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15 T sprocket

So between -1 and +1 front sprocket you're guessing top speed would be the same??

What about between -1/+2 and +1/-2? Same top speed too? :BLAA: no way!!!

We're both guessing here, but short of confirming the exact top speed numbers which I believe we all could care less about, the bottom line is simple: -1 in front means that you will be going SLOWER than stock for any given RPM (but you will reach that speed faster).... I think we all agree on that.


I have to disagree. My previous FZ6 was -1 +2 and it would redline in 6th gear. With the speedo-healer showing 140 (139.3 actual) as top speed. With stock gearing the top speed was slightly lower, as it would run through 5th gear and redline but lose pull after shifting into 6th.


And even with the -1+2 my mileage barely dropped. :BLAA:
 
For what it's worth, I went ahead and built a spread sheet to calculate what the change in final drive ratios would be comparing the OEM 16-47 combo to 15,16,17, @ 47 tooth rear and 49.

15/49 makes your gearing 10% shorter.... that means you'll turn 10 higher revs for a given ground speed, through every gear. Instead of 7K at 70 in 6th, you'd be turning roughly 7700.

All the other combinations are lower change values from the OEM 16/47

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I have to disagree. My previous FZ6 was -1 +2 and it would redline in 6th gear. With the speedo-healer showing 140 (139.3 actual) as top speed. With stock gearing the top speed was slightly lower, as it would run through 5th gear and redline but lose pull after shifting into 6th.


And even with the -1+2 my mileage barely dropped. :BLAA:

What do you disagree with? That doing -1/+2 will decrease your speed for any given RPM?
You could not reach 140mph with stock gearing? weird...

You took a pic of your speedo while going 140mph? How has the pic in your avatar the same exact time and mileage?
 
What do you disagree with? That doing -1/+2 will decrease your speed for any given RPM?
You could not reach 140mph with stock gearing? weird...

You took a pic of your speedo while going 140mph? How has the pic in your avatar the same exact time and mileage?

The original post was losing TOP speed. No one is questioning that you will be doing less mph with -1 gearing vs. stock gearing in each gear.

I could reach 140 (actual speed) indicated was 158 with stock gearing it just wouldn't keep climbing after that. Hence the comment that IMO you don't lose any TOP end by doing -1 or even a -1+2 sprocket change. There's only so much power to propel the bike to those speeds. If anything the top speed may be higher with a -1 sprocket.

The pic was taken while the bike is stopped, that's why the RPM's are zero. The speedo healer has TSM or top speed memory. My goofy buddy did a photoshop and changed the numbers just for giggles.

:Flash:
 
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And just to throw in another factor.... The top speed when the bike was naked dropped to 136. ;)
 
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For the sake of conversation..... what altitude were you at, when doing these top speed runs? Colorado?

Less than 1000 ft. I lived in Georgia for a while. I doubt it could match that now as I'm at a base elevation of at least 7500 ft to a max of 10,500 in my usual riding area.

On a closed course track of course. :D
 
I went with 15T and 48T instead of just the 15. IT IS ABSOLUTELY NUTS.
I was popping it up in first, shifting into second AND third.

Top speed? I hit 135 gps confirmed with this sprocket setup at the top of 6th. And I weigh 300lbs.
 
What was your top speed before the mod?

The fastest I ever went with stock gearing was 125mph, on the same road.
The road only has a straight of 0.81 miles and I've never really tried going that fast anywhere else.
It's easier to get to redline with the shorter gearing
 
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