I have a new yamaha yfz 50 that ran great when picked up and great for half of the throttle. As I backed off the throttle screw however it starts puttering around half throttlw and wont smooth out. Anyone have any pointers to look at before taking it back to the dealer?

 

For a brand new 2021? I'd go right back where you bought it from and have them look at it. Seems like it should have some sort of warranty I would imagine.

 

It has a 6 month warranty, i have had it 3 weeks. Planning on calling tomorrow, just seeing if there is something I can check. Or if that is how they run...

 

Does it get any better if you put the adjustment right back to where it was before you messed with it?

 

I put the limit screw in and adjust it to where it will run smooth. About half of the available throttle throw.

 

So I called the dealer and there is a limiter plate installed from the factory that limits it to 4500 rpm give or take. Take the plate out and it lets it up to 7500ish rpms....