Gearing questions.

alhope34

alhope34

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Yes I did a search and couldn't find anything that answered all my questions to my satisfaction.

After a long highway trip I have in June, (about 8000 kms in 3 weeks) I'm considering changing up the gearing on my bike. Right now it's obviously stock. I'm thinking of going +5 rear for a couple reasons. First is that I've read going -1 on the front MAY wear the chain out faster, which I don't want. I do a lot of km per year so I want it to last as long as possible. Secondly, I like the look of a larger rear sprocket anyway. Are there chains out there that come with 5 extra links that I would require, or do I need to buy two chains and splice them together? I know I will need a speedo healer. When I set the healer, will it throw my odo out of whack or will it set it properly? I have no idea if the odo reading is linked with the speedo and if the speedo healer will put the odo reading back to actual kms ridden as well as set the speedo right.
 
alhope34 said:
Yes I did a search and couldn't find anything that answered all my questions to my satisfaction.

After a long highway trip I have in June, (about 8000 kms in 3 weeks) I'm considering changing up the gearing on my bike. Right now it's obviously stock. I'm thinking of going +5 rear for a couple reasons. First is that I've read going -1 on the front MAY wear the chain out faster, which I don't want. I do a lot of km per year so I want it to last as long as possible. Secondly, I like the look of a larger rear sprocket anyway. Are there chains out there that come with 5 extra links that I would require, or do I need to buy two chains and splice them together? I know I will need a speedo healer. When I set the healer, will it throw my odo out of whack or will it set it properly? I have no idea if the odo reading is linked with the speedo and if the speedo healer will put the odo reading back to actual kms ridden as well as set the speedo right.
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+5 in the rear will result in higher revs at a given speed, compared to stock. Is that what you want, or do you want a gearing change to give lower revs at highway speeds?
 
The odometer and speedometer are linked, they both operate from the same input signal. Changing one will change the other by precisely the same factor.

As far as the chain goes, normal practice is to buy a chain longer than you actually need and then take links out of it as needed when you install it.
 
I want the higher revs for acceleration and to make wheelies easier, to be honest. it sits at about 7.5k rpm on the highway at 120 km/h (128 on the speedo) and I'd be happy with ~9k rpm at that speed. I don't imagine 0/+5 would go much beyond that.
 
Brian, do you have any knowledge about my bikes chain? Any idea how many links I need with OEM gearing? I guess I could go count them but it's late and 13 floors underneath me and I have to be at work by 6 am tomorrow lol.
 
nevermind, guess I should have looked better on google. 16 front and 43 rear are OEM. So I'd be going to 48 rear. 112 links is OEM chain size, and most 520 chains come with 120 links. I'm guessing that would still be enough.
 
7500 rpm at 120 km/h in 6th gear the way you have it now? That doesn't sound right. That's about how my 400 is geared. You should be near 6500 rpm in 6th at 120 km/h. If you are putting on high annual mileage, high revs at highway cruise gets old fast ...

Rough rule of thumb is that about half the teeth on the sprocket will be engaged in the chain, so if you go up 5 teeth you will need about 2.5 :-) more links in the chain. Obviously that's not possible, the chain can only be changed by an even number of links. A chain with 2 more links will work with the axle a bit further forward, 4 more links will put the axle a bit further back, this is why you buy it longer than you need and set it where you want it when installing it. I have no idea how many links your stock chain has.
 
Ok thanks for the info. And yes, 7400-7500 rpm at 120 km/h REAL speed using my gps is correct. The speedo does read 127-128, though. Maybe it's because It revs high even comparing to other 600's of the same year? 16.5k redline.

Also, it seems like a 46t rear is the largest I can find from a number of online sites to order from. Odd. I thought there'd be more selection.
 
Also, will going to a 15t front dramatically reduce my chain life?
 
No. My 250 came stock 15-43. Many change it to 16-43 some to 16-41. All with the same 108 link DID520V chain.
 
alhope34 said:
I want the higher revs for acceleration and to make wheelies easier, to be honest. it sits at about 7.5k rpm on the highway at 120 km/h (128 on the speedo) and I'd be happy with ~9k rpm at that speed. I don't imagine 0/+5 would go much beyond that.
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http://www.gearingcommander.com/

Just FYI, a -0/+5 is the same final gearing as a -1/+2.

Did you buy your bike brand new? Those GPS speed/RPM numbers don't sound right, maybe the previous owner put on a -1 front already? Count the teeth and check ;)

With stock gearing your bike should be revving 6710RPM at 120kph and with a -0/+5 you would be revving 7490RPM. Your theoretical top speed will drop from 272.7kph to 244.3kph.

alhope34 said:
Maybe it's because It revs high even comparing to other 600's of the same year? 16.5k redline.
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HAHAHA where did you read it's got a 16.5k RPM redline!??!! LOL! Try 15250RPM, 750RPM less than most other 600's of the same year. And that's got nothing to do with why your speedo is off from the factory.

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alhope34 said:
Also, it seems like a 46t rear is the largest I can find from a number of online sites to order from. Odd. I thought there'd be more selection.
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Because people drop one tooth in the front. These guys have up to a +4 rear available: http://www.superbikesupply.com/mm5/...awasaki&Category_Code=520-conversion-kawasaki


If you REALLY want your bike to wheelie easier call or text Bill 289-929-5477, he'll remove all the restrictions in your ECU.
 
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Thanks but I know what my redline is at, I could post a picture of my tach when I get home. Also, I did buy the bike new and I'm 100% positive on the actual speed vs rpm. Once again, at 7400-7500 rpm the gauge reads 127-128 kmh when the actual speed is 120 kmh as given by my gps. I am absolutely positive of this.

I really doubt every single thing is out of whack with my gauges and I doubt even other zx6rs from my gen ive seen showing red starting at 16.5k would be wrong.
 
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I've read most bikes intentionally have the speedometer higher than actual. Ways to work around it include a larger front tire.
 
Technically, that's correct on some bikes. But not so much lately unless it's retro.
 
alhope34 said:
Thanks but I know what my redline is at, I could post a picture of my tach when I get home. Also, I did buy the bike new and I'm 100% positive on the actual speed vs rpm. Once again, at 7400-7500 rpm the gauge reads 127-128 kmh when the actual speed is 120 kmh as given by my gps. I am absolutely positive of this.

I really doubt every single thing is out of whack with my gauges and I doubt even other zx6rs from my gen ive seen showing red starting at 16.5k would be wrong.
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Your redline/rev limiter is 15250, just trust me on this. Whatever you think it is, try and get there, and you won't. It makes no difference at all where the red bits start on the RPM gauge, the printing or the colours of the lines have no effect on when the rev limiter kicks in.

Find me a dyno run without a flashed/hacked ECU that goes over 15250rpm... nope, you won't: https://www.google.ca/search?q=2012+zx6r+dyno&source=lnms&tbm=isch

Good news about owning the bike since new, kinda strange your speed/RPM numbers then though.
 
That's odd to me they'd put the red on the gauge higher than it will actually go. Is the gauge just for show then? Lol. Im not trying to be a dick im just trying to understand why the heck they'd do that.

Also, just how much would my oem ecu be limiting power in the first couple gears? I never imagined any 600 would be limited in any way seeing how there are countless other ss bikes that make more power. Thanks for all your info. Maybe the tach reading hjgher than it can actually go might be why its showing that high of an rpm in 6th at highway speed?
 
alhope34 said:
That's odd to me they'd put the red on the gauge higher than it will actually go. Is the gauge just for show then? Lol. Im not trying to be a dick im just trying to understand why the heck they'd do that.
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Don't underestimate what an OEM will do to gain a perceived advantage. Yamaha has calibrated the tach to be out of sync with actual rpm to make it appear higher revving. How they expected to get away with that is still an unknown in these quarters. It was the R6 few years back.
 
Is that why the 02-04 r6 models or whatever it was had a redline on the tach of something crazy like 18k rpm?
 
alhope34 said:
That's odd to me they'd put the red on the gauge higher than it will actually go. Is the gauge just for show then? Lol. Im not trying to be a dick im just trying to understand why the heck they'd do that.
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Not ONLY do they just print up whatever they want for the red line on the face of the RPM gauge, having no relation in real life to the actual rev limiter, but sometimes they even COOK THE RPM GAUGE TO LIE and show more RPM's than you're actually turning! That's why dyno runs are great, you get true RPM without relying on the printing on the RPM gauge or the accuracy of the stock gauge.

My friend bought an R6 that was advertised to have a 17,500rpm redline, and when Yamaha failed to deliver on this promise they just offset the RPM gauge by 1500RPM! INSANE! They gave my friend a full refund: https://web.archive.org/web/20060207021828/http://www.motorcycledaily.com/01february06_redline.htm

alhope34 said:
Also, just how much would my oem ecu be limiting power in the first couple gears? I never imagined any 600 would be limited in any way seeing how there are countless other ss bikes that make more power.
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It's limited HUGE, in the first couple gears plus 6th gear too. If you text my friend he can provide you the actual restrictions. I don't work with Kawi so don't have the specific numbers.

alhope34 said:
Maybe the tach reading hjgher than it can actually go might be why its showing that high of an rpm in 6th at highway speed?
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After how much bad press Yamaha got when they made the RPM gauges lie I couldn't imagine any post 2006 bike doing the same, especially not by over 1000rpm! If your needle does go to 16.5k then you know for sure your gauge is inaccurate. Don't test the rev limiter without load on the engine (i.e. don't test it in neutral or with the clutch in or on the rear stand).
 
Yea, it goes right to 16.5 hitting the limiter. Does your friend tune the stock ecu or just take restrictions off? This seems like a much better route for me to go. I can wring the throttle in first in a straight line like a 250 and the front wheel wont lift unless I hit a pretty big dip in the road.
 
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