Engine Mechanical Topics Discussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.

107 with 551?

Thread Tools
 
Search this Thread
 
Old Sep 15, 2017 | 09:35 AM
  #1  
Mac daddy 103's Avatar
Mac daddy 103
Thread Starter
|
Road Master
Joined: Dec 2013
Posts: 1,072
Likes: 212
From: Boston,Ma
Default 107 with 551?

Ok so now I'm on the hunt to upgrade to a 107, not looking for anything wild but looking for a mild setup. I already have the S&S 551 cams installed so my next Question is will the cams I have, work with a 107 or does anyone have this setup and happy with it?

Next Question, which brand of 107 is king out there, should I get heads or will the stock head work fine.

Thanks for any input
 
Reply
Old Sep 15, 2017 | 10:12 AM
  #2  
2013_FLHTK's Avatar
2013_FLHTK
Road Warrior
10 Year Member
Liked
Loved
Community Favorite
Joined: Oct 2013
Posts: 1,399
Likes: 1,040
From: Seabrook, NH
Default

Looking forward to answers here.

Attached is a dyno sheet comparing a 103 to a 107 with heads. Both have the 551 cam installed.
 
Attached Thumbnails 107 with 551?-551_103-vs-heads107.jpg  
Reply
Old Sep 24, 2017 | 11:21 AM
  #3  
iMedic's Avatar
iMedic
Intermediate
Joined: Sep 2017
Posts: 42
Likes: 7
From: Tennessee
Default

I have the S&S 106" bolt in kit with the 89cc SuperStock heads and the 551 Cams, 58mm Throttle Hog with SE Injectors. It's a great set up, mild is what I call it for sure, but I'm in search of even more power, so I'm changing cams. The next step to go without losing bottom end power is the MR103 from S&S.
so who has the best kit? I like S&S. they have been around for decades. They are reliable. Make people can do head work to produce more power, but S&S is tried and true.

Hey 2013 FLHTK, what heads are you running and how do you like your suspension? I'm about to do my suspension next.
 
Reply
Old Sep 24, 2017 | 12:40 PM
  #4  
cdonis's Avatar
cdonis
Outstanding HDF Member
Joined: Jul 2013
Posts: 3,245
Likes: 297
From: Escalon ca
Default

Originally Posted by iMedic
I have the S&S 106" bolt in kit with the 89cc SuperStock heads and the 551 Cams, 58mm Throttle Hog with SE Injectors. It's a great set up, mild is what I call it for sure, but I'm in search of even more power, so I'm changing cams. The next step to go without losing bottom end power is the MR103 from S&S.
so who has the best kit? I like S&S. they have been around for decades. They are reliable. Make people can do head work to produce more power, but S&S is tried and true.

Hey 2013 FLHTK, what heads are you running and how do you like your suspension? I'm about to do my suspension next.
I have a set of mr103s. Cams only with 9000 miles. I built a 124 and have no need for them. Make an offer via private message of interested.
 
Reply
Old Sep 24, 2017 | 01:49 PM
  #5  
2013_FLHTK's Avatar
2013_FLHTK
Road Warrior
10 Year Member
Liked
Loved
Community Favorite
Joined: Oct 2013
Posts: 1,399
Likes: 1,040
From: Seabrook, NH
Default

Originally Posted by iMedic
I have the S&S 106" bolt in kit with the 89cc SuperStock heads and the 551 Cams, 58mm Throttle Hog with SE Injectors. It's a great set up, mild is what I call it for sure, but I'm in search of even more power, so I'm changing cams. The next step to go without losing bottom end power is the MR103 from S&S.
so who has the best kit? I like S&S. they have been around for decades. They are reliable. Make people can do head work to produce more power, but S&S is tried and true.

Hey 2013 FLHTK, what heads are you running and how do you like your suspension? I'm about to do my suspension next.
Send me a PM. Don't want the OP to get off topic.
 

Last edited by 2013_FLHTK; Sep 24, 2017 at 01:54 PM.
Reply
Old Sep 24, 2017 | 02:13 PM
  #6  
djl's Avatar
djl
HDF Community Team
Veteran: Army
15 Year Member
Photogenic
Liked
Joined: Jun 2006
Posts: 12,763
Likes: 2,597
From: san antonio
Community Team
Default

I will buy the 103" dyno in #2 but having a tough time believing the 107" dyno; 130TQ is 1.2 and change per cubic inch which can be achieved but without knowing more about the build configuration and the dyno, not sure I believe it.

I would have second thoughts about running 551 cams in a 107" motor. Even with a .045" head gasket corrected CR is up about 9.8 and CCP approaching 210psi; pushing the envelope for me but, that's just me and I would have to hear from someone running that configuration before pulling the trigger. I understand wanting to keep the cams but a cam change and head work might be the best move with the additional displacement.

You did not mention fuel management in your OP. If you have not installed a fuel management system and had the current build properly tuned, you might invest in a tuner and proper tune. You might find that by optimizing the current configuration, the added performance might allow you to forego the displacement upgrade for the immediate future. Even with a good fuel management system, I would suspect the 551 cams in a 107" configuration to be a tuning challenge.

JMHO.
 

Last edited by djl; Sep 24, 2017 at 02:19 PM.
Reply
Old Sep 24, 2017 | 03:11 PM
  #7  
cdonis's Avatar
cdonis
Outstanding HDF Member
Joined: Jul 2013
Posts: 3,245
Likes: 297
From: Escalon ca
Default

Originally Posted by djl
I will buy the 103" dyno in #2 but having a tough time believing the 107" dyno; 130TQ is 1.2 and change per cubic inch which can be achieved but without knowing more about the build configuration and the dyno, not sure I believe it.

I would have second thoughts about running 551 cams in a 107" motor. Even with a .045" head gasket corrected CR is up about 9.8 and CCP approaching 210psi; pushing the envelope for me but, that's just me and I would have to hear from someone running that configuration before pulling the trigger. I understand wanting to keep the cams but a cam change and head work might be the best move with the additional displacement.

You did not mention fuel management in your OP. If you have not installed a fuel management system and had the current build properly tuned, you might invest in a tuner and proper tune. You might find that by optimizing the current configuration, the added performance might allow you to forego the displacement upgrade for the immediate future. Even with a good fuel management system, I would suspect the 551 cams in a 107" configuration to be a tuning challenge.

JMHO.
Djl, I always like to see those miracle dyno sheets. Far too many overachievers out there it seems.
 

Last edited by cdonis; Sep 24, 2017 at 03:13 PM.
Reply
Old Sep 24, 2017 | 09:17 PM
  #8  
98hotrodfatboy's Avatar
98hotrodfatboy
Seasoned HDF Member
15 Year Member
Liked
Loved
Top Answer: 5
Joined: Mar 2010
Posts: 21,028
Likes: 7,549
From: Poolville
Default

Yeah 130 lbs is hard to believe... Remember TARGET64"s 107 build.. That bike sounded nasty and I believe he hit 129/127,IIRC... But it was a pumped motor with a good deal of machining....

And yes djl, 1.2 is not achievable without good head work...
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-1

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-2

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

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

 Verdad Gallardo
story-4

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

 Verdad Gallardo
story-5

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-6

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-7

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-8

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
story-9

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

 Verdad Gallardo
Old Sep 25, 2017 | 01:39 PM
  #9  
Hillsidecycle.com's Avatar
Hillsidecycle.com
Sponsor
Joined: Dec 2007
Posts: 12,084
Likes: 829
Default

Originally Posted by Mac daddy 103
Ok so now I'm on the hunt to upgrade to a 107, not looking for anything wild but looking for a mild setup. I already have the S&S 551 cams installed so my next Question is will the cams I have, work with a 107 or does anyone have this setup and happy with it?

Next Question, which brand of 107 is king out there, should I get heads or will the stock head work fine.

Thanks for any input

Me thinks that the 551 is a bit short for a 107".
Minimum compression on those, even with a .040" head gasket comes in at 10.0.
Puts the ccp up there at 210 plus.......you ain't gonna like that.
Scott
 

Last edited by Hillsidecycle.com; Sep 25, 2017 at 02:53 PM.
Reply
Old Sep 25, 2017 | 04:06 PM
  #10  
iMedic's Avatar
iMedic
Intermediate
Joined: Sep 2017
Posts: 42
Likes: 7
From: Tennessee
Default

Most all of these cams come with the EZ Start design and therefore the CCP shouldn't be a problem
 
Reply



All times are GMT -5. The time now is 11:08 PM.

story-0
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-1
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-2
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-3
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-4
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-5
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-6
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-7
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-8
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
story-9
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Slideshow: Graeme Billington's left-hand-drive Shovelhead is as much about problem-solving as it is about classic Harley form.

By Verdad Gallardo | 2025-12-30 11:27:08


VIEW MORE