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Discussion Starter · #1 ·
I have read and discussed a lot and wanted to reach out to guys here concerning this before I make my decision and order parts. Goal is I want my bike to do 200-210 w/ GPS speedo. So I need some gearing changes. I know I will lose acceleration and that unavoidable, but I don’t want to go overboard with taller gearing. Im hoping there is a good middle ground, to be able to hit my mph goals, while with the power of this bike not losing to much acceleration off the line. I wish there was some real world results and data. Like if I take just one tooth down in the back 17/44(45 OEM?) how much will I get out of that. Or 16/43?
any thoughts?
 

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You can do the math with the following information

1. Maximum RPM
2. Final transmission ratio at the output shaft (in the service manual)
3. Final drive ratio (sprockets)
4. Circumference of the tire with some factor for tire growth at speed.

I'm not sure of the 1k bikes but 600s and 750s run out of horsepower long before they run out of RPM.
 

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Will your bike hit the rev limiter in 6th gear?
If not I think you would have to go with something like a power commander that tricks the bike into thinking it's in 5th gear.
Like John suggested I think it would take a very stout 1000 to do an honest 200.
 

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Go to gearingcommander.com. You can input your specific bike and it will calculate all the speeds in all the gears given different gear ratios.
 
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Discussion Starter · #6 ·
Check this out. I was talking with someone who said with a flash and -3 on the rear, keeping the front sprocket the same (17) should put me all over 200+
In looking at this chart. It doesn’t change a thing?
also take note in the top chart for “stock” 6th gear at 13,200 it shows 178mph. But in the Custom chart below. If you look at the box highlighted in red this is the STOCK mph rating of tooth count. It’s showing 167.3.
something is not right.
296084
 

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The red box is the stock gearing. That chart shows all the various combinations for you. The top row is -3 rear and last column +3 front for 210.
 

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What I see in the first chart is that in 6th gear, 10x the rpm gives you 10x the speed. The tire circumference is a lot different at 17.9 mph vs 179 mph.
 

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Discussion Starter · #9 ·
The red box is the stock gearing. That chart shows all the various combinations for you. The top row is -3 rear and last column +3 front for 210.
Yes. I understand that. But the top graph show what the bike is with stock gear box. So if you look at 6th gear at Top RPM. It shows 178.
So then on the bottom graph where you can see the differences of gear/tooth changes. The one box in the middle showing +\~ 0 for both. Meaning Stock, for top MPH on top gear/with top RPM it should show the same MPH. 178. It doesn’t. It shows 167
 

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Yes. I understand that. But the top graph show what the bike is with stock gear box. So if you look at 6th gear at Top RPM. It shows 178.
So then on the bottom graph where you can see the differences of gear/tooth changes. The one box in the middle showing +\~ 0 for both. Meaning Stock, for top MPH on top gear/with top RPM it should show the same MPH. 178. It doesn’t. It shows 167
No. The top chart is showing the custom (-3 rear) data not stock. If it was showing the current stock data the word "Current" above the chart would be in green. If you look at the bottom chart, the top row is for the -3 rear you specified. The column with the red square shows results for a stock front sprocket as 178.5 which matches the upper chart.

Go back and click the word "Current" and it will sort itself out. They use the term current because many already have gearing changes installed and don't need stock information.
 

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If your bike will run an honest 186 now and you want it to run 200 you need to gear it up by 7%.
17-45= 2.64x.93=2.46.
18x44=2.44.
You can check my math but I think I got it right.
 

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Winchester has a point. It bears mentioning that this data gives you the surface speed of the tire. Presumably if the rear tire surface is moving at 200mph and in contact with the ground you should be moving at 200mph. However, in real life application there are losses not accounted for such as vehicle drag co-efficient, mechanical drive train losses, surface grade, wheel slippage, etc. 200mph on the chart is not likely to be the actual measurement in real world applications with out mechanical upgrades to overcome those losses.
 

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Thank you so much guys. I will also check out the website. Yes it hits the rev limiter in 6th. View attachment 296083
Not sure exactly where this photo is taken? Where are you finding a safe smooth place to go this fast? LOL.
As in, is this a closed course for you? Any any other vehicles around (like tractors LOL- inside joke)?
Be safe, OK?
 

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Discussion Starter · #14 ·
No. The top chart is showing the custom (-3 rear) data not stock. If it was showing the current stock data the word "Current" above the chart would be in green. If you look at the bottom chart, the top row is for the -3 rear you specified. The column with the red square shows results for a stock front sprocket as 178.5 which matches the upper chart.

Go back and click the word "Current" and it will sort itself out. They use the term current because many already have gearing changes installed and don't need stock information.
Ok. Now I feel stupid. Yes that red box is for 17/48. Stock is 45. I just had it in my head the middle of both where the equal sign was stock. And it was showing +-3 on the graph. Thank you.
 

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Discussion Starter · #15 ·
Not sure exactly where this photo is taken? Where are you finding a safe smooth place to go this fast? LOL.
As in, is this a closed course for you? Any any other vehicles around (like tractors LOL- inside joke)?
Be safe, OK?
Oh yeah, sure…..closed course. If by closed course you mean wide open HOV lanes that are so expensive that not a single car was in the two lanes for miles. Though I we really need but 15-20 seconds to hit 186+, that straight away is a good mile and a half. There are a couple of them around here, but that’s about it.
there seems to be not many sport bike riders around here let alone 1000’s. Northern Virginia/D.C is a war zone if riding a motorcycle.
 

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Discussion Starter · #16 ·
If your bike will run an honest 186 now and you want it to run 200 you need to gear it up by 7%.
17-45= 2.64x.93=2.46.
18x44=2.44.
You can check my math but I think I got it right.
this is good stuff. Exactly what I wanted. But. The speedo is reading 186 and from what I’m told that 5-10 off. So it’s probably 175-180.
I’d rather not change the front sprocket size if I can. Would the same thing be if I did 17/41 since going 1 up on the front is the equal as 3 down in the back.
 

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That would be 2.41 so yes but the speedometer would still be off of course.
To get a true speed you will have to correct the speedometer or use a GPS system.
 

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Discussion Starter · #18 ·
That would be 2.41 so yes but the speedometer would still be off of course.
To get a true speed you will have to correct the speedometer or use a GPS system.
I already have a Garmin 72H ordered.
I want to get a sprocket set for 200+ runs but not extreme so will prolly go with the 17/41. And then also a set for the most common mod for increased acceleration to have on the bike for the majority of the time.
will probably send my ecu to Chris Moore to have him flash it to release all the limits and for the 200+ sprockets. But I will need to learn to do this myself so it can be changed. Unless, would the mapping/tune need tobe changed when I go opposite direction of 17/41. I’m assuming it does. But maybe it doesn’t.
 

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You're around D/C area? LOL- figures.
 
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