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My speedo is 10 mph fast on my new used bike so when i was taking off my rear tire I decided to count the teeth on my sprokets. The front one has 15 instead 0f 16, was this done for take off or top speed? Thanks
 

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gives you more top speed...it could be what is causing the speedo to be off but ive only seen it affect the speedo when changing the front sprocket...never went down on my rear sprocket but it is a good possibility...
 

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Fewer teeth on the front sprocket makes for quicker acceleration, and generally lowers your top speed.
 

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I went one tooth down on the front and it threw my speed-o off 10 mph. Also you'll see that your shifting alot sooner.
 

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Oh ya better to be faster then your going then slower!
 

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Yeah, it threw mine off a pretty good bit. I went down 1 tooth in the front. I also noticed that my bike gets hotter than it used to.
 

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From everything I've read and been told, going down one in the front is roughly equal to going up 2.7 (or about 3) in the rear.
 

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My 96 F3 has also a 15 and Im 45 in the rear. It threw my speedo off by 10-15 but I can figure about how fast I'm going from being used to it. Also, it'll make your bike sound like it's screaming. Mine does. I went back to stock, and the noise quit, then went back to -1/+2 and it's back to screaming like a bitch. gets annyoing on long rides. YEA! for ear plugs
 

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808 said:
gives you more top speed...it could be what is causing the speedo to be off but ive only seen it affect the speedo when changing the front sprocket...never went down on my rear sprocket but it is a good possibility...

Nope, it actully will give you quicker accel. and a lower top speed...
 

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cashflow911 said:
My speedo is 10 mph fast on my new used bike so when i was taking off my rear tire I decided to count the teeth on my sprokets. The front one has 15 instead 0f 16, was this done for take off or top speed? Thanks

Depends on the type of bike. Diffrent bikes read the speed from diffrent places so depending on your bike (dont know which one you have) it might read from the front wheel or might read from the gears....
 

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Casket Crew said:
Nope, it actully will give you quicker accel. and a lower top speed...
In a vacuum that is allways true, but not here on earth :twofinger

If the bike will not run to redline in top gear stock, its possible that going to a higher gear will increase the top speed. Reason: The RPMs will be higher at the 'old' top speed, and now there is more power to push the bike through the air. Then you have a higher top speed :cool:

Dont forget friction, and aerodynamic drag!
 

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you would seriously need alot more power than you could ever get with a few hundred more RPM to actually make you any faster. At those speeds, the aerodynamic forces are quite high, and even though your bike might now have the right gearing to use the full RPM range, the extra few horsepower you might actually get wouldn't be enough to overcome those forces.
 

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slingblade said:
In a vacuum that is allways true, but not here on earth :twofinger

If the bike will not run to redline in top gear stock, its possible that going to a higher gear will increase the top speed. Reason: The RPMs will be higher at the 'old' top speed, and now there is more power to push the bike through the air. Then you have a higher top speed :cool:

Dont forget friction, and aerodynamic drag!

He's -1 tooth on the FRONT, so actually it's quicker accel.
 

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slingblade said:
In a vacuum that is allways true, but not here on earth :twofinger

If the bike will not run to redline in top gear stock, its possible that going to a higher gear will increase the top speed. Reason: The RPMs will be higher at the 'old' top speed, and now there is more power to push the bike through the air. Then you have a higher top speed :cool:

Dont forget friction, and aerodynamic drag!

The only thing your missing from that equation is that the motor would have to produce more power... :)
 

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Discussion Starter #15
Its a 2001 cbr600 F4i I guess ill leave the gear alone. I was thinking it would make the top speed faster, if that was the case i would change it back. Drive to fast as it is. Thanks
 

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Casket Crew said:
The only thing your missing from that equation is that the motor would have to produce more power... :)
It does produce more power because its at a higher RPM.

Say that the bike "hit a wall" at 140mph. It just couldn't go any further due to drag. Well, you make the gearing shorter, and all of a sudden 140mph happens at a different RPM. A higher RPM.... Higher HP/TQ is available, and it can "push" you better through the drag. Now the top speed is 145 or 150.

(All assuming you weren't at redline when you hit the point where the bike would succumb to the drag)

It still accelerates quicker than stock, and has a higher top speed. It doesn't have a higher theoretical top speed though... When do we ride in theory though? I like riding in real life :twofinger

Physics people! Physics!
 

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Casket Crew said:
The only thing your missing from that equation is that the motor would have to produce more power... :)
Indeed. Gearing does not increase or decrease power, rather it redistributes it.
 
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