Sprocket change for lower rpm's at highway speed

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OdinSon

New member
I see just about everyone goes -1+2 for better acceleration but what about for lower rpm cruising? I'm not a hooligan, I don't care about wheelies or other juvenile activities. I think the FZ8 has more than enough power as is but when I'm on the highway for a long time or just on a really long trip sometimes the vibrations and high rpm's can get annoying. Has anyone done a different set up like in the other direction? What were your results like. Once the 3 feet of snow melts I might replace my sprocket and change and the extra info would be nice.

Thanks.
 
Blackfin

Blackfin

New member
Pure Performance Cycles shows a selection of "Supersprox" rear sprockets for a 525-pitch chain for the FZ8:

http://www.pureperformancecycles.co...Supersprox-Stealth-Rear-Sprocket--10--12-FZ8/

They show tooth counts of 41T and 42T, then 47T, 48T and 49T. A stock FZ8 has 46 teeth on the back.

As a sample of what you'd see, consider that at 75MPH in 6th gear, the engine will be turning at roughly 5350RPM.

With a 41T sprocket you'd see 4765 and with 42T you'd be at 4880.

(The front sprocket would give a larger percentage change per tooth count but there's limited room on the front to go to a larger sprocket.)
 
O

OdinSon

New member
I never once said the majority of my riding was highway. The majority of my rides are 6-8 hour long trips that mostly consist of back roads and higher speed route type roads.

As for the comment about choosing to own an fz8 if I did mostly Highway riding... Why would you choose to own an fz8 then if you're goal is wheelies, track days, 100+ mph speeds, racing, or general jackassery? The FZ8 wasn't designed for that stuff. It was designed to be a great do anything middleweight bike, a jack of all trades bike.
 
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Jafran

New member
OdinSon said:
I didn't think a sprocket could look that awesome. I bet that would look so nice on the bike.
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If you do go down some teeth on the rear sprocket, I'd be interested in hearing about how you like it. Most of the time I'm okay with the stock gearing of the FZ8, although I too wish the RPMs were lower at highway speed. I see that some of the newer naked bikes from Yamaha are spreading the gears out a bit, which is a trend that I tend to agree with in these bikes that work so well as all-arounders. According to Motorcycle Consumer News, at 65 mph, the FZ8 is turning 4900 RPM, the FZ-09 is turning 4525, and the FZ-07 is turning 4700 (all 6 speeds).
 
Blackfin

Blackfin

New member
Jafran said:
If you do go down some teeth on the rear sprocket, I'd be interested in hearing about how you like it. Most of the time I'm okay with the stock gearing of the FZ8, although I too wish the RPMs were lower at highway speed. I see that some of the newer naked bikes from Yamaha are spreading the gears out a bit, which is a trend that I tend to agree with in these bikes that work so well as all-arounders. According to Motorcycle Consumer News, at 65 mph, the FZ8 is turning 4900 RPM, the FZ-09 is turning 4525, and the FZ-07 is turning 4700 (all 6 speeds).
Click to expand...

It's always sort of surprised me that bike mfrs don't make at least 6th gear on sport-touring bikes like these an overdrive gear. I love close-ratio transmissions -- especially 1-4 -- but by the time I'm in 6th, I'm most likely cruising leisurely and would gladly trade lower RPM for rear wheel torque. We've got a 1.201:1 ratio for 6th right now and cruise right around 4450 at 60MPH. A 0.97:1 (for example) 6th would get us closer to 3575RPM and would likely give us better fuel economy too.
 
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OdinSon

New member
Yes exactly! If there was an overdrive gear I wouldn't even think of changing the sprockets. When on the highway I'm usually at about 75 mph so stock gearing is 5340 rpm, going to 16 front and 44 rear (+0,+2) would bring that down to 5108 rpm, and going 17 front and 44 rear (+1,-2) would lower the rpms further to 4808. I'm thinking +1-1 might be ideal. I do a lot of cruising around 40 and 75 mph. For comparison going -1+2 at 75 mph is 5944 rpm.

Teeth---Speed---RPM
16-46___40___4153
________75___5340
16-44___40___3972
________75___5108
17-45___40___3824
________75___4917
15-48___40___4622
________75___5944

As for brands I'm looking at Vortex steel for the sprockets and JT gold chain.
 
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OdinSon

New member
You mean the last sentence where I stated exactly what I thought it was for? "It was designed to be a great do anything middleweight bike, a jack of all trades bike." I wouldn't say that the FZ8 was designed for stunting or racing. There are other bikes in Yamaha's lineup better suited to the purpose. With its mostly upright riding position, detuned engine for lower and middle end performance it seems pretty obvious what the bike was designed for. When I got the FZ8 it was for the styling and the type of riding I do which it does great at.

Why do you bother posting in this thread if you're not going to add anything to the relevant discussion?
 
9 Lives

9 Lives

New member
I changed my front sprocket to 17 teeth.

The chain still fits no problem.

I found it drops the RPM just enough, I wouldn't want to go any lower.

I am at about 4800 RPM at 110 kph (68 mph)

This also fixed by speedo error, right on the money now.
 
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OdinSon

New member
Oh thanks! I was really wondering if a 17t sprocket would fit. Thats good to hear about it fixing the speedo, the speedo being off has always annoyed me.
 
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bimmertech12

New member
OdinSon said:
. Why would you choose to own an fz8 then if you're goal is wheelies, track days, 100+ mph speeds, racing, jackassery? The FZ8 wasn't designed for that stuff. It was designed to be a great do anything middleweight bike, a jack of all trades bike.
Click to expand...

Have you ever seen the official press release ad for the fz8? Lots of stunt riding, nose wheelies, stoppies, burnouts, etc...and as for track days,i routinely went to blackhawk for open track days and beat on quite a few r6s.
 
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OdinSon

New member
Gee, thanks for adding your valuable and relevant input to this thread. Instead of talking about some marketing pictures you saw once lets look at an excerpt from Yamaha's official press release:
Looking for the motorcycle that does it all with style and performance? Look no further than the 2011 Yamaha FZ8. The FZ8 fills the gap for sport riders who feel a 600cc is too small and a 1000cc is too big. The muscular, naked bike styling gives it an aggressive, mass-forward stance while the comfortable, upright riding position with a compact design contributes to the bike’s first-rate handling. This bike simply excels both in the morning commute and on that spirited weekend ride on a twisty back country road.
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This bike simply excels both in the morning commute and on that spirited weekend ride on a twisty back country road

And this is from Yamaha's website today:
The 779cc engine combines top end components, including ceramic-composite-coated cylinders and forged aluminum pistons, with a carefully optimized crankshaft to deliver the perfect power curve and torquey performance character for this category.
The FZ8 fills the gap for sport riders who feel a 600cc is too small and a 1000cc is too big.
Muscular, naked bike styling gives an aggressive, mass-forward stance. This bike screams attitude.
Comfortable, upright riding position with a compact design that contributes to the bike’s first-rate handling. This bike simply excels, both in the morning commute and on that spirited weekend ride on a twisty back country road.
Cast aluminum frame and Controlled-Fill aluminum die-cast swingarm is lightweight and provides the ideal rigidity balance for outstanding cornering performance.
Click to expand...

Before I bought the FZ8 I read every review I could possibly find about the bike. Many- if not all the reviews echo what Yamaha has to say about the bike and what it was designed to do. Much of the riding I do is exactly what this bike was designed for according to Yamaha and almost all reviewers out there.
 
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bimmertech12

New member
Congratulations. You dont push your bike to the limits. You must be sooooo perfect. I have 2 friends with fz8s that routinely track them. And it wasnt pictures at all either, it was the commercial for the bike. Now if you've done so much research on the bike, im sure you can keep on researching what different sprocket teeth count will do for you highway riding instead of getting on here and sticking your nose in the air
 
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OdinSon

New member
Er okay, still marketing materials. We all know how reliable and trustworthy marketing materials are. The point of this thread was quite simply to get other peoples perspective and see if anyone else has done it. I'm not sticking my nose in the air at anyone. You and one other person decided to comment in this thread without adding anything at all to the discussion. The other person either removed their comments or had them removed.

I ride my bike hard but no I'm not stupid or careless enough to push it to the limits. I have a beautiful fiancee, a promising career, and great family and friends. Pushing it to the limit and showing off doesn't mean anything for me. I would rather decrease my chances of not ruining my bike, injuring myself (maybe permanently), or possibly not coming home at all. It's good to have your priorities figured out.
 
9 Lives

9 Lives

New member
That video is real funny, they only show the fz8 doing a burnout. All the other stunts were done on another bike. Just marketing hype since the stock FZ8 doesn't have the power to do a power wheelie, nor the front braking power to do a stopie.
 
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OdinSon

New member
There is some stunting with the 8 later in the video. The R6 (I think) earlier in the video definitely looks more controlled while stunting. My favorite part is towards the end of the video about 2:11 the rider is taking off from his group of friends, showing off and acting cool. I got a bit of a laugh at that.
 
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