i noticed that my engine was smoother between 4-5000rpm, before i did an oil change.
previous had 10w40 in it and now i went for motorex 15w50.
now the bikes pretty vibey that it bothers me...
can an oil change to a different viscosity cause this?
i also suspect some oil consumption with the 15w50, didn't notice this with the 10w40, but didn't do many miles with the 10w40.
i bought the bike like this and changed oil after about 1500km.

valves make no sound, idles well without any extra noises. runs smooth upto 3-3500rpm

bike has a pipercross filter, decat original exhaust, fuel mod, fresh spark plug.
(come to think f it, i did change to CR7EIX, coming from original spark plug)

can't really say when exactly it changed...

any suggestions bases on real life experiances.
i did come up with the idea myself to change il back to 10w40, thank you

ciao, Hannes.

The ambient climate in Belgium isn't known for being hard on oil grades, in fact you could use several differing grades in theory. If you bought cheap oil / supermarket own brand then maybe you have inherited a problem albeit supermarket oil is usually unlabelled quality oil.

Something, coincidentally, else has changed if you have a distinct vibration.

Have a thoroughly refreshing read of this and also discover which bolts are loosening off on your chassis or other mods are effecting smooth running.

https://wiki.anton-paar.com/en/engine-oil/

although this earlier post sounds familiar ;-)

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I have a lot of growing up to do. I realized that the other day inside my fort.

So i took the touratech handguards off and installed the genuine bar end weights back on, the black heavy ones.
seems quite acceptable now.
i was planning to for the brass in-bar weights, but i saw the inner daimeter is very narrow after the first part where the heavy black weights screw in.
first +- 3cm is threaded for the weighst and if i should make some brass in-bar weights, they will be so small in diameter, that they won't have any effect anymore... don't know if i have the original handlebar.
still if those black weights screw in ,it must be the std one then...
any suggestions?

playing with the fuel mod dodn't change anything.
checked timing of the cam chain, all is good.

I guess if your original bar weights are screwing in then your bars are probably original too and in that case Kev's brass bar weight mod may work for you. Some people have filled their bars with kids play putty to add more weight whilst at the same time reducing vibrations.

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I have a lot of growing up to do. I realized that the other day inside my fort.

I put garden hose in mine and filled that with silicone

all i could fit is maybe a fuel hose, really don't have much inner diameter left... maybe about 15mm inside.