out the idle jet today to .35mm. Installed the open air filter and after a little adjusting the bike runs fine. Its louder than it was with the stock air filter but its worth it because of the power increase. Man these engines are touchy.
Thanks for your help.

[zombie]

VERY touchy! Do yourself a favor... Buy a new spark plug to do a WOT plug reading (chop). Your plug tip should be a medium to dark brown. NOT WHITE. Run at wot for a minute, and shut it down coasting to a stop. Tuning the carb is a pain but rewarding when you get it dialed in.
Stick around. Your experiences will help others.