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                                                                    EXHIBIT 10.2

                            STOCK PURCHASE AGREEMENT

      This stock purchase agreement (the "Agreement") is made and entered into
as of January 6, 2006 by and between Slammer Partners L.P., a Texas limited
partnership ("Slammer"), Tim D. Edmondson ("Edmondson"), and Xponential, Inc., a
Delaware corporation ("Buyer"). Slammer, Edmondson and Buyer are hereinafter
sometimes referred to individually as a "party" and collectively as the
"parties."

      WHEREAS, Slammer is the record and beneficial owner of 190,000 shares of
common stock, $0.01 par value (the "Common Stock"), of American IronHorse
Motorcycle Company, Inc., a Texas corporation (the "Company"), of which 45,000
shares are pledged to secure indebtedness owed to the Company and 145,000 shares
are free and clear of any obligations or encumbrances; and

      WHEREAS, Tim Edmondson is the general partner of Slammer; and

      WHEREAS, Slammer desires to sell to Buyer, and Buyer desires to purchase
from Slammer, 190,000 shares of Common Stock (the "Shares") on the terms herein
described;

      NOW, THEREFORE, in consideration of the mutual agreements contained herein
and other good and valuable consideration, the receipt and sufficiency of which
is acknowledged by the parties, the parties agree as follows:

      1. SALE OF SHARES. Subject to the terms and conditions of this Agreement,
Slammer shall sell to Buyer, and Buyer shall purchase from Slammer, the Shares.

      2. CONSIDERATION. The consideration to be paid by Buyer to Slammer for the
Shares is $1,615,000, or $8.50 per Share (the "Consideration"), payable as
follows:

            (a) payment by Buyer to the Company of $147,055.58, which represents
the outstanding principal and accrued interest, on that certain promissory note
payable by Tim D. Edmondson and Seller to the Company dated February 1, 2004 in
the original principal amount of $133,384.22 (the "Prior Note") which will cause
the Company to release the certificate evidencing the pledged Shares to Buyer
(Edmondson and Slammer hereby direct Seller to make such payment directly to the
Company);

            (b) payment of $500,000 by check to Slammer; and

            (c) the balance by the execution and delivery of an unsecured
promissory note in the amount of the balance of the Consideration payable in
thirty six (36) equal monthly installments of principal plus accrued interest,
with the first payment due and payable on February 6, 2006 and continuing on the
same date thereafter until paid in full (the "Note").

            In the event of the closing on or before December 31, 2006 of a firm
commitment underwritten public offering pursuant to an effective registration
statement under the Securities Act of 1933, as amended (the "Securities Act"),
covering

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the offering and sale of the Company's common stock for the account of the
Company in which the aggregate gross proceeds received by the Company equals or
exceeds $30,000,000 and in which the price per share is equal to or greater than
$15.00 (based on the current number of shares of common stock outstanding, as
adjusted for any subsequent stock splits) the following will occur within thirty
(30) days following the closing of such an offering (i) the Note will become due
and payable in full, and (ii) Buyer will pay to Seller in cash an additional
$2.00 per share for the Shares ($380,000). Upon the closing of such an offering,
payment in full of the Note and additional $2.00 per Share consideration, the
parties shall have no further rights or obligations hereunder.

      3. CLOSING. In the absence of contrary agreement between the parties, the
sale shall be closed (the "Closing") at the offices of Holland, Johns, Schwartz
& Penny, L.L.P., 306 West Seventh Street, Suite 500, Fort Worth, Texas 76102, at
a mutually agreeable time but in no event later than January 6, 2006.

      4. DELIVERY AT CLOSING.

            (a) At the Closing Slammer will deliver to Buyer the certificates
and other instruments evidencing the Shares being purchased by Buyer duly
endorsed in blank or accompanied by a stock power executed in blank in proper
form for transfer.

            (b) At the Closing, Buyer will deliver:

                  (1) to the Company a check in the amount of $147,055.58
representing payment in full of the Prior Note;

                  (2) to Slammer a check in the amount of $500,000, representing
the portion of the Consideration due and payable at the Closing; and

            (c) to Slammer the Note.

      5. SLAMMER'S REPRESENTATIONS AND WARRANTIES. Slammer represents and
warrants to Buyer that the statements contained in this SECTION 5 are correct
and complete as of the date of this Agreement and will be correct and complete
as of the Closing (as though made then and as though the Closing date were
substituted for the date of this Agreement throughout this SECTION 5) with
respect to itself.

            (a) Slammer is duly organized, validly existing, and in good
standing under the laws of the jurisdiction of its formation.

            (b) Slammer has full power and authority to execute and deliver this
Agreement and to perform its obligations hereunder. This Agreement constitutes
the valid and legally binding obligation of Slammer, enforceable in accordance
with its terms and conditions. Slammer need not give any notice to, make any
filing with, or obtain any authorization, consent, or approval of any government
or governmental agency in order to consummate the transactions contemplated by
this Agreement. The execution, delivery and performance of this Agreement and
all other agreements contemplated hereby have been duly authorized by Slammer.

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            (c) Neither the execution and the delivery of this Agreement, nor
the consummation of the transactions contemplated hereby, will (i) violate any
constitution, statute, regulation, rule, injunction, judgment, order, decree,
ruling, charge, or other restriction of any government, governmental agency, or
court to which Slammer is subject or any provision of its charter, bylaws, or
other governing documents, (ii) conflict with, result in a breach of, constitute
a default under, result in the acceleration of, create in either party the right
to accelerate, terminate, modify, or cancel, or require any notice under any
agreement, contract, lease, license, instrument, or other arrangement to which
Slammer is a party or by which it is bound or to which any of its assets is
subject, or (iii) result in the imposition or creation of a lien upon or with
respect to the Shares.

            (d) Slammer holds of record and owns beneficially the Shares free
and clear of any restrictions on transfer (other than restrictions under the
Securities Act and state securities laws), taxes, liens, options, warrants,
purchase rights, contracts, commitments, equities, claims, and demands. Slammer
is not a party to any option, warrant, purchase right, or other contract or
commitment relating to the Shares (other than this Agreement). Slammer is not a
party to any voting trust, proxy, or other agreement or understanding with
respect to the Shares.

            (e) The provisions of this SECTION 5 shall survive the Closing.

      6. BUYER'S REPRESENTATIONS AND WARRANTIES. Buyer represents and warrants
to Slammer that the statements contained in this SECTION 6 are correct and
complete as of the date of this Agreement and will be correct and complete as of
the Closing (as though made then and as though the Closing date were substituted
for the date of this Agreement throughout this SECTION 6) with respect to
itself.

            (a) Buyer has full power and authority (including full corporate
power and authority) to execute and deliver this Agreement and to perform its
obligations hereunder. This Agreement constitutes the valid and legally binding
obligation of Buyer, enforceable in accordance with its terms and conditions.
Buyer need not give any notice to, make any filing with, or obtain any
authorization, consent, or approval of any government or governmental agency in
order to consummate the transactions contemplated by this Agreement.

            (b) Neither the execution and the delivery of this Agreement, nor
the consummation of the transactions contemplated hereby, will (i) violate any
constitution, statute, regulation, rule, injunction, judgment, order, decree,
ruling, charge, or other restriction of any government, governmental agency, or
court to which Buyer is subject, (ii) conflict with, result in a breach of,
constitute a default under, result in the acceleration of, create in either
party the right to accelerate, terminate, modify, or cancel, or require any
notice under any agreement, contract, lease, license, instrument, or other
arrangement to which Buyer is a party or by which he is bound or to which any of
his assets is subject, or (iii) result in the imposition or creation of a lien
upon or with respect to the Shares.

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            (c) The Shares will be acquired for investment for Buyer's own
account, not as a nominee or agent, and not with a view to the resale or
distribution of any part thereof, and Buyer has no present intention of selling,
granting any participation in, or otherwise distributing the same, except in
compliance with applicable federal and state securities laws. Buyer does not
have any contract, undertaking, agreement or arrangement with any person to
sell, transfer or grant participations to such person with respect to any of the
Shares.

            (d) The Shares are not being registered under the Securities Act on
the ground that the sale provided for in this Agreement is exempt from
registration under applicable state and federal securities laws.

            (e) Buyer has received all the information Buyer considers necessary
or appropriate for deciding whether to purchase the Shares; provided that the
information provided by Slammer to Buyer does not contain any untrue statement
of any material fact or omit to state any material fact necessary in order to
make the statements therein, in the light of the circumstances under which they
are made, not misleading.

            (f) Buyer is experienced in evaluating and investing in securities
of companies similar to the Company, is represented by legal and/or investment
advisory counsel with regard to this Agreement or has voluntarily elected to
forego such counsel, can bear the economic risk of its investment in the Shares,
and has such knowledge and experience in financial and business matters that it
is capable of evaluating the merits and risks of an investment in the Shares.

            (g) The Shares may not be sold, transferred, or otherwise disposed
of without registration under the Securities Act or an exemption therefrom, and,
in the absence of an effective registration statement covering the Shares or an
available exemption from registration under the Securities Act, the Shares must
be held indefinitely.

            (h) The certificate(s) evidencing the Shares will be endorsed with
the legend set forth below:

      "THE SHARES OF STOCK REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
      RESTRICTIONS ON TRANSFER. THESE SHARES HAVE NOT BEEN REGISTERED UNDER THE
      SECURITIES ACT OF 1933 OR UNDER ANY APPLICABLE STATE LAW. THEY MAY NOT BE
      OFFERED FOR SALE, SOLD, TRANSFERRED OR PLEDGED WITHOUT EITHER (1)
      REGISTRATION UNDER THE SECURITIES ACT OF 1933 AND APPLICABLE STATE LAW, OR
      (2) AN OPINION OF LEGAL COUNSEL SATISFACTORY TO THE CORPORATION THAT THESE
      SHARES ARE EXEMPT FROM SUCH REGISTRATION."

            (i) The provisions of this SECTION 6 shall survive the Closing.

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      7. WAIVER OF CONFLICT.

            (a) Slammer and Buyer each acknowledge that Margaret E. Holland and
the law firm of Holland, Johns, Schwartz & Penny, L.L.P. have represented
Slammer and Edmondson since approximately April 1999, Buyer since approximately
March 2001, and the Company since approximately March 1998. By the execution of
this Agreement, Slammer and Buyer each (i) waive for itself/himself and those
who could claim by, through, or under it/him any conflicts of interest or
potential conflict of interest that might arise out of such prior
representation, (ii) acknowledge that it/he has been apprised of such potential
conflict of interest, and (iii) acknowledge that it/he has been fully informed
of the legal implications of this waiver of conflict of interest and has been
advised to retain separate legal counsel to advise it/him on this matter.

            (b) The parties, by signing this Agreement, agree as follows:

                  (1) that the parties acknowledge the disclosure of the
potential and actual conflicts of interest described herein as they relate to
Margaret E. Holland and Holland, Johns, Schwartz & Penny, L.L.P;

                  (2) that the parties agree to waive any potential or actual
conflicts of interest associated with the contemplated legal work by Holland,
Johns, Schwartz & Penny, L.L.P. in connection with the representation in
connection with this Agreement;

                  (3) that, as to arbitration and litigation concerning this
Agreement, Slammer will not seek to disqualify Buyer's legal counsel from its
representation, or support such disqualification, in connection with the
transaction contemplated by this Agreement; and

                  (4) that the parties are fully informed regarding the legal
implications of this waiver of conflicts of interest and have the right, which
Holland, Johns, Schwartz & Penny, L.L.P. encourages, to seek and obtain advice
of independent legal counsel concerning the law and the implications of this
waiver request.

      8. SEVERABILITY. To the extent that any provision herein is inconsistent
with or in violation of any applicable law, rule or regulation, such provision
shall be deemed modified so as to comply with such applicable law, rule or
regulation, and shall not otherwise affect any other provisions of this
Agreement. Any provision of this Agreement that is invalid or unenforceable in
any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such invalidity or unenforceability without rendering invalid or unenforceable
the remaining provisions of this Agreement or affecting the validity or
enforceability of that provision or of any other provisions of this Agreement in
any other jurisdiction.

      9. GOVERNING LAW. This Agreement shall be construed in accordance with the
laws of the State of Texas.

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      10. FURTHER ACTIONS. At any time and from time to time, each party agrees,
without further consideration, to take such actions and to execute and deliver
such documents as may be reasonably necessary to effect the purposes of this
Agreement.

      11. COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

      12. ADVICE OF COUNSEL; VOLUNTARY AGREEMENT. Each of the parties agrees and
represents that such party has been represented by each party's own separate
counsel with regard to the execution of this Agreement or that, if acting
without counsel, such party has had adequate opportunity and understands the
importance to such party's interest of obtaining the advice of such party's own
separate counsel prior to the execution of this Agreement and has knowingly and
freely waived the right to obtain advice of such party's own separate counsel.
Each party has fully read and understands this Agreement. This Agreement is the
knowing and voluntary agreement of each of the parties.

      13. ENTIRE AGREEMENT. This Agreement and the instruments called for by
this Agreement constitute the whole agreement of the parties and supersedes any
commitment, agreement, memorandum or understanding previously made by the
parties, or any of them, with respect to the subject matter of this Agreement.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first above written.

SLAMMER:                                  SLAMMER PARTNERS L.P.

                                          By: /s/ Tim D. Edmondson
                                              ----------------------------------
                                              Tim Edmondson, General Partner

                                          P.O. Box 78
                                          Argyle, Texas 76226

EDMONDSON:                                /s/ Tim D. Edmondson
                                              ----------------------------------
                                              Tim D. Edmondson

                                          P.O. Box 78
                                          Argyle, Texas 76226

BUYER:                                    XPONENTIAL, INC.

                                          By: /s/ Dwayne A, Moyers
                                              ----------------------------------
                                          Its: Chairman & CEO
                                              6400 Atlantic Boulevard, Suite 190
                                              Norcross, Georgia  30071

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                                 PROMISSORY NOTE

$967,944.42                  Fort Worth, Texas                   January 6, 2006

      FOR VALUE RECEIVED, the undersigned, Xponential, Inc. ("Maker"), with its
principal offices located at 6400 Atlantic Boulevard, Suite 190, Norcross,
Georgia 30071, promises to pay to the order of Slammer Partners, L.P. ("Payee")
at its offices located at P. O. Box 78, Argyle, Texas 76226, Denton County,
Texas, the sum of NINE HUNDRED SIXTY SEVEN THOUSAND NINE HUNDRED FORTY-FOUR AND
42/100 DOLLARS ($967,944.42) in legal and lawful money of the United States of
America, together with interest thereon from the date hereof until maturity at
the rate of seven and one-quarter percent (7.25%) per annum. All past due
principal and interest shall bear interest at ten percent (10%) per annum.

      No provision of this note shall require the payment or permit the
collection of interest in excess of the maximum lawful rate which Maker may
stipulate and agree to pay as determined by a court of competent jurisdiction.
If it is so determined that any excess interest is provided for herein, Maker
shall not be obligated to pay the amount of interest to the extent that it is in
excess of the amount permitted by law, and any excess interest paid shall be
credited as a payment on the principal balance or, if applicable, refunded to
Maker.

      Unless maturity is accelerated as provided below, this note is payable as
follows: principal and interest are due in thirty-six (36) monthly installments
of $29,998.08 each, payable on the sixth day of each and every calendar month,
beginning February 6, 2006 and continuing regularly thereafter until all
principal and all unpaid accrued interest has been paid in full.

      All payments received on this note shall be credited first to the
discharge of the interest accrued and the balance to the reduction of principal.

      Maker hereof reserves the right to prepay, prior to maturity, all or any
part of the principal of this note without penalty, and interest shall
immediately cease on any amount so prepaid. Any prepayment is to be applied
toward the payment of the principal installments last maturing upon this note,
that is, in the inverse order of maturity and without reducing the amount or
time of payment of the remaining obligatory installments.

      This note shall be governed by the laws of the State of Texas and all
applicable federal laws.

      It is expressly agreed that upon default in the punctual payment of this
note or any part thereof, principal or interest, as the same shall become due
and payable, the entire indebtedness evidenced hereby shall be matured, at the
option of the holder hereof.

      In the event this note, or any part hereof, is placed in the hands of an
attorney for collection or is collected through probate, bankruptcy, or other
judicial proceedings

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(including any proceedings, state or federal, for the relief of debtors), Maker
agrees to pay to the holder hereof a reasonable attorney's fee which in no event
shall be less than ten percent (10%) of the principal and interest then due
hereon.

      Maker and any sureties and endorsers of this note expressly waive all
notices, demands for payment, presentations for payment, notices of acceleration
and of intention to accelerate the maturity, protest and notice of protest, as
to this note, and as to each, every and all installments hereof, and each
consents that Payee or any other holder of this note may at any time, and from
time to time, upon request of or by agreement with Maker, extend the date of
maturity hereof or change the time or method of payments without notice to any
of the sureties or endorsers, who shall remain bound for the payment hereof.

      This principal and accrued interest is subject to acceleration as more
fully described in that certain Stock Purchase Agreement dated as of the date
hereof by and among Payee, Maker and Tim D. Edmondson.

                                        Xponential, Inc.

                                            By: /s/ Dwayne A, Moyers
                                                --------------------------------
                                                Chairman & CEO

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