Collection: 
            
          Crankcase & Bottom End - 1936-99
24 productsShop the range of aftermarket motorcycle engine products at Pro Class Custom Parts.
      
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               Exhaust System 2:1
- Breakout (2:1)
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               Exhaust System 2:2
 
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               Gauges - Bagger & Dresser
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               Speedo 3-3/8" Tank & Bar MT
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               Speedo 4.5" Tank Mt 1936-03
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 - Touring (FLH) 2024up Dual Seats
 - Vintage (1936-84) Dual Seats
 
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               Pillion Pads
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 - Softail Solo Seats 2018up
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 - Touring (FLH) 1991-2007 Solo Seats
 - Touring (FLH) 2008-2023 Solo Seats
 - Touring (FLH) 2024up Solo Seats
 - Vintage(1936-84) Solo Seats
 
 
          Suspension
        
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               FXR
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               Front Susp. Related
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               Front Suspension: 35 & 39mm
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               Front Suspension: 41mm
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               Front Suspension: 49mm
 - Rear Shocks Related - Universal
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               Rear Shocks: Dyna
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               Rear Shocks: FLH
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               Rear Shocks: HD Street
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               Rear Shocks: HD Trike
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               Rear Shocks: Indian & Victory
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               Rear Shocks: Metric
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               Rear Shocks: Softail
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               Rear Shocks: V-Rod
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               Rear Shocks: Vintage
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               Rear Shocks: XL'04up
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               Universal Suspension
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               XL'79-03
 
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          Tools & Supplies
        
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               General Workshop Equipment
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               Harley-Davidson Specific Tools
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               Indian & Victory Tools
 
          Transmission & Final Drive
        
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               Final Drive
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               Transmission - BT 4 spd era
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               Transmission - BT 5 spd era
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               Transmission - BT 6 spd era
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               Transmission - XL 4 spd era
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               Transmission - XL 5 spd era
 
          Windshields & Luggage
        
        
        
        
      
        
        
          Connecting Rod Race & Bushing Kit. Fits Big Twin 1941-1999.
        
        
          
  
          
          
          
            
        
        
  
    
      Regular price
      $577.99
  
  
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      $577.99
    
  
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Features & Benefits:-
* Includes 1 x Front Rod Race # SS34-4005
* Includes 2 x Rear Rod Race # SS34-4006
* Includes 2 x Wrist Pin Bush # SS34-4007
* Replaces OEM #’s 24356-36A 24345-36A & ...
        
        
        
  
        
       
      
        
        
          Crankcase Assembly with 3-1/2in. Bore – Black. Fits Big Twin 1992-1999.
        
        
          
  
          
          
          
            
        
        
  
    
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      $4,299.99
  
  
      Sale price
      $4,299.99
    
  
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Features & Benefits:-
* Wrinkle Black.
* Perfect for stock replacement & high performance applications.
* These crankcases offer some unique features. 
* Besides being machined for a crank...
        
        
        
  
        
       
      
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          Crankcase Assembly with 3-1/2in. Bore – Black. Fits Big Twin 1984-1991.
        
        
          
  
          
          
          
            
        
        
  
    
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      $4,299.99
  
  
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      $4,299.99
    
  
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Features & Benefits:-
* Wrinkle Black.
* Perfect for stock replacement & high performance applications
* These crankcases offer some unique features. 
* Besides being machined for a crank ...
        
        
        
  
        
       
      
        
        
          4-5/8in. 89ci Stroker Flywheel Assembly. Fits Evolution Big Twin 1984-1999.
        
        
          
  
          
          
          
            
        
        
  
    
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      $4,145.99
  
  
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      $4,145.99
    
  
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S&S has been making stock bore stroker kits since the early 1960s. Theyre still popular today due to the excellent power gains for the money, as well as the easy installation. Stock bore stro...
        
        
        
  
        
       
      
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          4-1/4in. Stroke Flywheel Assembly. Fits 80ci Big Twins from 1973-1984.
        
        
          
  
          
          
          
            
        
        
  
    
      Regular price
      $4,492.99
  
  
      Sale price
      $4,492.99
    
  
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Features & Benefits:-
* Can also be used to upgrade your 1200cc Engine 1973-1980 to 1340cc/80ci Engine.
Tech Tips:-
* Upgrading your 1200cc Engine 1973-1980 to 80ci/1340cc Engine  requires the...
        
        
        
  
        
       
      
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          4-1/4in. Stroke Flywheel Assembly. Fits Evolution Big Twin 1984-1999.
        
        
          
  
          
          
          
            
        
        
  
    
      Regular price
      $3,808.99
  
  
      Sale price
      $3,808.99
    
  
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Features & Benefits:-
* Stock Replacement.
* 1990-1999 models require purchase of pinion shaft conversion kit # SS33-4148.
Proudly Made in the USA by S&S Cycle !  
MFR PART No: 32-2239
ROL...
        
        
        
  
        
       
      
        
        
          Alternator Style Crankcase Assembly with Stock Bore – Natural. Fits Big Twin 1970-1984.
        
        
          
  
          
          
          
            
        
        
  
    
      Regular price
      $3,910.99
  
  
      Sale price
      $3,910.99
    
  
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Features & Benefits:-
* The S&S Super Stock alternator style crankcases are perfect for stock replacement & for high performance applications. 
* Pre-clearanced for strokes up to &...
        
        
        
  
        
       
      
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          Heavy Duty Connecting Rods. Fits Big Twin 1941-1981.
        
        
          
  
          
          
          
            
        
        
  
    
      Regular price
      $1,495.99
  
  
      Sale price
      $1,495.99
    
  
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Features & Benefits:-
* 7.440″ Rod Length.
* Sold as a Pair.
Tech Tips:-
* Torque crankpin nuts to H-D specs 180-210 ft/lbs for both OEM & S&S forged flywheels. 
* Greater torque will ...
        
        
        
  
        
       
      
        
        
          Heavy Duty Connecting Rods. Fits Evo 1984-1999
        
        
          
  
          
          
          
            
        
        
  
    
      Regular price
      $1,420.99
  
  
      Sale price
      $1,420.99
    
  
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Features & Benefits:-
* 7.440″ Rod Length.
* Sold as a Pair.
Tech Tips:-
* Torque crankpin nuts to H-D specs 180-210 ft/lbs for both OEM & S&S forged flywheels. 
* Greater torque will ...
        
        
        
  
        
       
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