Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[FXR2evo99]

Hello Everyone.....

Well after some real deliberations....and after doing an engine modification in FEB of 2011.  I rode my bike last summer and still was a bit underwhelmed by my results....

Just so you know my dyno numbers are 84 HP and 94 Torque.  I modified heads, i.e.: head work, put in a EVL 3000 (V-Thunder Cam), am running a .040 Head Gasket and basically running 9.02:1 CORRECTED COMPRESSION.  I can spend more time talking about the build but the scope of this THREAD is about coordinating gearing and engine modifications while creating the type of riding we desire.

So I have spent last fall really studying the effects of gearing.....so here is what I am in the process of doing:

First of all our OEM set up for all CVO FXR's is the following:

Primary Side:  25T Compensating Sprocket  X  36T Clutch Shell Basket
Secondary Side:  32T Transmission Pulley/Sprocket X 65T Rear Wheel Sprocket  +  133T OEM Kevlar Belt

HERE ARE THE PARTS:

3.36 FINAL GEARING INSTALL & SHIFTER SHAFT SEAL REPAIR:

Part #             ITEM                                                  QTY    EACH    PRICE     20% OFF
SKF 4260       Double Lip Seal  Shifter Shaft Seal      
472810          Federal Mogul Double Lip Seal                   1        6.65                 6.65
12066A          Jack Shaft Lip Seal                                  1                               5.88
12052A          Inner Primary Main Shaft Seal                   1                               3.72
11147            Housing Cover O-Ring (8”)                        1                               1.56
34901-94C     Outer Primary Cover Gasket                       1                             24.32
94137-09       Mainshaft Sprocket SOCKET 1 7/8”              1                149.95   119.96
40001-85       OEM HD 136T Secondary Belt 1 1/2" WIDE    1                200.00    165.60
40217-79A     70T Rear Wheel Sprocket                           1                210.00    119.74
290304          Andrews 5 Speed 30T Trans Pulley              1                135.00      89.00  
H30-06          Rev Tech Primary Fluid                             1                                 6.36
                                                                                                              ---------
                                                                                                              $542.19


Alright first let's go over the price list, you will notice the SKF 4260 and the Federal Mogul Seals listed first, some of you or all of you may know about this repair or not, but if you look at your parts book and locate your shifter shaft and where it comes out of the transmission you will note that there is a seal, which HD sells as a single lip seal which has a propensity to LEAK, as both of my bikes are doing now....lol, so a better SOLUTION is to replace this seal with a completely different seal which is a DOUBLE LIP SEAL and two companies that make the right seal which are both DOUBLE LIP SEALS which HELP to prevent leaking would be either SKF or Federal Mogul (and by the way it's now packaged under TIMKEN because TIMKEN purchased Federal Mogul) so, and by the way the only way to gain access to this LEAKING SEAL is to remove not only the outer primary, as well as the compensating sprocket and the clutch shell basket and the primary chain and tensioner, is that you ALSO have to remove the INNER PRIMARY as well.....oh yeah....it's all fun so to repair this leak it's 4 hours labor at a shop for a $7.00 seal, oh yeah baby, oh yeah.....  



So that's why I am labeling this the Gear Change and Shifter Shaft Seal Repair.  

Ok so let's continue with the parts list descriptors....fortunately I was able to locate a brand new Rear Wheel Sprocket off of ebay for $119.00 shipped to me.  This part can still be purchased from HD but it's retail list is $210.00, ouch.  Next is the Andrews Transmission Sprocket/Pulley which if purchased from Andrews is priced at $135.00 I once again found one on EBAY for $89.00 brand new shipped to my door.  Of course if you do the math for the secondary drive calculations you will note that the 32T OEM Transmission Pulley/Sprocket X 65T OEM Rear Wheel Sprocket calls for a 133T OEM Kevlar Belt.  So if you do the math and reduce the 32T OEM Transmission Pulley/Sprocket down to a 30T Andrews Transmission Pulley/Sprocket and move up the Rear Wheel Sprocket from a 65T OEM to a 70T which is also OEM for different HD bikes you end up needing a kevlar belt which is 32-30 = -2    +    65 + 5 = 70T  so you need -2 +5 = +3T larger belt or a 136T Kevlar Belt.  Upon further research you will discover that all 1989-1994 FXR's use a HD# 40001-85 136T Belt and remember that the 1989 - 1993 FXR's had a final gear ratio of 3.37:1 while the 1994 FXR modeled bikes featured 3.153:1 Final Geared Ratio Bikes.  Use a 136T belt from HD....you don't want to mess around with used belts for this sort of project to say the least. I listed the part number above and the belt is readily available.

[NOTE: Please remember that putting your curser next to the paper clip icon below the photo will allow you to enlarge the photo plus save it to your computer if you desire OR if you merely wish to see it enlarged simply put your curser on the photo and "LEFT" click and it will enlarge]

[FXR2evo99]

You will also note that I listed a tool which is a approximately sized 6" socket which comes with a "donut" that keeps the 6" length socket from hitting the main drive of the transmission which is needed to ACTUALLY remove the 1 7/8" Transmission Pulley/Sprocket NUT.  This tool is required to change out the 32T OEM Transmission Pulley/Sprocket to a 30T Andrews Transmission Pulley/Sprocket.  If you don't wish to do this job yourself in your own garage and you wish to take it to a indy shop or HD, then of course this tool is needless....but you will be paying roughly 5 hours labor to do this job as this job requires you to remove the swing arm as well which is beyond just the scope of removing the inner primary.  The swing arm removal is required anytime you change a belt which isn't that often of course but it's definitely part of this modification since we are lengthening the belt by 3 teeth. You must also remove the tire and replace the rear wheel sprocket from the OEM 65T to a OEM 70T Rear Wheel Sprocket.  I would say conservatively that this is a 5 hour job as far as labor costs are at a professional job, however the professional shop will not clean everything Or put everything back as carefully as I will....so for me this will be probably closer to an 8 hour job.  Cleaning bolts, cleaning the inner primary, cleaning of the threads that will handle the red loc tite at the location of the compensating sprocket, as well as the 1 7/8" Transmission Pulley/Sprocket Nut, and finality the clutch shell basket nut. Not to mention the 2 hour bike cleaning before I even begin this surgery....LOL.  

Ok so let's talk about the FINAL Gearing Ratio Numbers and the combinations you could end up with.

IF YOU DO NOTHING AND KEEP IT OEM:

25T Comp x 36T Clutch Shell Basket X 32T Transmission Pulley/Sprocket x 65T Rear Wheel Sprocket  133T Belt  =OEM 2.925 Final Gear


IF YOU CHOOSE TO MODIFY YOUR FINAL GEARING RATIOS HERE ARE "MOST" OF THE RELEVANT COMBINATIONS YOU COULD END UP WITH:

The Green Denotation Is Indeed The Combination I will be using.

25T Comp x 36T Clutch Shell Basket X 30T Transmission Pulley/Sprocket x 70T Rear Wheel Sprocket 136T Belt = 3.36 Final Gear

25T Comp x 36T Clutch Shell Basket   X   32T Transmission Pulley/Sprocket x 70T Rear Wheel Sprocket  138T*Belt  =    3.15 Final Gear

24T Comp x 37T Clutch Shell Basket   X   32T Transmission Pulley/Sprocket x 65T Rear Wheel Sprocket  133T Belt  =     3.13  Final Gear

24T Comp x 37T Clutch Shell Basket   X   30T Transmission Pulley/Sprocket x 70T Rear Wheel Sprocket  136T Belt  =     3.59 Final Gear

24T Comp x 37T Clutch Shell Basket   X   32T Transmission Pulley/Sprocket x 70T Rear Wheel Sprocket  138T*Belt  =     3.37 Final Gear


* = I know you can purchase a 133T Belt and a 136T Belt from HD, even though the math points to the idea or concept of using a 138T Belt all 1993 and 1994 FXR's use the same belt which is the part number listed above i.e.: HD# 40001-85 which is a 136T Belt so obviously one just needs to set the tension right.  The 1989-1993 FXR's have 3.37 Final Gearing and the 1994 FXR's have 3.15 Final Gearing.

So as you can see there are many options and you can study the merits of any one of them just as you can decide whether doing anything makes no sense at all....lol.....I was just trying to answer the inevitable question but what if you do this combo or that combo....mixing and matching.....this discussion assumes there is merits in my decision to change the gearing or else I wouldn't be doing it.  You may find there are no merits so this thread has little value for you....so the rest of this discussion will be based upon the merits of such a modification.

Given that you see the combos up above, what my research has shown me is that ALL 1989 FXR's through 1993 FXRs actually came with 3.37 final gearing from the factory.  The 1994 FXR's came with 3.15 gearing from the factory.

I am providing 3 gearing charts with certain Final Gearing RPMS for your review, they will be 2.925 Final Gearing, then 3.15 Final Gearing, and then 3.37 Final Gearing.  The difference between 3.36 Final Gearing and 3.37 Final Gearing isn't even worth worrying about....it's so minimal that....it's just a touch shy of 3.37 Final Gearing.  So showing the chart for 3.37 Final Gearing works easily for quick comparisons....it's like 4 or 5 RPM difference not 50 or 100 or 200 only 4-5 RPMS difference.....

What you should be able to do now with the attached charts if you have a dyno of your current bikes performance is to realize, given the cam you have chosen where your particular cam comes on and how via transferring the charting information how your engine modification is actually interacting with the OEM Final Gearing and if you were to modify how it might better interact with such chosen modification.

Regards,

Tim

[FXR2evo99]

Here is the gearing RPM Chart for our OEM 2.925 FINAL GEARING FXR's







[NOTE: Please remember that putting your curser next to the paper clip icon below the photo will allow you to enlarge the photo plus save it to your computer if you desire OR if you merely wish to see it enlarged simply put your curser on the photo and "LEFT" click and it will enlarge]

[FXR2evo99]

Here is the Gearing Chart For 3.15 FINAL GEARING







[NOTE: Please remember that putting your curser next to the paper clip icon below the photo will allow you to enlarge the photo plus save it to your computer if you desire OR if you merely wish to see it enlarged simply put your curser on the photo and "LEFT" click and it will enlarge]

[FXR2evo99]

Here is the Gearing Chart For 3.37 Final Gearing








[NOTE: Please remember that putting your curser next to the paper clip icon below the photo will allow you to enlarge the photo plus save it to your computer if you desire OR if you merely wish to see it enlarged simply put your curser on the photo and "LEFT" click and it will enlarge]

[FXR2evo99]

In a book called:

How To Build A Harley-Davidson Torque Monster
By  Bill Rook 2007

This book has provided some important information over the years from a perspective of modifying one's bike, he actually devoted one chapter, Chapter 5 which is approximately 7 pages long to the merits of gearing.  Some of those thoughts I have recorded here.

Bill Rook talks about a letter he received from Jerry Branch on page 76:

So how important is this gear problem?  Let's see what the legendary Jerry Branch of Branch Flowmetrics has to say about it.  The following is an excerpt from a letter that Jerry sent me back in February of 2000:

Bill,

Harley has the motorcycle (twin cam) greatly over-geared and this is the most important thing that you can do to improve it..  You need to drop the motor sprocket (compensating sprocket) from a 25-tooth to a 24-tooth and change the transmission pulley/sprocket from a 32 tooth to a 30 tooth.  Andrews makes this transmission pulley sprocket and H-D makes the engine sprocket (compensating sprocket).  The motorcycle will run 10 times better everywhere with this setup.  If I had a choice of only one thing I could do to the motorcycle, I would take the gear change 10 to one, even if it were twice the price of the heads, cams, carb, and pipes.  It's a must! Without it, you will only get 5 percent results out of all the other stuff.  Right now it's like having a trailer hooked onto the back of it.  Get rid of the trailer and the motorcycle flies!

Sincerely,

Jerry Branch

Further comments by Rook go on to say:

Jerry clearly makes the point that the stock gearing is not much help in getting the power to the street, and this is an especially strong statement when coming from one of the most famous Harley head porters in the business.  He indirectly says he would choose a gear change over a set of his own Branch heads! Ouch that hurts!

The stock final gear ratio on the TWIN CAM is 3.153:1.  This means that in fifth gear, the motor will turn 3.153 times for each single turn of the back tire.  If you think this is high, check out the gear ratio of an 80-inch Evo Softail.  Would you believe it is 2.925:1 final gearing!  Being geared that high, it's amazing that the Fatboys or the Heritages can get out of their own way.  

It's important to understand that the smaller the gear ratio between the motor and the rear wheel, the harder the engine has to work to turn the wheel at a given rate. If we increase this ratio, the motor will be be able to turn more revolutions to turn the rear wheel at the same rate.  What we are doing through gearing is mechanically increasing the amount of torque we can apply to the rear wheel.  The more torque we apply, the faster we can accelerate.

Stock Twin Cam gearing fifth gear at 2,200 RPMS = 50 miles per hour.  

As with most things in the world of high-performance street harleys, you have to compromise.  If the overall gearing is too high, you won't accelerate worth spit.  If you gear too low, you'll loose top-end miles per hour, and your engine will be racing and turning a lot faster than it needs to at highway speeds.  Of course, the six-speed transmission with overdrive will fix all of this.

Anyway, we're going to have to compromise on a street bike.  Expert drag racers' lives revolve around going fast, and they will often recommend using a final ratio of 3.37:1 for a hot street Harley.  Note that this is for the smaller displacement 80-inch Evo, so it should work well on the new larger Twin Cams.  Again stock on the Evo Sportster's was 2.925:1 and the Twin Cams are 3.153:1, so 3.37:1 is an improvement.

Let's go back up to Jerry Branch's letter above, Jerry's recommendation was to get rid of that "trailer".  If one followed his advice, one would drop the motor sprocket (compensating sprocket OEM 25T) from 25 teeth down to 24 teeth and drop the transmission pulley/sprocket from 32 teeth down to an Andrews 30 teeth.  This is the gear ratio he is recommending, which would be 3.50:1 Final Gearing.  

Jerry Branch is serious.  He is recommending dropping from the stock 3.153:1 (for twin cams) down to 3.50:1.  This should get the RPM up and the back wheel spinning!  

I don't doubt that what Jerry Branch said is gospel.  But remember that in the world of high-performance Harleys, we deal in compromises.

[FXR2evo99]

My thoughts:

After reading all of the above several years ago, it's amazing to me that here we sit in 2012 with Harley-Davidson even making the gearing taller on 2007-2012 bikes going as high as 2.78:1 Final Gearing in the 2007 Touring Bikes.

Notice that there is a reference to the EVO softails as having 2.925:1 Final Gearing as well, which MAY possibly be the basis for why we have such gearing in our CVO FXR 2's, 3's, and 4's, perhaps these combination of parts were the most readily available at the time in 1999-2000 time period.  Remember too that the final gearing for the 1989 - 1993 FXR's were 3.37:1 with the 1994 FXR's being put out of the factory with the 3.15:1 Final Gearing.  One has to wonder whether as time proceeded as to whether the EPA guidelines with emissions and such caused such high gearing as well as a way to compromise meeting the given emissions standard requirements at that time.

All I know for sure is that I too believe as Bill Rook that going to 3.50:1 Final Gearing would be a bit more aggressive than even I would desire to extend myself to.....

I can tell you that 3.37 Final Gearing has been extensively used in the touring bikes as well.....I haven't done the research to be able to quote the actual years but one could do so if so motivated....I do know that the 99-2001 Touring bikes that had the merelii fuel injection were given 3.37:1 final gearing as to be able to have better performance than what the original oem merelli fuel injection was able to provide, because during these same years the 99-2001 touring bikes which left the factory as carbed bikes went out with 3.15:1 Final Gearing allowing both bikes to perform side by side more closely.  The Merelli Fuel Injection just wasn't able to perform well enough as compared to the carbed version bikes so how could the MOCO persuade such consumers at the time to spend another $750.00 for the "upgrade" to FI if one hopped on a carbed bike and felt MORE performance than a FI bike, so they affectively "detuned" mechanically the carbed bikes by putting in taller gearing of 3.15:1 final gearing and sent the Merelli FI touring bikes out with the 3.37 Final gearing creating more punch.....amazing when you study the specifics of what was going on at the time.  Then in 2002 all bikes that were EFI were given the Delphi Fuel Injection and that's when all bikes left the factory, dynas, softails, as well as touring bikes with 3.15:1 Final Gearing.  As they finally had a EFI format that was delivering fuel properly and able to perform capably with the carbed version bikes.

I own a 2002 RKC and it has the delphi EFI in it, it came with 3.15:1 Final Gearing just as stated above and I modified it to the 3.37 Final Gearing back in 2006 and have loved the performance of the final gearing (3.37:1) since I made the effort to change it.  It is wonderful and last summer I spent one day going from Jackson Hole WY back to my home town of Fort Collins, CO traveling through parts of Idaho, and Utah riding on small amounts of interstate highways and mountain roads and plains to the tune of 700 miles in one day, which is the longest I have ever ridden in one day, and was on the bike 14.5 hours and a total of a 16 hour day....going from 45 mph to 85 mph in various parts for various extended periods and I will debate to the end that there is any such extended vibration or discussions worthy that would say the higher RPMS are of any consequence to the enjoyment of riding the bike or the gas mileage for that matter....That bike has been heavily modified and I get around 45 MPH on it.  So reasons of vibrations or fuel mileage or very weak parameters to defeat the merits of such "shorter" gearing.   Once again remember that 3.37:1 Final Gearing came from the factory with all FXR's 1989-1993.  

So I have just collected all of my parts and they are in transit to me at this time, in the next couple of weeks I will have actually performed this modification and provide a report on my findings.....

Given that I have already had my 2002 RKC running for 6 years at the 3.37:1 Final Gearing Ratio, I would say that I will expect no real huge "negative" surprises.

I have also studied where my dyno results with my current build that have come in for my build and can show specifically how going to the final gearing of 3.360:1 will actually allow me to use the power more efficiently as to how my engine has been built.  

I don't think we have spent enough time studying the merits of gearing vs engine modifications that we do.

My hope is that I am creating the "Perfect Storm", and time will tell, the data when comparing RPM charting given the parameters of how I built my engine on paper show that I am.

I simply enjoy a bike that has more torque and given the parameters of where my torque comes on by modifying the gearing to put me in the RPMS where my engine likes running will actually have the opportunity to make the throttle response more congruent with where the engine has been built to run most efficiently.

Regards,

Tim

[FXR2evo99]

Ok for guys NOT running 116 HP or 122 LBS of Torque.....LOL

Here is how a 84 HP and 93 Torque Engine would work given RPM RANGES compared between 2.925:1 FINAL GEARING, 3.15:1 FINAL GEARING and 3.360:1 FINAL GEARING. 

IN 5TH GEAR THE WAY MY ENGINE IS CONSTITUTED I AM GETTING:

90 LBS OF TORQUE 3400 RPMS - 4400 RPMS

Which provides the frame work for trying to put the gearing in a location where I am experiencing my "PEAK" Torque Numbers So let's look a how different gearing will adjust how this looks, in 5th gear:

5TH GEAR:
WITH A 25.5512" (649MM) AVON REAR TIRE

2.925:1 FINAL                         3.15:1 FINAL         3.360:1 FINAL

55 MPH                                  2279 RMPS            2431 RMPS
60 MPH       2309 RPMS            2486 RPMS            2652 RMPS
65 MPH       2501 RPMS            2694 RPMS            2873 RPMS
70 MPH       2694 RPMS            2901 RPMS            3094 RPMS
75 MPH       2886 RPMS            3198 RPMS            3315 RPMS
80 MPH       3078 RPMS            3315 RPMS            3536 RPMS
85 MPH       3271 RPMS            3522 RPMS            3757 RPMS
90 MPH       3463 RPMS            3730 RPMS            3978 RPMS
95 MPH       3656 RPMS            3937 RPMS            4199 RPMS
100 MPH     3848 RPMS            4144 RPMS            4420 RPMS
105 MPH     4040 RPMS            4351 RPMS            4641 RPMS
110 MPH     4233 RPMS            4558 RPMS            4862 RPMS
115 MPH     4425 RPMS            4766 RPMS            5083 RPMS
120 MPH     4618 RPMS            4973 RPMS            5304 RPMS

Now look at this closely when compared to how my engine has been built....this is why when looking at Itank's previous comment about running his FXR4 prior to his engine modification in 5th gear at say 55 MPH was "chugging" the engine, heck you are only turning 2500 RPMS at 65 MPH.  The design of the cam I have installed is showing that my cam's sweet spot in 5th gear where I am getting 93 LBS of Torque is between 3500 RPMS - 4000 RPMS if you study the 2.925:1 FINAL GEARING RPM CHART this means I would have to be going 90 MPH - 105 MPH to take advantage of being in the sweet spot with the OEM GEARING, which means to me that I would be always be chasing that feeling of power in the bike, that ahh hahh moment where the reversion of the cam leaves and the wick of the throttle begins....I would really only feel the bikes real power when passing a car or racing from 90 MPH - 105 MPH.  NOW take a peek at what changing the gearing would do to 3.360:1 FINAL GEARING, the peak numbers of 93 LBS of torque would start sooner because I would be turning more RPMS from 80 MPH to 90 MPH, it's a smaller window but it's an earlier window....meaning that I would see it be available to me 10 MPH sooner than the OEM gearing.

Now let's look at the wider range of TORQUE Numbers, if you look above the way my bike's engine has been modified I am experiencing only a 3 LBS of Torque Difference from the peak number of 93 LBS OF TORQUE but the range of 90 LBS of Torque goes for a greater distance, so let's look at this range now, thus I am experiencing 90 LBS of Torque from 3200 RPMS - 4600 RPMS so let's see how our gearing matches up with this. 

Before we do, I will say that while our bikes typically hit our peak HP numbers much later sometimes around 5250 generally, if you ask most riders where they feel the greatest power it will typically correlate to where their PEAK Torque Numbers appear to show on a dyno chart, that's because this is the location where when you wick the throttle you feel that instantaneous response, so that's why I spend so much time talking about where the peak torque numbers reside instead of where our maximum horsepower resides.....I have tested this theory enough with guys that have dynoed their bikes and then I ask them to go out ride the bike and tell me where they feel the most power or the smile factor in the seat of the pants paying attention to their RPM ranges and typically when we go back and review their dyno charts there is a correlation to their peek torque numbers being within the range to the smile factor....

90 LBS of Torque from 3200 RPMS - 4600 RPMS the way my bike is constituted so let's look at the 2.925:1 as to how that looks with the RPM ranges:

Roughly 85 MPH to 126 MPH is where I would see the merits of how the bike works with the 2.925:1 FINAL GEARING, now let's all agree that my little 80" EVO engine probably only has a maximum speed of 110 MPH maybe 115 MPH but that's yet to be determined, all I can tell you is that it's no where close to 126 MPH out on a actual road, which means that the gearing is too tall to take advantage of everything the engine has been designed to do, plus if you look carefully at these numbers I don't even get to take advantage of how I built my engine in 5th gear UNTIL 85 MPH, no wonder I am feeling "sluggish" in 5th gear even at 65 MPH - 80 MPH!

[FXR2evo99]

Let's now take this RPM range and look at what the 3.15:1 AND 3.36:1 Final Gearing will show as it relates to the RPM RANGES:

Roughly around 72 MPH - 105 MPH is where I am running 3200 RPMS - 4600 RPMS
AH HAH, so given the cam I am running I am going to find that 5th gear wil run more efficiently with the 3.360:1 FINAL GEARING, the intake close angle of the cam I have chosen which is 34 degrees (which by the way is fairly early) has at least given me a reasonable chance to experience the best elements of how I built my engine starting in 5th gear right at the interstate speeds at 72 MPH, do you know what this means actually it means that from 75 MPH when I wick the throttle because of the mechanical help of the gearing I will be able to have a symbiotic relationship between the construct of the engine as well as the merits provided by the "shorter" gearing which will mean from a rider's feel "seat of the pants" that the relationship between wicking the throttle will require less dramatic effort because the efficiency of their working together from 75 MPH - 105 MPH will give me my best power range both mechanically from a gearing stand point as well as from the engine modifications that were done as well.   Now if I were to choose an earlier intake cam I might see those numbers creep down even into the 65 MPH RANGE as well, but that would require another $150.00 for R&D and looking at another cam. 

Now let's look at 4th Gear:
 
85 LBS OF TORQUE 3200 RPMS - 4700 RPMS

4TH GEAR:
WITH A 25.5512" (649MM) AVON REAR TIRE

2.925:1 FINAL                         3.15:1 FINAL         3.360:1 FINAL

50 MPH      2366 RMPS            2549 RMPS             2718 RMPS
55 MPH      2603 RPMS            2803 RPMS             2990 RPMS
60 MPH      2840 RPMS            3058 RPMS             3262 RPMS
65 MPH      3076 RPMS            3313 RPMS             3534 RPMS
70 MPH      3313 RPMS            3568 RPMS             3806 RPMS
75 MPH      3550 RPMS            3823 RPMS             4078 RPMS
80 MPH      3786 RPMS            4078 RPMS             4349 RPMS                   
85 MPH      4023 RPMS            4332 RPMS             4621 RPMS
90 MPH      4260 RPMS            4587 RPMS             4893 RPMS
95 MPH      4496 RPMS            4842 RPMS             5165 RPMS
100MPH     4733 RMPS            5097 RMPS             5437 RMPS
105MPH     4970 RMPS            5352 RMPS             5709 RMPS
110MPH     5206 RMPS            5607 RMPS
115MPH     5443 RMPS
120MPH     5680 RMPS


3RD GEAR:

2.925:1 FINAL                         3.15:1 FINAL         3.360:1 FINAL

35 MPH      2114 RPMS            2237 RPMS             2429 RPMS
40 MPH      2417 RPMS            2602 RPMS             2776 RPMS
45 MPH      2719 RPMS            2928 RPMS             3123 RPMS
50 MPH      3021 RPMS            3253 RPMS             3470 RPMS
55 MPH      3323 RPMS            3578 RPMS             3817 RPMS
60 MPH      3625 RPMS            3904 RPMS             4164 RPMS                   
65 MPH      3927 RPMS            4229 RPMS             4511 RPMS
70 MPH      4229 RPMS            4554 RPMS             4858 RPMS
75 MPH      4531 RPMS            4879 RPMS             5205 RPMS
80 MPH      4833 RMPS            5205 RMPS             5552 RMPS
85 MPH      5135 RMPS            5530 RMPS             
90 MPH      5437 RMPS


2ND GEAR:

2.925:1 FINAL                         3.15:1 FINAL         3.360:1 FINAL

25 MPH      2126 RMPS            2290 RPMS             2442 RMPS
30 MPH      2551 RPMS            2747 RPMS             2931 RPMS
35 MPH      2976 RPMS            3205 RPMS             3419 RPMS
40 MPH      3402 RPMS            3663 RPMS             3907 RPMS
45 MPH      3827 RPMS            4121 RPMS             4396 RPMS
50 MPH      4252 RPMS            4579 RPMS             4884 RPMS
55 MPH      4677 RPMS            5037 RPMS             5373 RPMS                   
60 MPH      5102 RPMS            5495 RPMS           
65 MPH      5528 RPMS           


1ST GEAR:

2.925:1 FINAL                         3.15:1 FINAL         3.360:1 FINAL

20 MPH      2470 RPMS            2660 RPMS             2838 RPMS
25 MPH      3088 RPMS            3326 RPMS             3547 RPMS
30 MPH      3706 RPMS            3921 RPMS             4257 RPMS
35 MPH      4343 RPMS            4656 RPMS             4966 RPMS
40 MPH      4964 RPMS            5321 RPMS             5676 RPMS
45 MPH      5558 RMPS

As you can see you are not even on the peak torque numbers for 4th gear until 75 MPH roughly which is just another example of how inefficient you are running your engine when in 4th gear at 55 MPH no wonder the bike feels as though it is lagging. So you aren't on your peak torque numbers for 4th gear with the 2.925:1 FINAL GEAR RATIO until 75 MPH - 91 MPH. 

Where as with the 3.360:1 FINAL GEAR RATIO you are on the peak numbers from 65 MPH - 80 MPH.  Which if you look closely provides you a seamless power shift from 4th to 5th while staying completely within the power range of the cam. Which also makes running in 4th gear from 65 MPH - 80 MPH very efficient. 

What you are hopefully seeing is that by moving to "Shorter" Gearing or to the 3.360:1 FINAL GEAR RATIO is that you are creating a union between both the mechanical gearing of the bike along with the engine dynamics as to how it has been modified.  If one were to choose a later intake close angle cam this would only prove this more worthy.

Essentially in 4th Gear the 3.360:1 FINAL GEARING allows the bike at 65 MPH - 75 MPH to run at the peak Torque Numbers making the bike feel stronger 10 MPH sooner than the 2.295:1 FINAL GEARING does and essentially allows one to keep their bike in 4th Gear until 75 MPH.

continuation of these thoughts in reply #12.

[ltank]

   I see that you swapped ratios abit. What did you settle on. Are you using the stock  gears in the 5 speed tranny? I have a 2000 FXR4 CVO that has the 25 motor/36 basket and 32 tranny/65 rear wheel. It runs 80mph at 3,000 RPM best I can tell. It had a fair take off even with the tall gearing. My motor at the time  had cam/carb/pipes with a little less than the power you have. What sucked was running 55 to 65 MPH. 60 MPH 4th gear was 3k or 60 MPH 5th gear about 2,200 RPM chugging the motor.
   5th gear generally is not used unless I am going faster than 65 MPH. It seems there is a big gap wetween 4th and 5th with the stock tranny gear sets. I talked to Baker and they did not understand the gap that I was refering to? The FXR4 manuel is a supplement and does not detail the tranny gearing. The FXR 2/3 manuel shows
1st-9.39  2nd-6.46   3rd-4.60  4th-3.59   5th-2.92. The difference between the gearing lessens as you shift 3rd-4th and 5th. A 6 speed tranny help? But the gearing would be too tall if keeping the 32/65 sprockets and they would need changing. What I would end up with is about the 6th would be about like my 5th but have more gears to pick from.
Maybe I don't understand the ratio thing.  My feeling will not be hurt if can explain to me.
 I now have a S&S V111. I will be installing a Barnett Scorpian Clutch soon. My clutch slips when hitting it riding two up. I know ther are few options for internal tranny gearing.

[FXR2evo99]

Itank~

".....I see that you swapped ratios abit. What did you settle on. Are you using the stock  gears in the 5 speed tranny? I have a 2000 FXR4 CVO that has the 25 motor/36 basket and 32 tranny/65 rear wheel. It runs 80mph at 3,000 RPM best I can tell. It had a fair take off even with the tall gearing. My motor at the time  had cam/carb/pipes with a little less than the power you have. What sucked was running 55 to 65 MPH. 60 MPH 4th gear was 3k or 60 MPH 5th gear about 2,200 RPM chugging the motor.
   5th gear generally is not used unless I am going faster than 65 MPH. It seems there is a big gap wetween 4th and 5th with the stock tranny gear sets. I talked to Baker and they did not understand the gap that I was refering to? The FXR4 manuel is a supplement and does not detail the tranny gearing. The FXR 2/3 manuel shows
1st-9.39  2nd-6.46   3rd-4.60  4th-3.59   5th-2.92. The difference between the gearing lessens as you shift 3rd-4th and 5th. A 6 speed tranny help? But the gearing would be too tall if keeping the 32/65 sprockets and they would need changing. What I would end up with is about the 6th would be about like my 5th but have more gears to pick from.
Maybe I don't understand the ratio thing.  My feeling will not be hurt if can explain to me.
 I now have a S&S V111. I will be installing a Barnett Scorpian Clutch soon. My clutch slips when hitting it riding two up. I know ther are few options for internal tranny gearing...."

I am going to run a final gear ratio of 3.36:1, and I am getting there by leaving the primary set up alone, I am however having to go into the primary to get to the back of it and remove the transmission pulley/sprocket and replace the OEM sprocket from a 32T to a Andrews 30T and then I am replacing the 65T rear wheel sprocket and putting on a HD OEM 70T Sprocket (remember the part number is specific to a 3/4" axle, don't forget this there are plenty of 70T later sprockets out there for a 1" axle i.e.: 2002+ dynas, softails, and touring bikes, but all FXR2 and FXR3 owners MUST have a 3/4" axle sprocket set up).  Also changing the secondary belt from a 133T to a 136T belt, I explained this all above. Nothing was modified to get this FINAL GEARING of 3.360:1 in the transmission case.

Itank all CVO FXR's have the SAME gearing with the same set up.....whether one has a 1999 FXR2 or 1999 FXR3, or 2000 FXR4 they are all set up the same....just remember however your 2000 FXR4 has the 1" axle "I believe" for the rear wheel I know you have the 1" axle for the front wheel.....but I have never looked at the rear wheel....so your swing arm may or may not be the same part number since it may have to be a bit larger to accommodate the 1" rear sized axle....but I am not sure of this and haven't spent any time actually researching such information....since I don't have an FXR4.  I will leave that all up to you FXR4 owners to spill the beans on that issue....The affected parts that would be different for FXR2 and FXR3 owners as compared to FXR4 owners would of course be the rear swing arm which Harley refers to as the Rear Fork in the Parts book, the rear axle, and of course the rear brake caliper which we know is also different matching the newer twin cam versions of brake calipers that are on all model bikes up to 2006 (except for dynas, I believe), and the rear wheel sprocket as well possibly being a different part number from us 1999 FXR2 and FXR3 owners.  

You have described effectively the issues I have had with my bike, I like more torque regardless of what gear I am actually in.....than either the 3.153:1 final gearing that a twin cam bike offered with the carbed bikes of 1999-2001 and all bikes starting in 2002 through 2006 or what I feel my 2.925:1 Final Gearing seems to provide me with my FXR2.  I know what I have done to my engine to build quickness and I feel as you do that I am basically in "no man's land" with the gearing as presently constituted at 55-70 MPH which really I have no use for 5th gear right now until I get above 70 MPH.  It's almost as if the 5th gear for our CVO FXR's is an over drive gear.....and really has no use until you are going 75 MPH.  It simply leaves you either with the engine revving too little with the RPMS until you get into the 75 MPH which is where 5th gear feels like you are back within the power band.  I can provide specifics....I just haven't provided them above yet, but suffice it to say, I have such data, it just takes time to write it all out.

As Jerry Branch was trying to articulate as well as Bill Rook, everything is a compromise.....and how can one get the most bang for their buck $$$$ which is the ultimate goal of course.  You seem to be describing the difficulties very well of the issues associated with present gearing....As I am writing this I fail to remember when our highways changed from 55 for interstate MPH to 75 MPH, but if our highways all were posted at 55 MPH max speed our gearing would not perhaps be as big of an issue, it's right where you are in that tweener location of as you said 55 MPH to 65 MPH.....which is how this gearing modification will help to resolve.  Combine any engine modifications that one has done....and now you have only exacerbated the issue further at least in my opinion.

It's funny actually you never hear of any FXR owners that own a 1989-1993 3.37:1 Final Geared bike as being buzzy or uncomfortable or anything for that matter....they all seem to love it.  

(to be continued below)

[FXR2evo99]

I have recently had a 10 minute conversation with an owner of a 1993 FXLR which has 3.37:1 final gearing and he has owned a 2000 Road King with 3.37 Final Gearing as well as 2 other FXR's which one was a 1990 FXR which was stolen, as well as a 1994 FXLR that he just sold last fall, so here is a guy that has owned a total of 3 FXR's as well as 1 road king, and a softail as well, he sold the softail as he didn't like it, and given the 3 FXR's he has owned he PREFERS the 3.37:1 Final Gearing of both the 1990 and 1993 FXR bikes.  He obviously sold the 1994 FXR with the 3.15:1 Final Gearing.  I specifically asked him about all of this, and his thoughts....as it is tough to talk with anyone that has paid much attention to their gearing, and he actually was very sensitive to his experience, he wouldn't own a FXR without 3.37:1 Final Gearing and had even spent time talking with other bike builders about this issue of which one in particular felt the 3.37:1 final gearing was very crucial to the success of any bike.   I felt this was an interesting conversation of course.  

So I have written this thread to provide some background and some R&D for the merits of it....once I have spent some time with the build and the gearing change I will of course report my findings....personally though, I am quite excited about the merits of this modification, as on paper they look great, just like they did on the modification for my 2002 RKC.  In fact when it comes to my RKC I still have a 25T compensating sprocket and a entirely brand new 36T clutch shell sprocket and friction plates (the entire assembly) waiting all these years to go back in if I felt the 3.37:1 Final Gearing modification was not acceptable to me on that bike, and 6 years later the parts just sit nicely wrapped up and boxed, the modification back would only take about 3 hours or less and then I would be back to 3.15:1 Final Gearing but I absolutely love the feeling of the 3.37:1 Final Gearing with the way I built that engine....so I feel my response for the FXR2 will be equally positive but if it is not.....I have no problems going back the other way.....BUT when you study very carefully the merits of going to the "Shorter" gearing with the way I built my engine to run and given that I am a bonifide confessed Torque Junkie, I am pretty sure the results will be very nice, and probably will be kicking myself for not having done it sooner.  If you were to go back to some old threads I participated in and read carefully I spent some time detailing why I wouldn't put the 3.37:1 Final Gearing in our CVO FXR's which have the 2.925:1 Final Gearing set up, but now that I have the engine modification that I completed FEB 2011, I know the performance of the bike is missing this last bit of the recipe.....so I am going to find out.....

Regards,

Tim

[FXR2evo99]

If you study these charts closely enough and study the way you ride your bike, you will discover that 4th gear with the 3.360:1 FINAL GEARING will become more efficient and 5th gear will become actually much more usable.....which is just another benefit from the actual modification as well.

I will add more later....

[FXR2evo99]

probably only need this spot to add any additional final information so I wil save this spot as well if I can think of anything else to write....

now it's just all about comments if there are any....

[FXR2evo99]

Thanks for this tip from Jamesbutler:

Overall/Final Gearing Ratio is determined by multiplying the inner primary value by the outer primary value.  So, to determine the inner primary value, you divide the number of teeth on the clutch sprocket by the number of teeth on the compensating sprocket, e.g., 37/24 = 1.5417, rounded off to 1.54.  Then to determine the outer primary value, you divide the rear wheel sprocket by the transmission sprocket, e.g., 70/32 = 2.1875 or rounded off to 2.19.  Thus, by multiplying the inner primary value 1.54 by the outer primary value 2.19, you get 3.3724 or rounded off to 3.37.

To recap:
Inner primary ratio x Outer primary ratio = Overall ratio,
Inner primary = # of clutch sprocket teeth divided by # of compensating sprocket teeth, and
Outer primary = # of rear wheel sprocket teeth divided by # of transmission sprocket teeth, so
Inner primary (37/24)   x   Outer primary (70/32)   =   1.54 x 2.19 = 3.37

or

Inner primary ratio x Outer primary ratio = Overall ratio,
Inner primary = # of clutch sprocket teeth divided by # of compensating sprocket teeth, and
Outer primary = # of rear wheel sprocket teeth divided by # of transmission sprocket teeth, so
Inner primary (36/25)   x   Outer primary (70/30)   =   1.44 x 2.33 = 3.360

Regards,

Tim