[nemom109r]

If grinding, drop and check your oil. Also cut open your oil filter and check that.
They would be the firsts step I'd take if I heard any "grinding" as such.
Hopefully comes out clean.

 

[nemom109r]

Magnetic plugs do help.

 

[nemom109r]

Shift 1 -> 2 like you mean it. Try shifting at slightly lower revs too.