I've read all the posts about replacing the front and rear sprocket to increase speed, but I am neither a stunter wanting to pop wheelies, or a racer wanting to go the speed of sound. I'm just a guy that bought a 05 f4i to replace his 02 sv650s. I got used to having power in all gears at a flick of a wrist. and I want that same effect from mt f4i. Is changing the sprockets -1 down + 2up going to give me the desireed effect?

 

yes, but you will have to switch gears more often and will be at a higher RPM when you're on the highway, your speedo will also be off by about 12% or so.

 

I've read that my speedo will be off in previous post, but someone spoke of a way to fix that problem. Also I don't understand how swapping out gears would effect my speedo. 10 mph is 10 mph no matter if your on a bicycle or a motor bike, right? Lastly, at present stock form I'm only getting 140 MPG before my fuel indicator comes on, regardless of if I ride hard or slow. Whats up with that, is that what you guys are getting?


P.S. Great web site!

 

Speed on the CBR is measured from the front sprocket not the front tire.

When you change the sprockets 14% the speed is off by 14%... it does the math on sprocket rotations, times by the rear sprocket (ratio front to back) and then times by the circumference of the tire times by minutes per hour...

A speedo healer will take the pulses, sort them out and send the correct speed to the speedometer/odometer... about 100$

I'm currently running -1,+2 on an F4 which probably has simular gearing to the F4i... if so check out my photogallery for charts showing actual road speed for rpm for various sprocket configs.

 

for the street that gearing is good.

 

ninetyfivehp, which gearing are you refering too? the stock or-1 +2? Also any feedback on the MPG issue?

 

-1 +2, bettter acceleration and toque but a loss of top speed, but the trade off is definitely worth it imo

 

-1/+2, I think is over kill.... yes you will be getting better 0-60 but once your buddys decide to cruze at 120 130 then your in ther dust and your night is over! if you want the tourqe the V-twin puts out... get a RC-51 cause the jap inline 4's dont have **** for low end tourqe! [:@]

p.s. I too went from a bike with massive tourqe and its just somthing your going to have to get used too.. i currently have stock gearing and i think its the best blend of top speed and acceleration..

 

I'm currently rolling awith -1 +2 gearing. its how i bought the bike.

I've gotten used to the fact that my speedo's probly around 10mph or more off at freeway speeds.

Gas mileage i see around 130-150miles before the reserve meter comes on. i thought it was strange untill i realized i was only putting in around 3.5 gallons of gas whenever the reserve come on. There's still around a gallon and a half of fuel left in the tank when i fill up( usually fill up wne im a bar or 2 down on the reserve. Maybe the shorter gearing messes with the reserve range calculations. Doing the math i m getting around 42mpg, thats around what people are getting on stock bikes and thats with me getting into it a little bit here and there.

My biggest problem with the gearing is not having an entirely accurate idea of how fact im going, and having the motor cranking at 7-8000rpm at freeway speeds.

There's still a good lack of torque in first gear until im going around 30mph (over 6000rpm), even with the gearing i still have trouble keeping up with my brother's nt650 in fast first gear takeoffs unless i rev the bike and slip the clutch a considerable amount, i end up having to make it up late in first or in second gear.

IMO gearing can help a bit with giving the bike some lower speed power, but its always going to be a peaky 4 cylinder no matter how you gear it, and i find the tradeoff in freeway cruising rpm not worth whatever slight advantage i have over a stock bike in first gear. So im going back to stock 16-46 sprockets.

 

Very interesting info Jason, and spdrmns if I cruise at 120/130 MPH I'd loss my CDL licence and wouldn't be able to pay for the bike. It's a rare occasion when I go past 100MPH and if I do it's to leave some tali gater in the wind. Comfort and a low gear power are more important to me.

What about different setups, such as going down one on the front sprocket only. Will that make a difference? Would my speedo still be off? Or should I leave everything stock and replace the can/ and be happy with what I've got.

You guys are pretty freakin smart!!!!!!!!!