front sprocket power influence

[clemmr211]

I recently put a new motor in my bike, a 2001 ZX6R.  When taking the last motor out I was not able to get my front, 15 tooth, sprocket off... so when I put the new motor in I put on a 16 tooth front that I had as a spare.  I had planned on going down a tooth or 2 in the rear anyway so I figured I'd give the 16 up front a shot.  Well I knew the bike would pull differently, but how much of a change should I expect?  I had it out this past monday at Summit Point and it seemed pretty down on snot (the nice pull I'd get from 12-redline, although over all my laptimes were only 1-2 seconds off of normal (and I can attribute some of that to it being not raining and d*mn hot ;) ).  Will going up one tooth in the front make this big of a difference or should I be looking for possible problems with the motor?
Thanks in advance
Ryan

[rick]

Well, a larger front sprocket would give you a higher top speed at the expense of acceleration. Going up 1 in front is like going down 3 in back. Most people, at least to start out, go the opposite direction.

Anyway, I'd expect it to be pretty noticeable. :)

[clemmr211]

....Anyway, I'd expect it to be pretty noticeable. :)

That's what I'm hoping to hear more of...  

[spyderchick]

What you need is a good gearing chart for your bike. You might be able to find an engineering type who has an Excel file you can reference. Good luck! :D

[clemmr211]

What you need is a good gearing chart for your bike. You might be able to find an engineering type who has an Excel file you can reference. Good luck! :D

I do have one of those sheets and after plugging in my numbers it told me that 3rd gear experienced a 23% RPM change, and that was the gear I was most concerned about getting a little more out of.  I kinda new that it would be a significant change, but wanted a quick sanity check from some others about how much can be felt changing the front and leaving the rear as is.

[tcchin]

Gearing has no effect on power. Gearing scales rear wheel torque and, inversely, speed. As power is defined as work per unit time or force times velocity, power is unaffected by gearing.

As you've changed the final drive ratio and not the internal gears themselves, your gearing will be subjected to the same ratio change regardless of which gear you're in. That change, by the way, is the number of teeth by which the new sprocket is larger than the old sprocket divided by the number of teeth on the original sprocket, or 1/15, or 6.7%.

[unforgivenracing]

I like 16 fronts rather then 15's but I don't go well on the idea of a smaller rear to make up for the chain lenght.  Add a link if nessasary for more room to ajust.  Stay with the same rear your used too and try it out first.  

I recently put a new motor in my bike, a 2001 ZX6R.  shot.  Well I knew the bike would pull differently, but how much of a change should I expect?  I had it out this past monday at Summit Point and it seemed pretty down on snot (the nice pull I'd get from 12-redline, although over all my laptimes were only 1-2 seconds off of normal (and I can attribute some of that to it being not raining and d*mn hot ;) ).  Will going up one tooth in the front make this big of a difference or should I be looking for possible problems with the motor?
Thanks in advance
Ryan