two questions

1, in the sticky it says to use 87 gas but the sticker under my seat (06 F4i) says to use 91 min, i have been putting 94 as much as i can, in, so far, but am i wasting my money?

2, what size of plug is good, i can get NGK ones from the dealer for $10 a pop but i have a feeling they are robbing me. is there anything better then the single pole NGK ones out there? maybe the botch +2 or +4? or even the NGK split or something.
how about wires? normally on a car when ever i changed the plugs i switched the wires too but no the bike i got 25K on it, i think its a bit too soon, but then again its an 06 so its almost time.

in puts?

 

Yes. 87 is sufficient.

IF the shop is suggesting the OEM NGK plug (IMR9C-9H), the going rate *is* about $10/ea.

 

You don't replace wires you replace coils, and I would just check the coils, look for carbon tracking. And your lucky about the plugs, Honda near me wants $21 a piece for iridium plugs

 

You don't change coils either unless they stop working, which is pretty much never. Order plugs online as dealerships always charge way too much.

 

1+ boredandstroked

 

The sticker says 91 RON, which is 87 in the US using a different method. It should say on the pump which method they use to compute the octane of the fuel. I don't know how they figure it in Canada, so you will need to look.

 

i think canada and us use the same method of calculation

(R+M)/2 which is the avrage of R-research + M-motor devided by 2, not really sure about the math for each. but all pumps in us and canada use the same method, i belive europe uses the same but the EU spec engines are normally 'tighter' due to the higher emmision laws.

in either case, can some one please lift up the seat and look at the sticker to see if they say same thing or not.

 

All F4i's are a minimum octane of 87, You can put higher octane in but you will not get any performance gains or fuel savings, So you are basically just throwing your money away.

My bike actually gets better gas mileage on 87 then it does on 94.

 

The higher the octane the slower it burns. Hence the less knocking and the term ‘anti knock rating’ or more commonly known as octane.
It is possible to get better gas mileage from a lower grade gas as long as you run on open loop. And/Or you don’t have an O2 sensor somewhere before or after the cat. The closed loop engines look at how much fuel is ‘left over’ after the combustion and will keep dialing down the gas till the knock sensor goes off then it richness it a bit. A proper California standard engine will do this all the time. So you burn more or less gas depending on how much throttle you are using, engine load, speed, rpm, all sorts of different stuff.

Now that being said, an open loop engine such as the old school carb ones or something like that, will look at less sensor inputs, and will go into a pre determined database to put a bit of gas or a lot of gas depending on what the driver is doing, and it doesn’t look at the result of these actions to adjust the fuel/timing.

That’s why all these VVT engines get such good gas mileage and more power for less gas. They constantly adjust the timing, the valve position and even open/lift duration, in some case they can even shut down a valve at an rpm range or open it after some to give you the best performance for the least amount of fuel.


For example, the Honda i-VTEC series use the VVT as well as an electronic lift controller to actually move the cam shaft over so the lobes that touch the valves are different at different RPM.

So bottom line my friend, when a manufacture tells people to use a grade of gas, they have done all their calculation based on that. So if you go ahead and put something else in, you are messing with all sorts of numbers that the engine now has to figure out using all the sensors.

That’s all I got.
Not all of this will of course be applied to every engine, my lawn mower doesn’t care if I put in 85 or 94 or 104, and it will burn it all the same. But if I put 85 in my turbo charged STi then ya ill feel the difference.