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Old 10-17-2013, 10:00 PM   #41
Water Warrior 2
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Re: 16T vs 15T sprockets

:lol: :lol: I think we have all been there at least once or twice.



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Old 12-31-2013, 04:09 AM   #42
scott103
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I have an 09 with 14xxx? miles on it, and have put at least the last 500 on with the 16t i upgraded to. I can't tell if it hurt gas mileage, because i don't pay that close of attention, just put in $9-10 within 40miles of hitting reserve, but it seems like i've been going farther. I rode the 15t on the interstate a few times, then experienced a night and day difference with the 16t. I'm comfortable at 65-70, can still hit 75+mph, with the 15t i didn't like going over 60 very often.
The biggest benefit I found is that I can cruise on 40-45mph limit streets in 4th gear without feeling like i should hop up to 5th. I may be burning a little more gas in 4th at 45, but in 5th, i had to downshift if i slowed down at all or wanted to accellerate.
I also feel that 1st gear is finally useful for parking lots, and i can use 2nd gear in residential areas, whereas it sounded like the motor was revving pretty high at 25 in 2nd with the 15t.

I weigh 170ish, and think my bike may have been jetted in the past, so that might be why i don't feel there is a loss in power-my bike is also NOT coldblooded in 40 degree weather
I give the 16t two thumbs up, but weight or jetting could be a factor.
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Old 07-09-2015, 07:45 PM   #43
FLAJIM
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Bought the bike for my wife to learn on. With the 16T she using all the gears longer which will help her transfer to a larger bike down the road. For me, at 235 I can ride at 55 mph 4500 rpm and getting 68 mpg. Sorry but I just don't like taking this bike faster than 55 but that just me.

Be Safe JIM



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Old 07-09-2015, 10:40 PM   #44
spldart
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I installed the 16t sprocket a while ago. I'm loving the lower rpm at freeway speed and my mileage is unchanged. 68 to 80 mpg. 70 to 75 seems to be my average. Before and after
the upgrade.
My thinking is this. As FLAJIM mentioned you now only turn 4500 rpm to do 55 mph.
This equates to one very important fact....
Lower ring speed.
Winding out a motor is bad for components and one of the important ones is your rings...
...And your valvetrain... Anywho...
We know redline is prolly 8k to 8.5k rpm but the engine can't live long at high rev.
So this mod and keeping your speed below 65mph is a great way to increase longevity
imho.
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Old 07-10-2015, 05:41 PM   #45
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If I remember correctly the British auto industry would list piston travel in there advertising and owners manual. Never thought much of it at the time but it makes sense from a reliability standpoint. Yeah, we are going back a few decades. Modern engines in cars don't seem to worry about piston travel. Better materials and oils make things last longer. Oops, should include much better research and design too.
What was once considered an exotic design such as roller cams, overhead cams and roller rocker arms were for the rich and famous willing to spend the $. These designs are very common place now for their longevity and reliability.
The GZ may suffer from an older design but it is also the reason it is a popular machine. It is much simpler and fits well with it's target market.



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Old 07-10-2015, 09:45 PM   #46
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One thing between bike and car motors... Rev's
Piston ring speed peaks at half way between top and bottom stroke positions.
It is not only a matter of stroke measurement but the revolutions per.
Both rpm and stroke length are involved in calculating ring speed.

Why do I now feel sullied after that statement?
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