2018+ Softail Models Breakout

Maximum Acceleration Shift Points & Rev Limiter

Thread Tools
 
Search this Thread
 
Old Jul 10, 2019 | 06:39 PM
  #1  
Hulkss's Avatar
Hulkss
Thread Starter
|
HDF Community Team
10 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Sep 2013
Posts: 2,371
Likes: 2,339
From: Wisconsin
Community Team
Default Maximum Acceleration Shift Points & Rev Limiter

I had my bike (2019 FLHCS) tuned on a Dynamometer with the Harley Pro Street Tuner. The RPM limit can be set as high as 6400 with this tuner. Do I need to go this high?

I took my "Dyno Sheet" and plotted the torque curve data at 500 rpm intervals extrapolated a little out to 6000 RPM.

Knowing this engine torque data, combined with the bikes overall gear ratios, the torque at the rear wheel can be calculated. I did that for each gear and plotted it with road speed for the stock rear wheel diameter.

To accelerate the quickest, you want to keep rear wheel torque as high as possible. That means shifting at redline or sooner if the next higher gear will give you more rear wheel torque. For my bike, there is no performance gain in revving the motor higher than the points shown. That is due to the drop in torque at high rpm.

Since I'm never riding around in first gear, I'm going to set the rev limiter at 5900. That way I protect the engine as much as possible while keeping maximum performance for overtaking.

Dynamometer Run

Plotted Torque Data from Dyno
 

Last edited by Hulkss; Jul 10, 2019 at 08:49 PM.
Reply
Old Jul 10, 2019 | 06:53 PM
  #2  
FLS103's Avatar
FLS103
Road Warrior
10 Year Member
Liked
Loved
Community Favorite
Joined: May 2014
Posts: 1,962
Likes: 245
From: Triune, TN
Default

Very cool! My max torque is about 200 rpm lower than yours, gear ratios are the same but the Fat Bob rear tire diameter is different, I would think my shift points would be close. I noticed my rev limiter is set at 7000, know dang well that I do not need to rev that high
 
Reply
Old Jul 10, 2019 | 06:56 PM
  #3  
FLS103's Avatar
FLS103
Road Warrior
10 Year Member
Liked
Loved
Community Favorite
Joined: May 2014
Posts: 1,962
Likes: 245
From: Triune, TN
Default


posted as you instructed
 
Reply
Old Jul 10, 2019 | 08:25 PM
  #4  
Hulkss's Avatar
Hulkss
Thread Starter
|
HDF Community Team
10 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Sep 2013
Posts: 2,371
Likes: 2,339
From: Wisconsin
Community Team
Default

Here's the results for that FXFBS with the CR-480 stage II:


CR-480 Stage II 114
 
Reply
Old Jul 10, 2019 | 08:38 PM
  #5  
FLS103's Avatar
FLS103
Road Warrior
10 Year Member
Liked
Loved
Community Favorite
Joined: May 2014
Posts: 1,962
Likes: 245
From: Triune, TN
Default

Very much appreciated, thank you!
 
Reply
Old Jul 10, 2019 | 08:53 PM
  #6  
Hulkss's Avatar
Hulkss
Thread Starter
|
HDF Community Team
10 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Sep 2013
Posts: 2,371
Likes: 2,339
From: Wisconsin
Community Team
Default

Save a little wear and tear from too much rpm and go quicker at the same time!

Shifting 3rd to 4th at 100 mph when passing someone must be fun!!
 

Last edited by Hulkss; Jul 10, 2019 at 08:56 PM.
Reply
Old Jul 10, 2019 | 09:09 PM
  #7  
FLS103's Avatar
FLS103
Road Warrior
10 Year Member
Liked
Loved
Community Favorite
Joined: May 2014
Posts: 1,962
Likes: 245
From: Triune, TN
Default

Originally Posted by Hulkss
Shifting 3rd to 4th at 100 mph when passing someone must be fun!!
I have probably done this lol.
 
Reply
Old Jul 11, 2019 | 10:42 PM
  #8  
Superdog3:16's Avatar
Superdog3:16
Outstanding HDF Member
Joined: Nov 2018
Posts: 3,421
Likes: 726
From: Tiffin,Oh
Default

Newbie here ....BE NICE!....... So, with a M8 softail bike,stage 1,for maximum acceleration, more or less shift at what? 4K? T I A.
 

Last edited by Superdog3:16; Jul 11, 2019 at 10:46 PM.
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Times Harley-Davidson Chucked Tradition Out the Window

 Verdad Gallardo
story-1

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-2

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-4

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-5

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-6

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-7

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-8

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-9

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
Old Jul 12, 2019 | 07:07 PM
  #9  
Hulkss's Avatar
Hulkss
Thread Starter
|
HDF Community Team
10 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Sep 2013
Posts: 2,371
Likes: 2,339
From: Wisconsin
Community Team
Default

Originally Posted by Superdog3:16
Newbie here ....BE NICE!....... So, with a M8 softail bike,stage 1,for maximum acceleration, more or less shift at what? 4K? T I A.
Here's the power and torque for a stock 107 Fat Bob as measured by Cycle World", followed by the best shift points for maximum acceleration.


 
Reply
Old Jul 12, 2019 | 07:21 PM
  #10  
Superdog3:16's Avatar
Superdog3:16
Outstanding HDF Member
Joined: Nov 2018
Posts: 3,421
Likes: 726
From: Tiffin,Oh
Default

Thanx! I shoulda known a helluva lot tighter!
 
Reply



All times are GMT -5. The time now is 09:12 AM.

story-0
7 Times Harley-Davidson Chucked Tradition Out the Window

Slideshow: Harley-Davidson built its reputation on nostalgia, but every so often, the company took a hard left turn into the future.

By Verdad Gallardo | 2026-05-20 11:18:19


VIEW MORE
story-1
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-2
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-3
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-4
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-5
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-6
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-7
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-8
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-9
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE