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[jagerbomb]

I traded in a 2009 SG on my 2011 SESG. I immediately noticed that the gearing feels higher. My best bud has a 2009 SG and last weekend we were comparing tach readings at 80mph. I had 2900 showing he was around 3100. I pulled out my books and they appear to show both bikes have the same gearing in the trans, the primaries, and the final drive. Whats your observation? I'm contemplating during the 30 tooth final drive output gear and the belt.

Update: I was at bike week in Daytona and managed to rack up 1400 miles during the week. Got along side my buddy again and now they are identical on RPM. We could only figure maybe he was in 5th gear last time? With all the research I did it didn't make sense that it should be different. Overall super happy with the way she performs

Mark

[ultrafxr]

I can only compare my '11 to my '07 and the '07 is way, way tall.  For me the '11 is just right.   

[grc]

Assuming both bikes are stock, the primary and trans ratio's are definitely the same.  As far as I know, the final drive ratio's (trans to rear wheel) are also the same, but that's an easy one to verify, just count the "teeth" on the rear sprocket.  The other part of the equation that hasn't been mentioned is the tire.  Are both bikes running the same outer diameter tire size?  You can't go by the tire size designation, you'll need to check the O.D. specification for each tire or actually measure them.

If all of the above are equal, then I'd say the tach's or speedo's are off.  Easy enough to calculate speed versus rpm once you have the tire O.D. and overall gear ratio information.


Jerry

[Fullsac Performance]

I traded in a 2009 SG on my 2011 SESG. I immediately noticed that the gearing feels higher. My best bud has a 2009 SG and last weekend we were comparing tach readings at 80mph. I had 2900 showing he was around 3100. I pulled out my books and they appear to show both bikes have the same gearing in the trans, the primaries, and the final drive. Whats your observation? I'm contemplating during the 30 tooth final drive output gear and the belt.

The gearing is the same from 09-2011. 2.87 final drive. The 30T will drop it to 3.06. The gearing chart says 2994 RPM at 75 mph with the 3.06
Stock speedos are 6% fast with a new tire. I see this everyday on the dyno. As the tire wears they get even faster. I run the 3.06 on my 107.
I very cautiously went to the 31 and then the 30T. Amazing improvement everywhere. Another benefit for me, quieter exhaust at 75-80.
The motor is laboring as much and makes less noise with less throttle required to maintain speed. The girlfriend thought I was testing new mufflers
and commented on how quiet they were. Less vibration too. Its truly one of those overlooked and underated mods. Stock 6 speed are over geared.

Steve George
Fullsac Performance

[kraut]

@Steve:

please explain further.

[dayne66]

The gearing is the same from 09-2011. 2.87 final drive. The 30T will drop it to 3.06. The gearing chart says 2994 RPM at 75 mph with the 3.06
Stock speedos are 6% fast with a new tire. I see this everyday on the dyno. As the tire wears they get even faster. I run the 3.06 on my 107.
I very cautiously went to the 31 and then the 30T. Amazing improvement everywhere. Another benefit for me, quieter exhaust at 75-80.
The motor is laboring as much and makes less noise with less throttle required to maintain speed. The girlfriend thought I was testing new mufflers
and commented on how quiet they were. Less vibration too. Its truly one of those overlooked and underated mods. Stock 6 speed are over geared.

Steve George
Fullsac Performance

So....does the 30 tooth also bring the speedo more in line with actual speed as well?

[Fullsac Performance]

So....does the 30 tooth also bring the speedo more in line with actual speed as well?

Lower gears make it read even faster. Easily corrected with TTS.

SG

[Skippy620]

Everything sounds very positive to change the gearing for performance. But, my question is how does dropping to a 30t or a 31t effect gas mileage ?  Anyone have any real life gas mileage figures ?  I ride with a group that loves to pound out the miles and would appreciate the extra performance punch, but dropping in gas mileage is a concern.  Thanks   

[mike70]

dropping from 31T to 30T lowers RPMs??? lower RPMs?? less fuel?? or vise versa.

[jagerbomb]

It raises the rpm by going to 30T

[Skippy620]

I understand that dropping from a 32t (stock front pully) to a 31t or 30t raises RPM.
What I'm interested in how does this change effect highway gas mileage since your reving the motor more. 
I'm interested in making the change for added performance, but I'm hoping the change doesnt' mean a significant drop in fuel mileage.
Thanks

[Fullsac Performance]

I understand that dropping from a 32t (stock front pully) to a 31t or 30t raises RPM.
What I'm interested in how does this change effect highway gas mileage since your reving the motor more. 
I'm interested in making the change for added performance, but I'm hoping the change doesnt' mean a significant drop in fuel mileage.
Thanks

Most situations your milage will improve or stay the same. Bogging the engine sucks gas. Twisting the throttle open at 70 mph/2600 rpm to
pull a hill will raise the MAP past 80 KPA pretty easy and into open loop where they run considerably richer to support the load.
The lower 3.06 gear will see 3000 RPM at 75 MPH GPS. These engine make peak TQ right in the 3000-3400 range. If your running heavy,
that's right were you need to be to pull hills and push head winds.

Steve George
Fullsac Performance

[cyril]

So would i be correct to think the 30T will reduce top speed ?
What about 0-60 ?

Just a question not bothered about top anyway doubt i will ever try to find it but interested to the effect it would have.
I agree 6th is like overdrive. IMO

[Fullsac Performance]

So would i be correct to think the 30T will reduce top speed ?
What about 0-60 ?

Just a question not bothered about top anyway doubt i will ever try to find it but interested to the effect it would have.
I agree 6th is like overdrive. IMO

Stock bikes are so over geared they go fastest in 4th gear. The 3.06 might allow 5th to become the fastest.
6th gear? No way. So to really answer your question, no they do not loose top speed, they gain it.

SG

[Proctor]

What about a built engine.  I have the tq to run in 6th, but I have been wondering if I should drop a tooth on my SESG with my build.
I have always dropped a tooth in front on my sport bikes just for the performance aspect. Can you adjust the speedo with the SERT or do you need a speedo healer?