First ride-15t sprocket

[wild-bill]

I took a 10 mile ride to test it out. First gear is a little more useful. I shift into 2nd about 2/3 through an intersection instead of halfway. At 70-about 75 indicated, RPM went from 9000 to about 8400. And I can stay in each gear a little longer. It seems acceleration did not suffer enough to hurt anything. The only thing I don't like is I have to go faster to get out of the buzz zone(7,000-8,500RPM). I used to get up to 65 and it would go away. Now I have to stay above 70 for the engine to smooth out.

[DaBlue1]

A 42 tooth rear will make you rpm's drop so 70 mph indicated will be approx 7000 rpms. 6.5k -6.8k will be the new "no buzz zone".

[slolane]

Agreed, I just did mine at the end of last year and ended up with 15/42 also... for general riding and better on the highway this setup is great. Just my .02

[Yasko]

You guys really enjoy the 15/42 for normal everyday ridding, or is it for more highway rides?

I just did the 15t and I love it. I'll try it for a few months to see for sure. I think at some point I'll try the 15/45 to see it'll work for me. My rides will be half back roads, and half highway.

[JMcDonald]

I run a 16/41 combo and my daily commute to school is 3 miles with about 10 stops. My daily ride to work from my home is about 5-10 miles depending on which way I take, but still involves probably 10 stops on average. I also do lots of highway riding with friends, and if I am riding aggressively I am usually in 4th or 5th anyways, rather than 6th. It does it all just fine.

Gearing on this bike is really just a completely subjective balance between how much off-the-line pep you want vs how smoothly you want the bike to behave. Calling any combo "perfect" or "better" is not really useful or even based on anything but personal feeling. Some people have tried even slightly taller gearing and gone back to stock in disappointment, while others have gone to the far end of the spectrum and loved it. There is no difference in power output or general acceleration capabilities once up to speed, just a change in how the bike pulls and responds at the lowest speed ranges. With my gearing change of over 25%, the reduction in pep was noticable below about 10mph, but that is over literally about 15 feet after a stopsign, and I have never been one to like launching hard anyways. I don't have any trouble pulling off either, especially after tuning the low-speed ranges of the carb. Typically just briefly slip the clutch at about 2000rpm is all that is needed pull off ahead of traffic, though it will smoothly pull from 1500rpm, or about 5mph.

If you want to do it with numbers, you can examine your riding style to see if you prefer to be in higher gears and how you feel about the shortness of first, and use that to determine if you want to go longer or not.

[wild-bill]

Yes many have gone even taller on the gearing than what I've got. But I won't consider it until some carb work is done. The bike bogs down below 2,000RPM, making it harder to take off. How do you get rid of that problem? Shim needles or do you have to adjust the idle mixture screws?

[JMcDonald]

I have a jet kit and had messed with the needles some, but I want to say, IIRC, I didn't really get the most improvement in low-RPM response (like 1-3k RPM) until I played with the idle mixture screws.

http://www.ninjette.org/forums/showthread.php?t=10246

And yes, the first time I rode my bike with the taller gearing I was a little worried because I honestly didn't like how different it was off the line. I almost fell over once in a tight-radius right turn from a stop because I was expecting more acceleration for the same input as I was used to. However, over a short time I got used to it and began to enjoy it more and more, but it still didn't run all that well below about 15mph or ~4k RPM. However, adjusting the mixture screws and probably the needles as well made a huge difference and, like I said now it will pull smoothly from 1.5-2k. Hell, I sometimes leave it in 2nd gear if I am going through areas with multiple stopsigns, and it still pulls cleanly and smoothly from stops. My 2nd gear is exactly like stock 3rd gear, if that tells you anything. Of course it isn't very aggressive doing this, but it doesn't bog or lug and it keeps me from having to constantly shift up and down when Im hitting a stopsign every 1/8 mile.

[slolane]

Very well put JMcDonald

@ Yasko: I find the 15/42 suits me well on everyday rides, highway and back roads. My goals were to lower the rpm's a bit, make the gears a bit longer and shift less. With the 15/42 fitting with the stock chain testing was easy and not too costly. It really is a personal preference and works well for me.

[JMcDonald]

Yes, I think a lot of people wouldn't like the relative lack of low-speed pep of my bike, but it does not bother me at all for what I gained for myself everywhere else in the speed range. It does not feel any slower when passing traffic or what-not, because in those cases it is just a matter of being in the right gear. In moderate traffic where I might need to quickly pass cars to keep good road positioning, I might just cruise at around 40mph at 8krpm in 2nd gear, which would be exactly like cruising in 3rd gear on a stock bike. If cruising at around 50mph, I will use 3rd at the same 8krpm, whereas I would need to be in 4th on a stock bike. So, in those cases, the amount of pull available is really no different. Or, if I am trying to make my way through holes in slower highway traffic, I might just keep it in 4th gear which is quite close to factory 6th gear, putting me back in the 9k range at 75mph like normal 6th.

Really the main difference is just less shifting. A little more attention needed to be paid to keeping RPMs in a good range, because it basicaly took 6 gears and spread them out into 4, but I got used to it without much fuss. But, for example, while on a stock bike it might be normal to shift into 2nd halfway through an intersection and still have a decent amount of pep to go. Given that my first gear is closer to stock 2nd than stock 1st, and my 2nd gear is identical to stock 3rd (what a mouthfull), if I shift too early I might land at only like 4k in 2nd gear, which makes it more difficult to quickly accelerate should I need to. But, it didn't take long to get used to just making sure I take the engine to at least 8k in 1st before shifting, so that I don't land too low in 2nd. Of course, if I am deliberately riding calmly (like when the engine is cold) or in traffic too heavy to bother cutting into opening, this isn't an issue and I will usually shift lower. But if I am riding more aggressively I will tend to shift out of 1st and 2nd at around 9k revs, which is about 31 and 46mph, respectively.

[Yasko]

Thanks guys.

I LOVE THIS SITE!!!!!!!!

[wild-bill]

Today I went riding. And aimed for top speed. It seems like top speed has been reduced with the gearing change. In 6th, it wouldn't go past 90 indicated. Downshifting to 5th got me up to about 95. With the 14t, I could hit 100 in 6th. I tried this going both east and west, so wind probably wasn't a factor. But it only has 1,400 miles. Maybe the engine isn't broken in fully. On the DR650 I used to have, it would only hit 95 indicated when it had 1,000 miles on it. But after 3,000 miles, 105 was easily attainable.

[JMcDonald]

Thats weird. My gearing changed increased my top speed a couple mph because it lowered the revs down closer to peak power. I was able to hit about 91 or 92 (100 or so indicated) in stock 6th, but was able to hit about 102 or 103 indicated with the gearing change. This was topping the bike out every day on the same stretch of road for several months on my way home from work, so it is the average of dozens of runs.
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[Yasko]

Originally Posted by JMcDonald

This was topping the bike out every day on the same stretch of road for several months on my way home from work,
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[JMcDonald]

Is the chain too tight? That will rob power considerably. I accidentally did that when first installing my sprockets.
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