At the moment I still have problems with the cylinder head of my GZ125. After much back and forth I have to leave the head installed this season, but does not want to expose my many tours. At the same time, this extreme clacking is very annoying.. Now I have asked myself: could you dampen the noise of the engine, especially of the cylinder head, with a thicker oil? And with this possible problems better save? After a.. in case the engine ran already for a year to 10W5 0, and that, with regard to its problems, quite well My engine uses normal 10W40, currently the engine is running on Castrol 4T 10W40 motorcycle oil. The option would therefore now be to mix the oil either with 10W50, or completely replace it. How effective would such a thing be? Or would I be advised not to?