Honda Motorcycles - FireBlades.org banner

1 - 16 of 16 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter #1
Wondering if since I got a f2 carb on my f3 motor will the scoop/ram air still work and is it OK to install a jet kit without any complications? Also can a fuel pump be used with the carb and motor setup?
 

·
Registered
Joined
·
234 Posts
Im not sure the F3 air box will bolt to the F2 carbs. You might need the F2 air box. And then put the F3 ram air stuff on it. Minus the low speed circuit which alot of F3 rider eliminate. I would think you could use a fuel pump. Probably have to because once you get some air force in there it might not let the fuel flow so a pump would counter act that......I think.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #3
Thanks for the reply. I have the f2 box but would like to just change the top part with the f3 box so that the ram air can work. I'll look into getting the fuel pump. Will eventually get a stage 1 jet kit for the f2 carbs though to try and compensate for not having the f3 carbs on the f3 motor.
 

·
Registered
Joined
·
234 Posts
The F2 top half of the air box has the intake tubes mounted to it. The F3 doesnt, but the F3 tubes are mounted on the ram air part, I believe. So I figure you could use the F2 complete air box minus the tubes. Something like that. But on a side note, there was only 3 or 4 mph difference in top speed between the two bike when new. So how much does the ram air really help. Plus the F3 was lighter and a little more compression with bigger carbs.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #5
Thing is I had a problem going into 3rd gear when using the f3 ram air with the carbs before because the bike would loose power. So once the ram air was removed the bike ram properly. Am figuring more or less that was due to the lacking of the fuel pump because I was just running a gravity feed. So thinking about adding back the fuel pump and ram air.
 

·
Registered
Joined
·
193 Posts
The f2 and f3 airbox comes apart in 3 pieces, lower(which bolts to the carbs, middel which bolts to the lower and top which botls to the middel. . you can change the the airbox but you will need the top and middel as the airbox structure from the f2 and f3 differs but the lower parts of the airbos are the same on all f2 and f3. Now i dont know if you have a f3 frame or a f2 frame but the ram air wont fit on the f2 frame also if you use f2 carbs on a f3 then you will have to jet the f2 carbs as per the f3 which would be 138 mains,38 pilots and depending on your exhaust maybe a few shims under the needles . .another thing the f2 carbs are alot better and easier to tune and if you install the same size jets as the f3 carbs have into the f2 carbs your bike will run alot better .
 

·
Registered
Joined
·
22 Posts
Discussion Starter #7
OK thanks a lot for the info. Its actually a f3 frame. The bike ram ok with the f2 carbs and jets but just notice that the rpm never went pass 10k and wondered if that was the reason why. The exhaust I got on right now is a stubby.
 

·
Registered
Joined
·
193 Posts
If Its a f3 frame then your set!honestly I would use the f2 carbs as there are no hoses that need to be ripped out and no ram air that needs some tweaking another thing if you use the ram air you will have to use a fuel pump because the speed at which the air enters the air box on an f3 is a lot faster than of an f2 the reason for the fuel pump the fuel need to travel exact same speed into the carbs as the air does otherwise you will get a lean mixture with f2 you don't have to use a fuel pump as as the air in the f2 airbox is being sucked in not forced in and that 10000rpm issue you are having is because of the mains. ..put some 138s in the mains and shim your needles with say maybe one waher and go from there I can guarantee your bike will be a lot better and feel a lot stronger.
 

·
Registered
Joined
·
193 Posts
Another thing i forgot about.if you are using the f2 carbs remeber to disconnect the tps sensor as they are only needed when using the f3 carbs.another thought for your bike not going past 10000rpm check you have a clean filter aand there are no pinched hoses anywhere fyi a tps sensor could also be the culprit for not revving past 10000rpm.
 

·
Registered
Joined
·
193 Posts
A f3 fuelpump can only be used if you have the f3 cdi . . . so make sure tou have a f3 cdi and not a f2 cdi otherwise the fuelpump would not work and would be useless.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #11
Thanks for all the info. I need to check if is a f3 cdi on the bike but should be. The thing is 10k rpm would respond like 14k rpm but the tach just shows the 10k. I'll use your suggestion and change the main. Question can just the fuel pump prevent the fuel from leaking into the oil. Because when I leave the bike overnight and check the oil it smells of gas!
 

·
Registered
Joined
·
22 Posts
Discussion Starter #12
In order to stop the oil from smelling like gas I had to put a small lock off on the bike below the petcock because seems like the petcock not stopping the fuel when it's switched off.
 

·
President: Team Full Chat
Joined
·
8,119 Posts
Fuel in the oil is a tell tale sign of leaky needle valves in the float bowls. When they leak the bowls overflow and the fuel dumps into the intake tract.
 

·
Registered
Joined
·
193 Posts
I c what you mean . . . .then it could be that you have a weak tacho signal coming from your cdi.mine also did something similar,my tacho needle would stop for a second or 2 on about 11000rpms and the just jump to to which ever revs it got to after the needle stopped. . so i found the signal wire going to the cdi and i snipped it off say 2 inches from the cdi so i just solderd on a new piece of wire and just tapped it up alongside the loom for the bike and ian is dead right check your float bowls i bet they are the culprits. .
 

·
Registered
Joined
·
193 Posts
I Mean you have to check the needle valves in the float bowls like ian stated.
 
1 - 16 of 16 Posts
Top