19k miles and always use 87 since new.. The bikes are designed with high compression BUT made to do it on 87(newer bikes are designed for 91up because of more timing and even HIGHER compression than the f4i).

Compairing a high performance car to a bike is applies to oranges.
I get worse gas mileage on 93 than on 87..
Bike makes 97hp at the tire on 87 so i have no complaints.

 

^^yeah these threads are dumb lol. i almost feel bad contributing this much.

 

I don't know what difference it makes but I use 91 anyway just because it's like 10cents more/gal anyway.

 

How much more is premium? 5-10 cents? So you're talking NO MORE than 40cents more per fill-up difference (as opposed to 87), and thats worth the peace of mind to me...even if it doesn't improve "all that much". I see no reason not to put 92-93 in.

 

I actually doubt itll improve performance at all. Ive run both premium and regular, no differencein performance. And its pretty much agreed upon that f4is get better fuel economy on 87 compared to 91/93. But if you want to throw your money away, go for it.

 

Well if the bike dosen't need 91 and won't add timing to use the 91 then it actually hurts things in the long run. Since higher octane takes longer to burn and the combustion has been optimized for 87 then all the fuel dosen't have time to burn when using 91. This reduces power [and milage] and increases the carbon deposits left in the cylinder and exhaust.

 

Thats like putting 93 in your corrola.

If the bike is tuned for 87 the only thing your doing is most likely DECREASING the MPG and performance.

I guy on another forum said he made 2 more WHP on 87 over 93. That doesn't say everything but it does reinforce my point.

 

91+ always. the Compression is way to high if you run regular its going to predetonate. And plus its only like 60 cents- dollar difference per tank. Why risk it

 

How is it going to detonate if its designed for 87 ?

 

I don't own a manual please scan the page that says its designed for 87. high compression always runs into detonation issues when running 87. compression is still compression the amount of pressure in each cylinder is still the same. You wouldn't run regular in a ferrari engine with 12:1 cp would you?

but realistically are you that cheap that you want to save 60 cents a tank?