Dyna Glide Models Super Glide, Super Glide Sport, Super Glide Custom, Dyna Glide Convertible, Super Glide T-Sport, Dyna Glide Police, Dyna Switchback, Low Rider, Street Bob, Fat Bob and Wide Glide.
Sponsored by:
Sponsored by:

PM 6 piston calipers on 08 Street Bob - No go!!!

Thread Tools
 
Search this Thread
 
Old Mar 29, 2008 | 09:51 PM
  #1  
vladt's Avatar
vladt
Thread Starter
|
Cruiser
Joined: Oct 2007
Posts: 243
Likes: 2
From:
Default PM 6 piston calipers on 08 Street Bob - No go!!!

I was about to place an order for a set of Performance Machine direct bolton 6 piston calipers for my 08 model Street Bob. Luckily, I've asked the quesiton whether their would fit without any modifications. Unfortunately - they will not! The caliper only fits 11 1/2" disc. Indeed, every model SB up to 2008 had the 11 1/2" disc.

However, in their "infinite wisdom" for 2008 HD had changed the disc diameter for 2008 model Street Bob and some other 08 model softails to 11.8". Obviously, a larger disc diameter means better braking performance but once again the aftermarket accessories will no longer fit. This was also the case with risers being "built-in" to top tripple tree which prevents 08 model SB owners from utilising "pull back" handle bars similar to Burleigh.

Is anyone aware of any other slight modifications that factory has introduced on 2008 model Street Bob and that are not widely publicised?

Are there any other 6 piston calipers that will fit 08 Street Bob without modifications?

The obvious solution is to use PM 11.2" disc. However IMHO it would constitute a step back since PM discs are smaller in diameter and semi-floating. While HD discs are fully floating.

So any ideas guys/gals?

ta
Vlad
 
Reply
Old Mar 29, 2008 | 09:55 PM
  #2  
VenturaChop's Avatar
VenturaChop
Road Master
Joined: Apr 2007
Posts: 1,156
Likes: 0
From: oxnard ca
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

why dont u get a 07 front rotar???
 
Reply
Old Mar 29, 2008 | 10:25 PM
  #3  
vladt's Avatar
vladt
Thread Starter
|
Cruiser
Joined: Oct 2007
Posts: 243
Likes: 2
From:
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

Well, I could potentially get an 07 front rotor but it is smaller in diameter. The idea here is to improve braking by changing over to 6 piston calipers. It makes no sense to utilise larger calipers with smaller disc. The resultant braking performance might not improve.
 
Reply
Old Mar 29, 2008 | 10:31 PM
  #4  
VenturaChop's Avatar
VenturaChop
Road Master
Joined: Apr 2007
Posts: 1,156
Likes: 0
From: oxnard ca
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

11.5 and 11.8 is hardly a diffrence man the six piston over a 07 disk would produce better stopping over a 11.8 with a stock caliper
 
Reply
Old Mar 29, 2008 | 10:37 PM
  #5  
tomato's Avatar
tomato
Tourer
15 Year Member
Liked
Loved
Community Favorite
Joined: Nov 2007
Posts: 317
Likes: 20
From: Lakewood, IL
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

If you are really after vetter braking, go to the V-Rod twin...Unbelieveable difference.
 
Reply
Old Mar 30, 2008 | 01:28 AM
  #6  
fj4069's Avatar
fj4069
Road Warrior
Joined: May 2006
Posts: 1,342
Likes: 2
From:
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

i had no idea that the 15 thousanths of an inch difference was so large. if the pm 6 piston calipers don't fit i would be surprised.
 
Reply
Old Mar 30, 2008 | 06:24 AM
  #7  
vladt's Avatar
vladt
Thread Starter
|
Cruiser
Joined: Oct 2007
Posts: 243
Likes: 2
From:
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

tomato - love your v-rod setup! Would you care to provide a detail description of what is required to upgrade to v-rod setup.
I'd imagine that you need at least the following:

1. V-rod front forks
2. V-rod front discs
3. V-rod front calipers

What model V-rod did you use as a donor bike? What modifications do you need in order to fit the above? I would appreciate any detailed info?

Have you considered the Fat Bob twin setup?
 
Reply
Old Mar 30, 2008 | 10:08 AM
  #8  
FastHarley's Avatar
FastHarley
Former Sponsor
Joined: Apr 2007
Posts: 5,360
Likes: 453
From: Davie, FL
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

First of all the internal valving is different on the V-Rod than your bike. The V-rod is also 2" shorter. Once you completely set up your bike you also need to buy a 2" (approximate) shock. I have all of the parts needed to do this job at HD. Will pick them up tomorrow & get to work. Once we figure it out, we will put one on Jay Risk's bike for testing. Might even do Mudd's bike also. Jay wants Brembo's. tomato, good job and rims looks nice. Always been a sucker for the red ones.

Ps the rotors are 300 millimeter = 11.811 023 622 inch or 0.15551" (Radis) (Around 5/32") larger than your stock rotors. I do not think it would work as I have a set of 6/differential PM's and they are very tight against the top of the 11.5" rotor. $499 X 2 = alot of investment to sell on e-Bay
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom

 Verdad Gallardo
story-1

6 Weirdest Harley-Davidsons Ever Sold to the Public

 Verdad Gallardo
story-2

7 Times Harley-Davidson Chucked Tradition Out the Window

 Verdad Gallardo
story-3

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-4

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-5

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-6

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

 Verdad Gallardo
story-7

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

 Verdad Gallardo
story-8

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-9

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
Old Mar 30, 2008 | 11:47 PM
  #9  
vladt's Avatar
vladt
Thread Starter
|
Cruiser
Joined: Oct 2007
Posts: 243
Likes: 2
From:
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

FastHarley - Please keep us posted on your progress. Would love to know the exact details/problems of the conversion.
Have you considered the Fab Bob twin setup?
 
Reply
Old Mar 31, 2008 | 08:42 AM
  #10  
FastHarley's Avatar
FastHarley
Former Sponsor
Joined: Apr 2007
Posts: 5,360
Likes: 453
From: Davie, FL
Default RE: PM 6 piston calipers on 08 Street Bob - No go!!!

Monday update

Others have tried it and the only way that works is if you use new trees off of a FB. The calipers do not line up with the rotors, understandability. Do a search or "talk" with the member who posted photos on this forum. This approach is not the one I wanted to take.

My goal is to use your mid-glide (stock) trees, a 2X hub like the one found on your spoked wheel, add a 300 mm rotor and add caliper(s). Of course you need lowers w/2X caliper mounting points. When/if we come up with a viable solution, I shall post only after it has been extensively road tested for reliability and safety. This must be a cost effective modification only.

I do not own a 06 & above bike to personally test it on. I have tried to buy a complete 49mm front end to put on my 05 Dyna for testing only. The member here who had the complete front end has not contacted be back yet with repleted attempts on my side. I will pick up the brand new stuff from HD today or tomorrow. Our first step.

Jay Risk has been working with me and has professed to give a truthful and honest evaluation for you guys. He owns this type of bike.
 
Reply



All times are GMT -5. The time now is 05:17 AM.

story-0
Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom

Slideshow: Killer Custom's latest build relies on styling changes rather than performance upgrades, giving the cruiser an entirely different personality.

By Verdad Gallardo | 2026-06-03 18:28:05


VIEW MORE
story-1
6 Weirdest Harley-Davidsons Ever Sold to the Public

Slideshow: From military-inspired singles to scooters and three-wheel utility vehicles, these Harleys took the company far outside its comfort zone.

By Verdad Gallardo | 2026-06-02 18:34:10


VIEW MORE
story-2
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-3
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-4
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-5
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-6
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-7
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-8
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-9
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