Normal oil is 10w.
15w will firm up the front end and in my opinion makes it feel much more stable and predictable.
You will feel the bumps a little bit more though, so if you reckon you'll be using dodgy roads then maybe standard the 10w oil will be better for you.
To be honest i reckons it's a personal thing, although if you are a lightweight rider then stick with the 10w, but if you are a heavier rider or take luggage or passengers on a regular basis then i'd suggest 15w is the way to go.
NOTE: Your bike is an FZS600, not an FZ6.
15w will firm up the front end and in my opinion makes it feel much more stable and predictable.
You will feel the bumps a little bit more though, so if you reckon you'll be using dodgy roads then maybe standard the 10w oil will be better for you.
To be honest i reckons it's a personal thing, although if you are a lightweight rider then stick with the 10w, but if you are a heavier rider or take luggage or passengers on a regular basis then i'd suggest 15w is the way to go.
NOTE: Your bike is an FZS600, not an FZ6.
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