YX160 Running Issues

[phoenixpro]

I recently bought a project bike that just needed a few parts to get running. Its a PSTO TL160 with a yx160 engine that is brand new. I'm using a Mikuni 26mm carby and a blue alloy "performance" CDI. When The bike starts it is fairly rough, the exhaust gets hot and white smoke comes off the exhaust near the head of the engine. The oil level also drops, the oil cooler im using is properly hooked up as i've checked many different sources. Please help
Thanks
Paul

 

[my67xr]

Have you adjusted the mixture screw yet, it will need to be about 1 turn out
Is the foam air filter oiled with filter oil ?
I would suggest you get a new bigger pilot jet for the Mikuni copy 22/26, the standard #15 that come's in it is too small especially for a 160cc engine.
Oil level drop's, but does it come back to normal after sitting a while ?
The engine may need the valve/rocker clearance's done too, new they are a bit tight.
Make sure the engine is at TDC on the compression stroke when you adjust them, .003" on the inlet and .004" on the exhaust

[video=youtube;QJciyJRJh8Q]https://www.youtube.com/watch?v=QJciyJRJh8Q[/video]

 

[phoenixpro]

Thank you for the response, I will try to get some of the things listed done tomorrow and post here if I have any further problems. Yes the air filter is oiled and the oil level does go back to normal after sitting.Would this pilot jet be fine? Classic Honda 5's Australia

 

[my67xr]

Is this the carby that's on it china Mikuni 22/26 ?

Or this one china Mikuni 26/30 ?

No that Pilot jet is for a bigger Mikuni like the VM32 etc
This is the Pilot jet you need, the long one's at the bottom
Mikuni Carburetor Slow / Main Jets | Buy Online Australia at DHZ

 

[phoenixpro]

Its the top one

 

[my67xr]

Ok, just checking
It will have a #15 Pilot jet and #95 main, the #15 is too small for most 125's, a #20 will make it much happier
I would get a #97.5 main jet for it too just incase it is a bit lean in the top end.

 

[phoenixpro]

I changed the jets over today and did everything you said. It won't start easily at all and when it does start its still running very hot. I don't understand why.

 

[my67xr]

How tight are the bolt's/nut's that hold the carby, plastic spacer/insulator and manifold together ?
If you do them up too tight it can warp the mounting face of the carby?

Have you checked for a vacuum leak ?
Start the bike, and while it running spray wd40/degreaser or similar on the carby join's to spacer, manifold to head and see if it make's any difference the the way it idle's

How many turn's out is your mixture screw now, since you fitted the new pilot jet and retuned it ??

 

[phoenixpro]

Is it the screw on the bottom of the carb or side? There are two screws that can be adjusted.

 

[my67xr]

Side screw is the idle speed, bottom front one is mixture
Make yourself a tool like this is you don't have one, it will make your life a lot easier
Slip a small flat driver bit into a piece of 5mm i/d pvc hose and keep it for adjusting the carby mixture's

 

[phoenixpro]

okay, i'll have another go tomorrow. Thank you for tolerating my nooby questions. You're a legend in the mini biking scene

 

[fusionbet]

Yx 160 - YouTube

any ideas ppeople