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Heey Guys!! Here-we-go With The Gearing Questions Again. I Have A 04' Rkc 113" Pushing 121/123, 3.15 Gearing, 5 Gears And Belt. I Do City Driving As Well As Fun On The Highway. Is It Possible To Get 3.25 Gearing For My Scoot? And Would This Give Me The Best Of Both Worlds As Far As Not Being Too High At 75-80 But Still Giving Me That Bottom End Grunt? What Would This Do For Me? And Would 3.37 Be Better? All Thoughts Are Welcome. Help My Decision Because I Want To Do This Soon!!!! Thanks Guys!!!

Also, Im Just Getting Used To My Newly Built 113" And Cant Imagine Even More Are Snatching Torque!!
Thanks!!!!!!!!!
 

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0043--Licensed to Doof!
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with 123 tq, you want MORE?
 

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Discussion Starter #3
Wellll,............yeeeeessssss!! I Guess Im Curious Because I Here So Much About The 3.37 And How Everyone Goes Bonkers Over The Change. Especially Since Its Not Expensive And Its Not Hurting Anything, And The Results Are Dramatic.
 

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With that much motor and a healthy wide torque curve I don't know why you would change. It will be more fun if it's a bar hopper but on the road the current gearing would help keep the R's down a bit and improve mileage.
 

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here's a rule of thumb.... when you have displacement and torque, make it pull a taller gear instead of wasting the power out the exhaust pipe.

With smaller motors, you need to gear them down to help them pull but once you get adequate torque and size, make it pull gear... wrinkle pavement! ;)
 

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Discussion Starter #6
Hey Tote, When You Say The Rule Of Thumb Is To Pull A Taller Gear, Im Kinda Confused. Does Gearing Down Mean Going Up With The Numbers, Like To 3.27, 3.37. So Are You In Favor Of The Change?
 

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Totenkopf said:
here's a rule of thumb.... when you have displacement and torque, make it pull a taller gear instead of wasting the power out the exhaust pipe.

With smaller motors, you need to gear them down to help them pull but once you get adequate torque and size, make it pull gear... wrinkle pavement! ;)
Little more Dry Humor Tote.

I guess I'm the exception to your rule. The Good Old Boys that helped me when I went to 124 CI recommended just the oppsite of staying with 3.15 overall final drive for two reasons, stroker motors tend to rev slower and due to cam designed to bleed off compression so you can turm them over moves the power band to the right.

They said make mechanical advantage work for you in the RPM you ride most on the street. I followed their advice and have no regrets with doing this. I run 3.37 final drive in 5th and 2.93 in 6th. In fact I don't even have to use one of those +/- 4 degree keys to try and move my power band 400 rpm to the left..>:nope: I did that with gearing and exhaust tuning. I'm not even afraid to downshift to get the engine to rev even faster either.

HDWrench posted one time that my engine reved in 5th as fast or faster than what he was seeing in 4th on his non are shorter stroked builds. I've just barely got 1 HP per CI and no head porting and a CV carb.:wacko:​
 

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Yes, you can get 3.25 gearing with the Andrews set up. I run about 127 lbs. TQ and I LOVE having the 3.25. Nice change over the 3.15 and can still barrel down the freeway in 5th right in the middle of the cam bite. I do mostly high speed highway cruising so the 3.37 is a bit much for me.
 

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Discussion Starter #9
Grock, So Andrews Has A Setup Just For The 3.25 Gearing? If So I May Have To Check That Out. Do You Know Where You Are At About 70mph? Thanks For The Input.
 

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Sorry for jumping in on this but: I have an 07,103bb and i have put the 30 tooth sprocket in, so im at 3.16. I would still like to go to 3.25 or maybe even get to the 3.37 area. Is there anything I can use on the 07 yet that can get me there?
 

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We are mixing years in this discussion.
On the 07, CruiseDrive 6 speed:
You can go from 3:16 to 3:25 by changing the front pulley to a 31 offered by Andrews and Baker. You will need a 2 1/4" transmission pulley tool to get this job done. Do your research on the belt. For the FL models the HDI belt is 1 tooth shorter than stock USA release. On the softail???
You will need to reprogram the speedo for accuracy, easily done if you use a DTT or Tmax, other wise an add-on device may be needed.
How do you know the ratio is 3:16 with the sprocket change? I know the baggers are 3:16 after that change but they start at 2:79. So the change yields a 12% change. I don't know what the 07 softail starts out at but I would guess at 3:00 so the change would then yield 3:36 right? In other words you may be there now. ???
 

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everthing ive read sais the 07's are all 2.79 exept the dyna i think. We have had several discussions about the 30 tooth sprocket on this forum and every discussion everyone who talked about the ratio of the 07s said it was 2.79. I have a great worksheet/chart that someone posted on one of the threads and it shows all this stuff and puts the bike at 2.79. I would post it if i new how ,i just cant figure it out. Im not sure if the 6th gear ratio is the final ratio but my owners manual has the 6th gear as 2.79
 

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If you look at the Andrews website they lay out the ratios up or down from stock and the difference in belt length per tooth +/-.
 

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Do the math, first !!
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66 tooth to 70 tooth

does any one know for sure if a 70 tooth final drive from an 06 dyna,(6 speed) will fit on and line up properly on an 07 ultra, replacing the 66 tooth to put a bit of gear back in the bike ??? i am looking for small gain, about 200 rpm. they should have left the gearing alone for touring like on 06 dyna. JMHO
 
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