<PAGE>   1

 
                                                      Registration No. 33-39113

     As filed with the Securities and Exchange Commission on June 29, 1994
________________________________________________________________________________

                        POST-EFFECTIVE AMENDMENT NO. 1
                                      TO
                                   FORM S-8

                            REGISTRATION STATEMENT
                                     UNDER
                          THE SECURITIES ACT OF 1933
                              __________________
                                       
                        BRIGGS & STRATTON CORPORATION*
            (Exact name of registrant as specified in its charter)

             WISCONSIN                                      39-0182330
  (State or other jurisdiction of                        (I.R.S. Employer
  incorporation or organization)                        Identification No.)

       12301 W. Wirth Street
        Wauwatosa, Wisconsin                                            53222
(Address of Principal Executive Offices)                              (ZIP Code)
                              __________________
                                       
                       THE BRIGGS & STRATTON CORPORATION
                             STOCK INCENTIVE PLAN
                           (Full title of the plan)
                              ___________________
                                                            Copy to:
     THOMAS R. SAVAGE, ESQ.                           THOMAS W. O'BRIEN, ESQ.
        General Counsel                                    Quarles & Brady
  BRIGGS & STRATTON CORPORATION                      411 East Wisconsin Avenue
      12301 W. Wirth Street                          Milwaukee, Wisconsin 53202
   Wauwatosa, Wisconsin  53222

                    (Name and address of agent for service)

                                (414) 259-5333
         (Telephone number, including area code, of agent for service)
                                       
________________________________

* The Registrant, Briggs & Stratton Corporation, a Wisconsin corporation, 
successor issuer to Briggs & Stratton Corporation, a Delaware corporation 
("Briggs & Stratton Delaware"), pursuant to a merger for the purpose of 
changing Briggs & Stratton Delaware's state of incorporation from Delaware to 
Wisconsin, hereby adopts as its own, pursuant to Rule 414(d) under the 
Securities Act of 1933, Briggs & Stratton Delaware's Registration Statement
on Form S-8, File No. 33-39113, and any amendments thereto, for all purposes of
the Securities Act of 1933 and the Securities Exchange Act of 1934.

        

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                                    PART I
                                       
             INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

        Information specified in Part I of Form S-8 (Items 1 and 2) will be
sent or given to Plan participants as specified by Rule 428(b)(1) under the
Securities Act of 1933.

                                    PART II

              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

        The following documents filed by Briggs & Stratton Corporation, a
Delaware corporation ("Briggs & Stratton Delaware") (Commission File No.
1-1370), or Briggs & Stratton Corporation, a Wisconsin corporation (the
"Registrant") (Commission File No. 1-1370), successor issuer to Briggs &
Stratton Delaware in a Delaware-to-Wisconsin change of domicile merger
effective at 5:00 p.m. on October 31, 1992, with the Securities and Exchange
Commission (the "Commission") pursuant to Section 13 of the Securities Exchange
Act of 1934 (the "1934 Act") are incorporated herein by reference:

         (a)     The Registrant's Annual Report on Form 10-K for the
                 fiscal year ended June 27, 1993;

         (b)     The Registrant's quarterly reports on Form 10-Q for the
                 quarterly periods ended September 26, 1993, December 26, 1993,
                 and March 27, 1994; 

         (c)     The Registrant's Current Report on Form 8-K dated May 18,
                 1994; and

         (d)     The description of the Registrant's Common Stock
                 contained in the Registrant's Registration Statement on Form
                 8-B, dated October 12, 1992, and filed with the Commission on
                 October 14, 1992, including any amendment or report filed for
                 the purpose of updating such description.

        All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the 1934 Act, prior to the filing of a
post-effective amendment which indicates that all securities offered hereby
have been sold or which deregisters all securities then remaining unsold, shall
be deemed to be incorporated by reference herein and to be a part hereof from
the date of the filing of such documents.

        Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded
for purposes hereof to the extent that a statement contained herein or in any
other subsequently filed document which also is or is deemed to be incorporated
by reference herein modifies or supersedes such statement.  Any statement so
modified or superseded shall not be deemed, except as so modified or
superseded, to constitute a part hereof.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not applicable.  See Item 3(d) above.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not applicable.


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ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

        The Registrant is incorporated under the Wisconsin Business Corporation
Law ("WBCL").  Under Section 180.0851(1) of the WBCL, the Registrant is
required to indemnify a director or officer, to the extent such person is
successful on the merits or otherwise in the defense of a proceeding, for all
reasonable expenses incurred in the proceeding if such person was a party
because he or she was a director or officer of the Registrant.  In all other
cases, the Registrant is required by Section 180.0851(2) of the WBCL to
indemnify a director or officer against liability incurred in a proceeding to
which such person was a party because he or she was an officer or director of
the Registrant, unless it is determined that he or she breached or failed to
perform a duty owed to the Registrant and the breach or failure to perform
constitutes:  (i) a willful failure to deal fairly with the Registrant or its
shareholders in connection with a matter in which the director or officer has a
material conflict of interest; (ii) a violation of criminal law, unless the
director or officer had reasonable cause to believe his or her conduct was
lawful or no reasonable cause to believe his or her conduct was unlawful; (iii)
a transaction from which the director or officer derived an improper personal
profit; or (iv) willful misconduct.  Section 180.0858(1) of the WBCL provides
that, subject to certain limitations, the mandatory indemnification provisions
do not preclude any additional right to indemnification or allowance of
expenses that a director or officer may have under the Registrant's articles of
incorporation, bylaws, a written agreement or a resolution of the Board of
Directors or shareholders.

        Section 180.0859 of the WBCL provides that it is the public policy of
the State of Wisconsin to require or permit indemnification, allowance of
expenses and insurance to the extent required or permitted under Sections
180.0850 to 180.0858 of the WBCL for any liability incurred in connection with
a proceeding involving a federal or state statute, rule or regulation
regulating the offer, sale or purchase of securities.

        Section 180.0828 of the WBCL provides that, with certain exceptions, a
director is not liable to a corporation, its shareholders, or any person
asserting rights on behalf of the corporation or its shareholders, for damages,
settlements, fees, fines, penalties or other monetary liabilities arising from
a breach of, or failure to perform, any duty resulting solely from his or her
status as a director, unless the person asserting liability proves that the
breach or failure to perform constitutes any of the four exceptions to
mandatory indemnification under Section 180.0851(2) referred to above.

        Under Section 180.0833 of the WBCL, directors of the Registrant against
whom claims are asserted with respect to the declaration of an improper
dividend or other distribution to shareholders to which they assented are
entitled to contribution from other directors who assented to such distribution
and from shareholders who knowingly accepted the improper distribution, as
provided therein.

        Article VIII of the Registrant's Bylaws contains provisions that
generally parallel the indemnification provisions of the WBCL and cover certain
procedural matters not dealt with in the WBCL.  

        Directors and officers of the Registrant are covered by directors' and
officers' liability insurance under which they are insured (subject to certain
exceptions and limitations specified in the policy) against expenses and
liabilities arising out of proceedings to which they are parties by reason of
being or having been directors or officers.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.


                                       
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<PAGE>   4

ITEM 8.  EXHIBITS.

        See Exhibit Index following Signatures page in this Registration
Statement, which Exhibit Index is incorporated herein by reference.

ITEM 9.  UNDERTAKINGS.

         (a)     The undersigned Registrant hereby undertakes:

                 (1)      To file, during any period in which offers or sales 
                          are being made, a post-effective amendment to this 
                          Registration Statement:

                          (i)     To include any prospectus required by 
                                  section 10(a)(3) of the Securities Act of 
                                  1933;

                          (ii)    To reflect in the prospectus any facts or 
                                  events arising after the effective date
                                  of the Registration Statement (or the most
                                  recent post-effective amendment thereof)
                                  which, individually or in the aggregate,
                                  represent a fundamental change in the
                                  information set forth in the Registration
                                  Statement;

                          (iii)   To include any material information with
                                  respect to the plan of distribution not
                                  previously disclosed in the Registration
                                  Statement or any material change to such
                                  information in the Registration Statement;

        Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
apply if the information required to be included in a post-effective amendment
by those paragraphs is contained in periodic reports filed by the Registrant
pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934
that are incorporated by reference in the Registration Statement.

        (2)      That, for the purpose of determining any liability under the
Securities Act of 1933, each such post-effective amendment shall be deemed to
be a new registration statement relating to the securities offered therein, and
the offering of such securities at that time shall be deemed to be the initial
bona fide offering thereof.

        (3)      To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

        (b)     The undersigned Registrant hereby undertakes that, for purposes
of determining any liability under the Securities Act of 1933, each filing of
the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of
the Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
Registration Statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

        (h)     Reference is made to the indemnification provisions referred to
in Item 6 of this Registration Statement.

        Insofar as indemnification for liabilities arising under the Securities
Act of 1933 may be permitted to directors, officers and controlling persons of
the Registrant pursuant to the foregoing provisions, or otherwise,





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<PAGE>   5

the Registrant has been advised that in the opinion of the Securities
and Exchange Commission such indemnification is against public policy as
expressed in the Act and is, therefore, unenforceable.  In the event that a
claim for indemnification against such liabilities (other than the payment by
the Registrant of expenses incurred or paid by a director, officer or
controlling person of the Registrant in the successful defense of any action,
suit or proceeding) is asserted by such director, officer or controlling person
in connection with the securities being registered, the Registrant will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the Act and
will be governed by the final adjudication of such issue.

















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<PAGE>   6

                                  SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
Amendment to the Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Milwaukee, State of
Wisconsin, on June 28, 1994.

                                BRIGGS & STRATTON CORPORATION
                                (Registrant)


                                By:  /s/FREDERICK P. STRATTON, JR. 
                                     Frederick P. Stratton, Jr.
                                Chairman, President, and Chief Executive Officer


                             ____________________



        Pursuant to the requirements of the Securities Act of 1933, this
Amendment to the Registration Statement has been signed by the following
persons in the capacities and on the date indicated.*


SIGNATURE                                          TITLE

/s/FREDERICK P. STRATTON, JR.          Chairman, President
Frederick P. Stratton, Jr.             and Chief Executive Officer and Director
                                       (Principal Executive Officer of the 
                                        Registrant)

/s/ROBERT H. ELDRIDGE            x     Secretary-Treasurer and Director
Robert H. Eldridge                     (Principal Financial Officer)

/s/JAMES E. BRENN                x     Vice President and Controller
James E. Brenn                         (Principal Accounting Officer)

/s/MICHAEL E. BATTEN             x     Director
Michael E. Batten

/s/PETER A. GEORGESCU            x     Director
Peter A. Georgescu

/s/SHELDON B. LUBAR              x     Director
Sheldon B. Lubar

/s/RICHARD E. MARCEAU            x     Director
Richard E. Marceau

/s/JOHN L. MURRAY                x     Director
John L. Murray




                                      S-1




<PAGE>   7

                                       Director
Clarence B. Rogers, Jr.

/s/ELWIN J. ZARWELL              x     Director
Elwin J. Zarwell

______________________

                 * Each of these signatures is affixed as of June 28, 1994.

                 x By:/s/FREDERICK P. STRATTON, JR.    
                      Frederick P. Stratton, Jr., as Attorney-in-Fact, pursuant 
                      to Power of Attorney contained in the Registration 
                      Statement.













                                      S-2


<PAGE>   8
                                       
                         BRIGGS & STRATTON CORPORATION
                              (THE "REGISTRANT")
   (SUCCESSOR TO BRIGGS & STRATTON CORPORATION, COMMISSION FILE NO. 1-1370)

                                 EXHIBIT INDEX
                                      TO
                        FORM S-8 REGISTRATION STATEMENT
                 (AS AMENDED BY POST-EFFECTIVE AMENDMENT NO.1)


<TABLE>
<CAPTION>
EXHIBIT                                                INCORPORATED HEREIN                 FILED              SEQUENTIAL
NUMBER           DESCRIPTION                           BY REFERENCE TO                    HEREWITH             PAGE NO.
<S>              <C>                                   <C>                                <C>                 <C>
4.1              Articles of Incorporation             Exhibit 3.1 to the Registrant's
                 of the Registrant                     Form 8-B dated October 12,
                                                       1992 (the "Form 8-B")

4.2              Bylaws of the Registrant              Exhibit 3.2 to the Form 8-B

4.3              Rights Agreement dated as             Exhibit 1 to Briggs & Stratton
                 of December 20, 1989, between         Corporation's Current Report
                 Briggs & Stratton Corporation         on Form 8-K dated December 20,
                 and First Wisconsin Trust             1989
                 Company, which includes the
                 form of Right Certificate as
                 Exhibit A and the Summary of
                 Rights to Purchase Common
                 Shares as Exhibit B

5                Opinion of Counsel                                                          X

23.1             Consent of Arthur Andersen & Co.      Exhibit 23 to the Registrant's
                                                       Annual Report on Form 10-K for
                                                       the fiscal year ended June 27,
                                                       1993

23.2             Consent of Counsel                                                         Contained in
                                                                                            Opinion filed
                                                                                            as Exhibit 5

24               Powers of Attorney                    Signatures Page
                                                       to original
                                                       Registration Statement

99.1             The Briggs & Stratton                 Exhibit A to Briggs & Stratton
                 Corporation Stock Incentive           Corporation's Proxy 
                 Plan                                  Statement dated September 9, 
                                                       1993 for its Annual Meeting 
                                                       of Stockholders on October 20,
                                                       1993

99.2             Agreement and Plan of                 Exhibit 1 to the Form 8-B
                 Merger by and between the 
                 Registrant and Briggs & Stratton
                 Corporation, dated as of
                 October 1, 1992

</TABLE>




                                     EI-1





<PAGE>   1


                                                                       Exhibit 5



                                                                  June 28, 1994




Briggs & Stratton Corporation
12301 W. Wirth Street
Wauwatosa, Wisconsin  53222

Gentlemen:

        We are providing this opinion in connection with Post-Effective
Amendment No. 1 to the Registration Statement of Briggs & Stratton Corporation,
a Delaware corporation ("Briggs & Stratton"), on Form S-8, File No. 33-39113
(the "Registration Statement"), filed on February 21, 1991 under the Securities
Act of 1933, as amended (the "Act"), with respect to the proposed sale by Briggs
& Stratton of up to 400,000 shares of common stock, par value $3.00 per share,
of Briggs & Stratton ("Briggs & Stratton Common Stock") upon the exercise of
options granted under the Briggs & Stratton Corporation Stock Incentive Plan
(the "Plan"). 

        Briggs & Stratton Corporation, a Wisconsin corporation (the "Company"),
was created as a wholly-owned subsidiary of Briggs & Stratton in connection with
the Agreement and Plan of Merger, dated as of October 1, 1992, between Briggs &
Stratton and the Company (the "Merger Agreement"), pursuant to which Briggs &
Stratton was merged with and into the Company (the "Merger") effective at 5:00
p.m., Milwaukee, Wisconsin time on October 31, 1992 (the "Effective Date"), for
the purpose of changing its state of incorporation from Delaware to
 Wisconsin. 
The Company is the surviving corporation in the Merger.  At the Effective Date:
(i) each outstanding share of Briggs & Stratton Common Stock was automatically
converted into one (1) share of common stock, par value $0.01 per share, of the
Company ("Common Stock"); (ii) each outstanding stock option to purchase shares
of Briggs & Stratton Common Stock (an "Option") granted by Briggs & Stratton
pursuant to the Plan was automatically converted into a stock option to
purchase, upon the same terms and conditions, the number of shares of Common
Stock which is equal to the number of shares of Briggs & Stratton Common Stock
which the holder thereof would have received had such holder exercised the
Option in full immediately prior to the Effective Date (whether or not such
option was then exercisable); and (iii) the Plan was assumed by, and continues
to be the Plan of, the Company.  The shares of Common Stock of the Company which
remain available for issuance under the Plan as so assumed by the Company
pursuant to the Merger, whether subject to outstanding Options so assumed or
available for the grant of further options thereunder, are herein referred to as
the "Shares."  Post-Effective Amendment No. 1 to the Registration Statement is
being filed by the Company, as the successor issuer to Briggs & Stratton, to
adopt the Registration Statement as its own for all purposes of the Act and the
Securities Exchange Act of 1934 in accordance with Rule 414 promulgated under
the Act. 

        We have examined (i) the Registration Statement, as amended by
Post-Effective Amendment No. 1, (ii) the Company's Articles of Incorporation and
Bylaws, (iii) the Plan, as assumed by the Company pursuant to the Merger, (iv)
the Merger Agreement; (v) the corporate proceedings relating to the adoption of
the Plan, the







<PAGE>   2

Briggs & Stratton Corporation
June 28, 1994
Page 2





issuance of the Shares, the organization of the Company and the Merger,
and (vi) such other documents and records as we have deemed necessary in order
to render this opinion.  In rendering this opinion, we have relied as to certain
factual matters on certificates of officers of the Company and of state
officials.

         Based upon the foregoing, it is our opinion that:

         1.      The Company is a corporation duly incorporated and
                 validly existing under the laws of the State of Wisconsin. 

         2.      The Shares, when issued and paid for as contemplated by
                 the Registration Statement, as amended, and the Plan, will be
                 validly issued, fully paid and non-assessable by the Company,
                 subject to the personal liability which may be imposed on
                 shareholders by Section 180.0622(2)(b) of the Wisconsin
                 Business Corporation Law, as judicially interpreted, for debts
                 owing to employees for services performed, but not exceeding
                 six months service in any one case.  Although Section
                 180.0622(2)(b) provides that such personal liability of
                 shareholders shall be "to an amount equal to the par value of
                 shares owned by them respectively, and to the consideration for
                 which their shares without par value was issued," the Wisconsin
                 Supreme Court, by a split decision without a written opinion,
                 has affirmed a judgment holding shareholders of a corporation
                 liable under the substantially identical predecessor statute in
                 effect prior to January 1, 1991 (Section 180.40(6)) for unpaid
                 employee wages to an amount equal to the consideration for
                 which their par value shares were issued rather than the
                 shares' lower stated par value.  Local 257 of Hotel and
                 Restaurant Employees and Bartenders International Union v.
                 Wilson Street East Dinner Playhouse, Inc., 126 Wis. 2d 284, 375
                 N.W.2d 664 (1985) (affirming the 1983 decision of the Circuit
                 Court for Dane County, Wisconsin, in Case No. 82-CV-0023).  

        We consent to the filing of this opinion as an Exhibit to the
Registration Statement.  In giving this consent, we do not admit that we are
"experts" within the meaning of Section 11 of the Act, or that we come within
the category of persons whose consent is required by Section 7 of the Act.  Mr.
Elwin J. Zarwell, a partner in our firm, is a director of the Company.  

                                                   Very truly yours,




                                                   QUARLES & BRADY