Hey, just bought my 02 f4i.

It was babied by the original owner and it shows.

However, when I was leaving.. he told me since day 1 he put in 93 octane.

Should I continue to use 93? Or run it low then switch to 87?

Will it matter?

 

The manual says 87. Try it, If it knocks go a little higher till it doesn't. Run the lowest you can, starting with 87.

 

^ yup. Search on here about it theres a bunch of threads or do a google search on octane ratings and youll realize its almost always unnecessary for the f4i. The bottom of the first page and the second page of this thread has a discussion about it as well.

https://cbrforum.com/forum/f4i-main-...on-kit-122109/

 

Alright, well my question would be...

Will it do any damage if I continue to run it on 93?

Thats my main concern.

I will wait until the reserve kicks on and then go fill it with 87 if you think thats a better decision.

 

Oh no it wont damage the bike but if you dont need to spend the extra money on 93 why bother. With these small gas tanks its probably only an extra $1-2 a fill up but youre not getting any added benefit or performance from it if your bike can run on 87-89 so its just not necessary thats all. Its also inefficient if youre not burning the fuel completely and could cause carbon buildup.

 

Not another octane thread. Search it's been gone over and over and over.

 

You have to check and make sure you don't have any power adders that has a tune on it. Correct me if am wrong but I seen people buy used bike, fully tuned when most people don't know and run 93. Your bike will run like crap and possible could damage something in the long haul if not ran for the correct tune. If she is stock or just filter/slip-on then nothing to worry about!