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 Engine Crankcases

for Harley-Davidson & American Motorcycles

Please note:  No Returns. MSO (manufacturer's statement of origin) items are not returnable except for defect.

S&S Crankcase for 1970/84 Harley Davidson motorcycle.


S&S crankcase for 84/91 Harley-Davidson motorcycle


S&S Crankcase in natural finish for 92/99 HD


S&S Crankcase in Silver Finish for Twin Cam


S&S motorcycle engine crankcase for Twin Cam in Black finish.



For higher performance applications or just a replacement for a worn out engine. These casesare compatible with the stock primary, charging system and all other stock components.
Much stronger than stock crankcases in every aspect.
Includes bearings and installation hardware.
Clearanced for up to 5" strokes.

1970/1984 Cases: Clearanced for up to 38 amp stators

1984/1999 Cases: Relocated cam chest oil pick-up increases gear case scavenging and virtually eliminates oil carry-over at sustained high speeds. A ported breather passageway and a machined breather window. Crankcase breathing thru cases and heads.

1999/2006 Cases: Extra large front motor mount for increased strength. Large cam chest allows for up to .675" cam lift. Timken style sprocket shaft bearings. Includes S&S crankcase breather reed valve to eliminate oil carry over and scavenging problems

Made in the U.S.A.

S&S Crankcase Style (STOCK BORE) Finish Part # Price Add to Cart
1970/1984 Natural M60309 $1111.60
1984/1991 Natural M60310 $1111.60
1992/1999 Natural M60311 $1111.60
1999/2006 Twin Cam (except 2006 Dyna) Silver M60312 $1693.95
1999/2006 Twin Cam (except 2006 Dyna) Black M60313 $1693.91
engine crankcase for big twin motorcycles


Permanent mold castings used to manufacture crankcases give superior strength, closer tolerances and better aluminum to insert adhesion.
Pre-heated right and left case inserts with larger radiused ears removes vapor pockets & allows for superior aluminum flow, and iron to aluminum adhesion to eliminate possible insert movement.
Cylinder studs, Timken® main bearings and pinion race installed as well as line lapped to standard size.
Full complement cam bearing included.
Extra rib on the left front motor mount prevents motor mount breakage & adds rigidity to the case.
Solid dowel locating pins insure perfect alignment of case halves when assembled.
Blind case bolt & barrel stud holes eliminate the thin areas where holes normally intersect.
Alternator stator plug located .300" outboard eliminates thin area at left case race.
Rerouted oil passages eliminate weakness between lifter blocks & cylinders.
Includes chrome engine case bolt kit.
Includes Manufacturers Statement of Origin (shipped seperately for your protection).

Made in the U.S.A.

Part #: M60333 - Fits Shovelhead 1970/Later. Stock bore ... $998.09

Part#: M60348 - Fits Big Twin Evolution 1984/1991. Stock bore ... $998.09

Part#: M60351 - Fits Big Twin Evolution 1992/Later. Stock bore ... $998.09

fatso engine crankcase assy for twin cam top ends


As cast finish in 3.875" bore.
The Fatso motor is unique in that it allows you to have the benefits of a single cam Evo style lower end and use an OE cam top end.
Includes Manufacturer's Statement of Origin (shipped seperately for your protection).

Made in the U.S.A.

Part #: M60332 - Delkron Crankcase Assembly. Use with Twin Cam Top End ... $1,499.16

Chrome plated cylinder base / crankcase cover for Big Twin Harley-Davidson motorcycles.

Big Twin

Cylinder base / crankcase cover for sportster.


NEW! FLAT RATE SHIPPING:  $12.95 for 1 item or 100+ items! Don't see everything you need?  Call or write, we have it all.


Adds a show chrome look to the left side of your engine.
Easy to install.
Includes hardware.
Compliments either black or silver engine finishes.

Part #:M60616  - Chrome Plated. Fits Dyna 2006/Later, FLT & FLH 2007/Later (except CVO models & models equipped with 110 CI engines). Replaces HD# 32077-07 ... $48.95

Part #:M60615 - Chrome Plated. Fits Softail 2007/Later. Replaces HD# 32042-07 ... $48.95

Part#:M60614 - Chrome Plated. Fits Sportster 2004/Later
Replaces HD# 32729-07 ... $38.15



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Don't see what you need?  Contact us.  Chances are we have it.  We have thousands of parts that are not shown online.

PLEASE NOTE: We Do NOT Backorder. If your item is not in stock, you will be notified and given a refund.

FLAT RATE SHIPPING APPLIES IN CONTINTENTAL 48 UNITED STATES ONLY. AK, HI and APO/FPO will have additional shipping fees. We ship within the U.S.A. and to APO/FPO (military addresses; weight and size restrictions apply.). We do not accept foreign credit cards. Please see our CONTACT page for more information.

Prefer to call in your order to Steel Thunder? Call 603-237-8200.


Please note that all prices are subject to change.


Steel Thunder Custom Cycles

531 Bungy Road

Columbia, NH 03576

Copyright 2002-2017 Steel Thunder Custom Cycles©


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