REPRINT FROM OLD HTT: TWIN CAM 24/37 PRIMARY GEARING CHANGE (ADVICE)

[ClassicRider2002]

DISCLAIMER: THIS IS A REPRINT TOPIC FROM "OLD" HTT

I have saved many great topical discussions as "links" over the years and would hate to see these lost, so I am reprinting this TOPIC here, which may "perhaps" help some.

TOPIC:  TWIN CAM 24/37 PRIMARY GEARING CHANGE (ADVICE)  08-11-2004
   

From: SKEETERJIM  (Original Message) Sent: 8/11/2004 6:51 PM   Message 1 of 33 in Discussion
Thinking about the "next" winter project for flstf TCB.  Im happy with the motor's high rpm power band
The motor is:
95", Hicomp pistons, SE heads worked,port matched SE intake, CV44, Crane ignition, SE211 cam.

I would like to squeeze more out the the bottom end if possible without changing the motor setup.

Here is what I am thinking.
24/37 and live with the rpms at about 4000 at highway speeds
24/37 then add a six speed with the original gear ratios
use a 21T instead of a 24T and of course six speed
21T and Baker 6speed DD6 with 0.80 final gearing.

Anyone running these setups?
Pros/Cons?
Thanks Jim

[ClassicRider2002]

From: HokieRich1 Sent: 8/12/2004 5:17 AM   Message 2 of 33 in Discussion
Changing to the 3.37 gears makes a nice difference in a heavier bike. It made more difference than I would have thought in top gear roll ons. I dont find the higher rpms to be an issue as there isnt that much of a change. What I do like is it helps keep from lugging the engine and saves some down shifts from high gear. As far as the six speed, I personally would have a hard time justifying the cost. 


From: jmorton10 Sent: 8/12/2004 5:29 AM   Message 3 of 33 in Discussion
I agree, swapping to the 3.37 was one of the best things I ever did to my bike.  I was hesitant to do it for the longest time because I was afraid I wouldn't like it at cruising speed, I hardly even notice the additional revs at 70 mph however.   
I would love to have a six speed but there is NO WAY I am spending that kind of money just to drop a few hundred rpm's at 80 mph.  ~John
   

From: RespectedTompat Sent: 8/12/2004 5:38 AM   Message 4 of 33 in Discussion
Jim, sounds as if you want better hole-shot and still be able to cruise highway? Another option might be to get a 6-speed with first 5 gears already lower and then 6-gear OD. I think Baker has one of these...I wouldn't do the 21T without the 6-speed.


From: Cold.Rider Sent: 8/12/2004 7:06 AM   Message 5 of 33 in Discussion
I ran 800 miles on a trip this summer at 80 mph with my 3.37 gears.  The motor absolutely loved running 3400-3500 rpm.  Still got about the same gas milage as I did when I had the taller gears in it.


From: Puhb1 Sent: 8/12/2004 8:07 AM   Message 6 of 33 in Discussion
Baker direct drive 6 speed kit. If you are considering that much expense 2k+ - the whole kit changes all the ratios to give better gear splits and better acceleration with a slower cruise rpm.
     

From: Thunderslide Sent: 8/12/2004 8:07 AM   Message 7 of 33 in Discussion
I was with Cold Rider on that trip, I have a carb bike and found a little loss in fuel mileage. but we were in a heavy cross wind and it seemed that we were all down a bit. Cold rider is injected..  other than that is it a completely streetable combination that really works well.  try it if you don't like it, you'll loose $ but selling the parts will not be a tuff task.
   

From: eogtech Sent: 8/12/2004 8:15 AM   Message 8 of 33 in Discussion
Alright...a little help here please.  I have read about a 3.37  ratio often and heard some good remarks about it.  My "boy" is about 700 pounds with 350 pounds in riders.  I think that I should consider this as an option.  What has to be done and what parts are needed?  Is it just a front sprocket and chain, or the clutch basket too?
   

From: jmorton10 Sent: 8/12/2004 10:07 AM Message 9 of 33 in Discussion
37846-99a clutch    $256.00
40269-85a sprocket(24T)    $50.76
Those are 20% off Hales prices, you replace the compensator sprocket & clutch shell.  ~John   


From: Wiggles Sent: 8/12/2004 10:25 AM   Message 10 of 33 in Discussion
How many service hours should an honest shop charge to change the comp sprocket & basket?
   

From: Cold.Rider Sent: 8/12/2004 10:55 AM   Message 11 of 33 in Discussion
You can do it yourself in about 2 hours, taking your time.  It's easy, we'll be happy to walk you through it.
 

From: SKEETERJIM Sent: 8/12/2004 12:49 PM   Message 12 of 33 in Discussion
Thanks to all the replies.  This site has the best collection of knowledge about HD motorcycles.  Jim
   

From: joepenoso Sent: 8/12/2004 3:08 PM   Message 13 of 33 in Discussion
Hey guys I heard you could just buy a front primary sprocket 2 teeth smaller and if you have a pre 2002 machine flip the primary adjuster to tension the chain.Correct me if I'm wrong and quite frankly I've never done it
and I'm curious if somebody actually tried it and put some miles on one.  Thanks  joepenoso


From: JSachs1 Sent: 8/12/2004 6:20 PM  Message 14 of 33 in Discussion
Joe,
If you're going to make the change,you can use a sidecar primary chain.Also Diamond makes a variety of primary chains that can be used.Application would be for Dyna or Softail.  John

   

From: joepenoso Sent: 8/12/2004 8:35 PM   Message 15 of 33 in Discussion
John, thanks.  I never considered there might be a side car gearing option from harley and never knew Diamond made various sized primary chains  joepenoso 


From: eogtech Sent: 8/13/2004 5:54 PM   Message 16 of 33 in Discussion
Oldschool,  How does the 24 tooth work with an HB125?  Does the chain need to be changed?


From: Fatboy_SirGarfield Sent: 8/14/2004 4:12 AM Message 17 of 33 in Discussion
Ever looked at a TwistGear setup ?
TWIST GEAR  <~~~CLICK, VIEW, & READ

From: FLHT1550 Sent: 8/14/2004 7:14 PM   Message 18 of 33 in Discussion
Could you please tell me if you turn the whole bracket upside down or just the shoe ? also could you let me know what kind of RPM's your running at 80MPH. Also what model of HD your running it on.

     
From: eogtech Sent: 8/15/2004 7:35 AM   Message 19 of 33 in Discussion
What happens to speedo indication when sprockets are changed.  I understand that speed sensor is at the crank.  How does you correct it?


From: harleyhog  Sent: 8/15/2004 7:57 AM   Message 20 of 33 in Discussion 
Speed sensor is in/on the tranny. It's further down the chain in a manner of speaking, so no change...


From: FLHT1550 Sent: 8/15/2004 9:04 AM   Message 21 of 33 in Discussion
Has anyone tried the 21 tooth motor sprocket with the 36 tooth basket on a bagger. And if so how high are the RPM's at 75 - 80 mph highway speeds. I read somewhere on a dyno sheet that somebody had gone with a 22 tooth motor sprocket and stock basket on a 2001 FL model and it was suppost to be a torgue monster. Any thoughts


From: ederdelyi Sent: 8/15/2004 10:20 AM   Message 22 of 33 in Discussion
If you want to see what its like with the 21/36 setup, just run in 4th gear at 75-80 MPH.

Stock setup: primary 25/36 = 1.44, final 32/70 = 2.19
5th gear = 1.00, 4th gear = 1.21
Stock setup in 5th gear: 1.44*1.00*2.19 = 3.15 final (~=3200 RPM @ 77 MPH)
Stock setup in 4th gear: 1.44*1.21*2.19 = 3.81 final ( ~= 3850 RPM @ 77 MPH)

21/36 primary = 1.71
21/36 setup in 5th gear 1.71*1.00*2.19 = 3.74 final (~= 3800 RPM @ 77 MPH)

Regards,
Ed

[ClassicRider2002]

From: FLHT1550 Sent: 8/15/2004 10:41 AM   Message 23 of 33 in Discussion
Thanks Ed, Don't think thats the combination  i'm looking for.


From: 02roadcling Sent: 8/15/2004 11:02 AM   Message 24 of 33 in Discussion
ED,
Since I dont have a tach yet I was just wondering what rpm I am turning in first gear at 75-80 mph? Just kidding as if......
I always enjoy your posts Ed! Thankyou for helping me gain more of an undersanding about my bike. I wish I would of met you and others here before I made my purchase, would of saved me some bucks on unneeded parts and sped up the speed process for sure.  02roadcling
   

From: RespectedTompat Sent: 8/16/2004 9:50 AM   Message 25 of 33 in Discussion
Jim, as you know, this is the setup I have and I love it. However, the 6th gear is still a bit more than we both need with our late cams. Take my advice on this and you will be a little happier. Go with something just a tad more than the 3.37 if you are going the 6-speed route. If I had to do it over right now, I would do the SE 6-speed with a 23T and matching chain!

The 3.37 is perfect for me, but the 6th gear wants you to be crusing at like 85 MPH with the 211 cam. The 23T compensator should be perfect. It would also help give you a tad bit better holeshot than me;)

Warning, some people mentioned that the HB-125 works with the 24/37 setup, but I had to modify mine in order for it to fit right. The new position of the chain with 24/37 caused my chain tensioner to sit lower than it liked to be. I had to remove some material off the back of the HB-125 to get proper alignment.  You might ought to try the gearing change before making the 6-speed leap. You may like it just the way it is...Let me know if you want to install this, and I will help you out if you need it.
Mine is '04 Fat Boy...
   

From: Thunderslide Sent: 8/16/2004 10:29 AM Message 26 of 33 in Discussion
what do you have for a bike? is there a size/shape diverence in the primarys between the various models. I know the cover looks different but are the other subtle diferences? that might change the mounting location of the tensioner? 


From: FLHT1550 Sent: 8/16/2004 6:06 PM   Message 27 of 33 in Discussion
Can you provide a part number or application that has a 23 tooth compensating sprocket. When I look for a 23 tooth there always the older style ramps like the shovel and early evo. had. Anyone had the answer ?   I'm looking of one to fit 2002 bagger.


From: SKEETERJIM Sent: 8/16/2004 9:14 PM   Message 28 of 33 in Discussion
Tom, I checked on the 23T/chain combo.  It puts the final drive ratio at more than 3.5
DS part# 1212-0010 $335.95

What do you think about changing the transmission pulley to a 30 Tooth? ($135.00)
and a rpm compensation module $78

Close to the same final gear ratio.  You know since I brought this up that it is illegal to use this combo.  Jim


From: joepenoso Sent: 8/16/2004 9:24 PM   Message 29 of 33 in Discussion
I'll Bite? Why's it illegal?  joepenoso


From: SKEETERJIM Sent: 8/16/2004 9:30 PM   Message 30 of 33 in Discussion
I thought of it first.   NoDisrespectTom and I have the same bikes.
   

From: RespectedTompat Sent: 8/16/2004 9:53 PM   Message 31 of 33 in Discussion
Jim, you will have 3.50 only if you change the clutch basket sprocket as well. I only meant to change the compensator to 23t which will give you 3.42 final. If you do the 6-speed, you will be glad you did the 23t.

I think the part number 1212-0010 is for the 21t and is for the FLT/FLR. The softtail 21t # is 1212-0014 and the 23t is 1212-0016. CycleSpot price with chain is $292.28 which is cheaper than Hales discounted 24/37 setup price and is $43.67 cheaper than the price you were quoted. Plus, if you decide on 23t you do not have to get machine shop to press clutch basket together.  You need to get the RPMs up quick with your pipes and cam. This should do it...


From: RespectedTompat Sent: 8/16/2004 9:56 PM   Message 32 of 33 in Discussion
Does this mean you can't use my idea of the 23t and 6-speed since it was my idea? LOL, j/k....
I have been checking out those Apes and solo seat. About to push the button and confirm order...


From: RespectedTompat Sent: 8/16/2004 9:58 PM   Message 33 of 33 in Discussion
Imagine the look on JK's face when you blow him out of the hole and still have little more top end with 6th gear!

[ClassicRider2002]

TwinCam : 3.37 Gearing

From: Harleyrider  (Original Message) Sent: 10/26/2004 4:01 PM    Message 1 of 4 in Discussion 
I looked back on all the posts clear to July.  Didn't find what I was looking for.  Can someone please post the necessary parts and numbers for 3.37 final drive.  It would be for a 05 RKC.  I was wondering if it makes that much difference and what is the 'out of pocket' on this.   I know this has been discussed, however, I can't find it.   Thanks in advance! 

     
From: L-Bar Sent: 10/26/2004 4:51 PM   Message 2 of 4 in Discussion
Out of pocket will be about $300 for parts and then you have primary fluid and gasket. This is if you buy from Benjy's where Jenni works.   It is about a 6% difference in gearing.  I have a Road King and ride with someone that has an 04 Dyna Low Rider and over the same course and speed they get .1 gallon less than I do.  I have the 3.37 as I live up high, have a heavy bike and am usually loaded and I am heavy at 220 lbs.


From: jmorton10 Sent: 10/26/2004 6:58 PM  Message 3 of 4 in Discussion

37846-99a clutch    $256.00
40269-85a sprocket(24T)    $50.76

prices from Jenni

~John  


From: Hillshog3 Sent: 10/27/2004 1:19 PM   Message 4 of 4 in Discussion
I have been using the 23/37 with the stock chain for years now. Works great, I did not need to turn my shoe upside down like some have said. Along with the six speed for the 65+ mph. I have the all around best. If I want to play the first five will give me all I want.  And when I hit the interstates I have the .86 OD. Low rpm on the HWY     HH3  

[ClassicRider2002]

While I realize this "THREAD" goes a ways back I feel the content warrants it being brought over here to the New HTT Site, hopefully it is helpful to others.

Anything added beyond this point is new information.

Regards,

"Classic"

[ClassicRider2002]

I actually have a excel spread sheet that was provided within a THREAD here at HTT by:
From: Fuzznut5197 Sent: 6/13/2008 7:01 PM
Anyone have any use for this driveline spreadsheet? It was posted here back in 2003, and I thought is was saved somewhere in HTT, but I can't find where.

Hopefully all will be able to down load the EXCEL PROGRAM below next to the "paper clip"

If you plug in your actual gearing (comp sprocket "T"ooth size, clutch shell basket/ring gear "T"ooth size, rear wheel sprocket "T"ooth size, transmission "T"ooth size as well as rear wheel diameter then it will factor RPMS and such which would aid you in determining what level of gearing you might benefit most from........then if you wish to ponder some other options for your comp gear or your clutch shell basket gear or perhaps your secondary gearing which might require a different belt you can see what might create the biggest bang for your buck.....

[NOTE: Please remember that putting your cursor next to the paper clip icon below will allow you to open this EXCEL PROGRAM, if you desire simply choose to save the program to your computer as well]

[attachment removed after 60 days by system]

[ClassicRider2002]

Hello Everyone~~~

Through out all of the "old" THREADS that deal with the 3.37 Gearing Modifcation to our TWIN CAM BIKES I really enjoyed reading them....and after all of the valuable input from everyone whom posted, I eventually did the MODIFCATION to my 2002 RKC.  Like many before me have stated and I must concur, this MODIFICATION has to be ONE OF THE ABSOLUTELY BEST MODIFICATIONS I have done to my "BAGGER", it's such a wonderful "bang" for the buck invested....

Thus I put together a detailed THREAD about the modification, if you are interested in reading about such Simply CLICK, VIEW, & READ the Attached "LINK" below:

3.37 MODIFICATION GEARING INSTRUCTIONS FOR 2002-2006 TWIN CAMS 

I happen to be "ClassicRider" @ V~TWIN FORUM.

Regards,

"Classic"