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I have the new ninja 300 and want more speed out of the 115 max I've heard it go up to. How do I increase it with my sprockets? Is it more teeth or less?
Gear ratio upgrade for more speed?
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Adding a 15t front sprocket should get you approx 124 mph @ 12500 rpms.
Adding a 15th front sprocket and a 41t rear sprocket should get you approx 127 mph @ 12500 rpms.(providing the 300 can turn that ratio past 12k)
Adding a 15th front sprocket and a 41t rear sprocket should get you approx 127 mph @ 12500 rpms.(providing the 300 can turn that ratio past 12k)
What RPM is it running at 115? You need to look at a dyno chart and see where it's running vs where the power peak is.
If you are past the power peak. gearing up (reducing teeth on the rear or adding on the front) may get you more top end.
If you haven't reached the power peak at that speed, gearing up won't get you more. At that point you are running up against an amount of aero drag that the power can't overcome. In that case, gearing down may get you more top end.
If you do gear up to get more top speed, but you'll feel a loss of acceleration. You will also drop your highway cruise RPM.
If you gear down you'll increase your acceleration and also your cruising RPM.
Jay
If you are past the power peak. gearing up (reducing teeth on the rear or adding on the front) may get you more top end.
If you haven't reached the power peak at that speed, gearing up won't get you more. At that point you are running up against an amount of aero drag that the power can't overcome. In that case, gearing down may get you more top end.
If you do gear up to get more top speed, but you'll feel a loss of acceleration. You will also drop your highway cruise RPM.
If you gear down you'll increase your acceleration and also your cruising RPM.
Jay
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Ya I figured that, I just bought this for a short time to break in and teach my wife on till its paid off to buy a bigger bike. I was jut trying to squeeze something more out of itmorgan46 said:
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Is it worth it?
It all depends if... $20 and 45 minutes of installation time, longer 1st gear, approx 10 extra mph(top end), slightly better mpg and 1000 rpms lower cruising rpms is worth it to you. Also the speedo will read more correctly. In stock form the speedo is off about 3-4 mph. This has been confirmed by GPS to be within 1/2 mile of correctness.
For those who have done it for the Ninja 250, will say it was one of the best mods they've done.
Surprisingly the same 15t front sprocket that fits on the 250 fits on the 300.
P/N# JTF516.15
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But gearing up mite make it better ( Lower RPM ) at highway speeds?
:thumb::thumb:.......
If you want more than 115 get a bigger bike.
Splat.....
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I'm guessing the bottom end is to low geared anyway.
I know my 650 sure is n when it's time for a sprocket/chain change out I am going 1 tooth diff on the front.
:dance::dance::dance:
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But.... U probly wanted a faster take off at start n the next couple gears? Maybe u run track.
Myself.... I just go for nice scenic rides, and play a little on the mountain twisties.
No track
Myself.... I just go for nice scenic rides, and play a little on the mountain twisties.
No track
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The Ninja 250 nor the Ninja 300 were designed with top speed in mind. The were designed with ease of drivability and economy in mind. Needless to say neither one is endowed with front end lifting torque, unfortunately they are really under geared in stock form. The Ninja 250 is more than capable of utilizing a 15 tooth front sprocket effectively without a loss in torque or HP. In fact the bike's first gear becomes much more useable and the overall reduction in rpm speed is much less stressful on the engine while maintaining maximum mpg.
There are a lot of Ninja 250 owners that have changed their sprocket from the stock setting (14/45) to ratio's ranging from 15/45 to 15/39. Some have even went as far as installing a 16 tooth front sprocket ( requires modification to the sprocket cover) 15/42 & 15/43 tend to be the optimal setup, providing good acceleration and top end speed. Many who race the Ninja 250 are using a 15 tooth front sprocket.
The Ninja 300 has 10% more HP and torque than the Ninja 250 in the low rpm range and therefore it's much more capable of utilizing small gearing changes, while maintaining max HP with increasing top end speed. (albeit 5-10 mph max). Any additional engine stress that would normally come with higher rpm speed, is reduced by lowering the rpm speed, while still using the available HP to it's potential with 15/42 sprockets.
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