Why it is there?

Is it normal to have hole under my engine sized like small fingernail head. where the engine halfs meet?

But i have full power 1994 that hasnt any restrictions?

Ok i will buy athena silencer because i need it.

Where i can buy carburetor main jets to my dt 125r with 28mm

Yes. What is good budget exhaust and it is worth buying? Power increase?

I meant like do they give low end torque or throttle response?

Are they worth buying? Low rpm torque?

Does Boyesen Reeds give more power?

So i buy avon trailriders or full street tires?