This is a diversity wrongful death-products liability action filed by Roberta Ann McMurray against Deere & Company, Inc. McMurray is the executrix of the estate her husband, Dennis Ray McMurray (decedent), who was run over and killed by his tractor after “bypass starting” it. McMur-ray claims the tractor was defective because it could be bypass started while in gear, and because Deere failed to warn decedent of this fact. The case was tried to a jury which returned a verdict in Deere’s favor. After the district court denied her motion for a new trial, McMurray filed this appeal, asserting three claims of error regarding the jury instructions under Oklahoma law. We reverse and remand.
I
The pertinent facts are as follows. Decedent was killed after starting his tractor on his farm near Nowata, Oklahoma on October 9, 1983. The tractor is a 1977 John Deere 4640 agricultural model. It was first sold to another party in October 1977. The original dealer reacquired the tractor in October 1980 as a trade in, and then sold it to decedent on August 5, 1983.
The tractor is equipped with a “neutral start switch” (also known as a “starter *1438safety switch”) which prevents the engine from being started while the transmission is in gear. This device is part of the tractor’s normal starting circuitry. To start the tractor, the operator inserts the key in the ignition and turns it. Because of the neutral start switch, however, the engine will not start unless the transmission is in neutral.
However, it is possible to bypass the normal starting circuitry by placing a screwdriver or similar piece of metal between two terminals on the starter and the starter solenoid. This method is often called “bypass starting” because it bypasses the normal starting circuitry.1 When this method is employed, the neutral start switch is also bypassed and the engine can be started even though the transmission is in gear.
On October 8, 1983, the day before the accident, the tractor’s normal starting circuitry malfunctioned, making it impossible to start the tractor with the key. Decedent and his helpers therefore bypass started the tractor. By the next day, decedent and his various helpers had bypass started the tractor several times, without incident.
On the day of the accident, decedent and his friend Ralph Titsworth had been plowing with the tractor. When the men broke for lunch, Titsworth left one of the transmission levers in a position which allowed it to fall into gear when he turned the engine off. When the men returned from lunch, the tractor was therefore in gear. Decedent and Titsworth stood in front of the tractor and attempted to bypass start the engine by placing a screwdriver between the starter and the solenoid. The tractor started, hesitated, and then lurched forward, crushing the decedent under its rear wheels and killing him.
Decedent’s wife brought this wrongful death action claiming manufacturers’ strict products liability. Specifically, McMurray claimed the tractor was defective because it could be bypass started while in gear, and because Deere failed to warn decedent of this fact, thus making the tractor dangerous beyond the contemplation of the ordinary user possessing ordinary knowledge of the tractor.2 She claimed decedent’s death resulted from this defective condition and therefore sought compensatory damages. She also sought punitive damages, contending that Deere knew of the alleged defect, and further knew that bypass starting was a common practice and that operators of Deere tractors had been injured or killed in similar accidents.
Deere denied the tractor was defective and denied decedent’s death resulted from the alleged defect. Deere also asserted two affirmative defenses: first, that decedent assumed the risk of a known defect when he bypass started his tractor; and second, that the act of bypass starting constituted a misuse of the tractor. Specifically, Deere claimed that decedent had extensive experience with large pieces of earth moving equipment such as bulldozers, scrapers, graders, and loaders. Deere also claimed decedent failed to follow the operating instructions.
*1439The district court denied McMurray’s request for an instruction that if the jury found the tractor was defective, decedent’s failure to follow the operating instructions would not bar recovery. Over McMurray’s objection, the court instructed the jury on the affirmative defenses of misuse and voluntary assumption of the risk of a known defect. McMurray now seeks reversal, claiming the instructions misled the jury.
II
In this diversity case the law of Oklahoma governs. Oklahoma embraced the doctrine of manufacturers’ strict products liability, as expressed in the Restatement (Second) of Torts § 402(A), in Kirkland v. General Motors Corp., 521 P.2d 1353 (Okla.1974). See generally Pearson, An Overview of Oklahoma Products Liability Law: Kirkland v. General Motors Corporation and Beyond, 59 Okla.B.J. 1417 (1988) (hereafter “Pearson”). Under this doctrine,
one who sells any product in a defective condition unreasonably dangerous to the user or consumer or to his property is subject to liability for physical harm thereby caused to the ultimate user or consumer, or to his property, if (a) the seller is engaged in the business of selling such a product, and (b) it is expected to and does reach the consumer without substantial change in the condition in which it is sold.
Restatement (Second) of Torts § 402(A)(1).
Under Oklahoma law, a plaintiff must prove three elements to recover on the theory of manufacturers’ strict products liability: (1) the product was the cause of the injury; (2) the defect existed in the product at the time it left the manufacturer’s possession and control; and (3) the defect made the product unreasonably dangerous to the plaintiff or his property. Kirkland, 521 P.2d at 1363; Smith v. United States Gypsum Co., 612 P.2d 251, 253 (Okla.1980); Cunningham v. Charles Pfizer & Co., 532 P.2d 1377, 1379 (Okla.1974); see also Karns v. Emerson Elec. Co., 817 F.2d 1452, 1455 (10th Cir.1987); Brown v. McGraw-Edison Co., 736 F.2d 609, 613 (10th Cir.1984); Hurd v. American Hoist & Derrick Co., 734 F.2d 495, 499-500 (10th Cir.1984); Hagan v. EZ Mfg. Co., 674 F.2d 1047, 1050 (5th Cir.1982) (discussing and applying Oklahoma law); Mustang Fuel Corp. v. Youngstown Sheet & Tube, 561 F.2d 202, 206 (10th Cir.1977).
A product is unreasonably dangerous if it is “ ‘dangerous to an extent beyond that which would be contemplated by the ordinary consumer who purchases it, with the ordinary knowledge common to the community as to its characteristics.’” Kirkland, 521 P.2d at 1362-63 (quoting Restatment (Second) of Torts § 402(A) comment i (1965)); see also Brown, 736 F.2d at 613; Lamke v. Futorian Corp., 709 P.2d 684, 685-86 (Okla.1985). The only defenses to this type of action are lack of proof of causation beyond a mere possibility, voluntary assumption of the risk of a known defect, or abnormal use of the product. Kirkland, 521 P.2d at 1366-68; see also Smith v. United States Gypsum Co., 612 P.2d 251, 254 (Okla.1980); Fields v Volkswagen of Am. Inc., 555 P.2d 48, 56 (Okla.1976). See generally, 46 A.L.R.3d 240 (1972).3 The defense of contributory negligence is not available. Fields, 555 P.2d at 56; Kirkland, 521 P.2d at 1366-68; see also Saupitty v. Yazoo Mfg. Co., 726 F.2d 657, 660 (10th Cir.1984); Pearson, supra at 1421 & n. 70.
We turn to McMurray’s assignments of error regarding the instructions. We examine the instructions as a whole to determine whether they properly presented the law which is applicable to the issues. Marshall v. Ford Motor Co., 446 F.2d 712, 715 (10th Cir.1971); Messler v. Simmons Gun Specialties, Inc., 687 P.2d 121, 129 (Okla.1984).
A. VOLUNTARY ASSUMPTION OF THE RISK OF A KNOWN DEFECT
McMurray first argues the court erred by instructing the jury on assumption *1440of the risk.4 Specifically, she contends there was no such evidence in the record to warrant the instruction. We agree.
Kirkland recognized assumption of the risk as a valid affirmative defense in this type of action. However, there the court carefully explained that this defense differs from such a defense in negligence actions: “[cjomplicated semantic difficulties arise when the defense of assumption of the risk is considered. In order to avoid abuse of this legitimate defense, or confusion of same with its common law counterpart of the same name, it should be narrowly defined as voluntary assumption of the risk of a known defect.” 521 P.2d at 1366 (emphasis in original; footnote omitted) (citing Williams v. Ford Motor Co., 454 S.W.2d 611 (Mo.Ct.App.1970); Restatment (Second) of Torts § 402A comment n; W. Prosser, The Law of Torts, 3d ed., § 78). Under Kirkland, “there must be a showing that plaintiff knew of a defect unreasonably dangerous in nature, yet voluntarily used the product. Only then is he precluded from recovery under this defense,” Hogue v. A.B. Chance Co., 592 P.2d 973, 975 (Okla.1978) (emphasis in original).
This principle has been restated by the Supreme Court of Oklahoma, e.g., Clark v. Continental Tank Co., 744 P.2d 949, 954 (Okla.1987); Hogue v. A.B. Chance Co., 592 P.2d 973, 975 (Okla.1978); Jordan v. General Motors Corp., 590 P.2d 193, 196 (Okla.1979), and by this court when applying Oklahoma law, e.g., Smith v. FMC Corp., 754 F.2d 873, 876 (10th Cir.1985); Barber v. General Elec. Co., 648 F.2d 1272, 1277 (10th Cir.1981). There must be evidence sufficient for a conclusion that “appellants’ decedents knew of such risk and knowingly assumed the risk.” Smith, 754 F.2d at 877; Pearson, supra at 1421 & nn. 76, 77.
“The key to the question is factual. It is how specific [the injured party’s] knowlege of the [product’s] defect and the resultant risks must be in order for the trial court to be justified in submitting [an assumption of the risk] defense to the jury.” Bingham v. Hollingsworth Mfg. Co., 695 F.2d 445, 448 (10th Cir.1982) (applying Oklahoma law). Here, there was no evidence whatsoever, direct or circumstantial, that decedent knew of the alleged defect in the tractor: that it could be bypass started while in gear.
Deere had the burden of proving such knowledge in raising this affirmative defense. See Smith, 754 F.2d at 876; Bingham, 695 F.2d at 452; Pearson, supra at 1420 n. 58. Subjective awareness of the defect and consequent risk of injury must be demonstrated. See, e.g., Bingham, 695 F.2d at 448-49 (plaintiff admitted she knew the load she was pulling was great and that she had to be careful); Clark, 744 P.2d at 954 (“Plaintiff was well aware that the safety devices had been disconnected and/or removed and he was well aware, by his own admissions, of the inherent risk of using the piece of equipment without such *1441safety devices.”); Jordan, 590 P.2d at 196 (“There was evidence plaintiff knew the car was acting strangely, having a tendency to veer.”); cf. Steele v. Daisy Mfg. Co., 743 P.2d 1107, 1109 (Okla.Ct.App.1987) (“The potential for danger inherent in an air rifle is readily apparent_”).5
The only evidence cited by Deere on the decedent’s knowledge was summed up by Deere as follows:
Testimony was undisputed that McMur-ray was the owner and principal operator of the John Deere 4640 tractor manufactured by the Defendant. There was also testimony that on the previous occasions where McMurray had bypass started the tractor, he had placed an operator in the cab, or checked the gears before-hand. There was testimony that he had instructed his employees, including plaintiff herself, who assisted her husband in the operation of their heavy equipment, that all equipment should be taken out of gear when they were through operating it.
There was testimony that virtually all machines can be bypass started in gear, and that, if started in gear, these machines will move. There was also, according to the only witness to the accident, the dying exclamation of McMurray “It’s in gear” before the tractor ran over him and killed him.
Brief of Appellee at 9-10.
This evidence was insufficient to warrant submission of the affirmative defense to the jury. Any inferences that could be drawn constitute nothing more than pure speculation. Assuming decedent usually made sure other equipment was in neutral before starting, that he had extensive experience with similar equipment and had bypass started this tractor on other occasions, one cannot conclude that he knew this tractor could be bypass started in gear. Deere’s evidence supports conjectural inferences only. See Smith, 754 F.2d at 876 (evidence was insufficient to warrant submission of assumption of the risk defense when two steelworkers who were killed when a piece of steel being carried by an allegedly defective crane fell on them, because there was no evidence that they knew of the alleged defect in the crane). A showing that decedent should have known of the defect is not enough.
Because Deere had the burden of presenting proof of its affirmative defense which would support more than mere speculation, and failed to present such proof, it was error to submit the defense to the jury. As we did in Smith v. FMC Corp., 754 F.2d at 876-77, we must hold that this fundamental error requires reversal for a new trial.
B. ABNORMAL USE OF THE PRODUCT
McMurray next claims the evidence was not sufficient to warrant the submission to the jury of the affirmative defense of abnormal use of the product also termed “misuse” by the Oklahoma courts. Fields, 555 P.2d at 56.6 In Kirkland the court explained: “A second defense, well established in negligence cases, and applicable to manufacturers’ products liability is the defense of abnormal use. If the plaintiff is *1442using the product for some purpose for which it was not intended and is consequently injured, he should not recover.” 521 P.2d at 1366. The court expanded on this defense in Fields:
Generally, when we speak of the defense of misuse or abnormal use of a product, we are referring to cases where the method of using a product is not that which the manufacturer intended or is a use that could not reasonably be anticipated by a manufacturer. A distinction must be made between use for an abnormal purpose and use for a proper purpose but in a careless manner (contributory negligence).
555 P.2d at 56 (emphasis added); see also Pearson, supra at 1420-21. Courts applying Oklahoma law have continued to recognize the difference between use for an abnormal purpose, and careless use for a proper purpose. E.g., Fields, 555 P.2d at 57; Spencer v. Nelson Sales Co., 620 P.2d 477, 482-83 (Okla.Ct.App.1980). Other courts have recognized this difference when deciding factually similar cases. E.g., Lancaster v. Jeffrey Galion, Inc., 77 Ill.App.3d 819, 822, 33 Ill.Dec. 259, 263, 396 N.E.2d 648, 652 (1979); Ford Motor Co. v. Matthews, 291 So.2d 169, 174 (Miss.1974); Wyatt v. Winnebago Indus., 566 S.W.2d 276, 282 (Tenn.Ct.App.1977). For example, Matthews stated:
Ford next contends that [plaintiff’s] act of standing on the ground and starting the tractor while in gear was a misuse of the product. It is apparent that the failure of the safety switch to prevent the tractor from cranking in gear was a cause of the accident. The failure of the decedent to make sure the tractor was in neutral before starting [if that were true] may be characterized as the omission of a customary precaution, although there is no evidence that he was warned of this danger, or that he knew of the danger. Nevertheless, this was not such a misuse of the tractor as to relieve Ford from its strict liability for the defective condition of the tractor.
291 So.2d at 174, (emphasis added), cited with approval in Oklahoma Fields, 555 P.2d at 56; Spencer, 620 P.2d at 481 n. 8.
Deere attempts to distinguish Matthews by arguing that there the plaintiff used his key to start the tractor and was apparently unaware the safety switch was inoperative. Deere’s implicit conclusion is that bypass starting constitutes an abnormal use of the tractor. We disagree. As we have held in Part II-A, there was no evidence here sufficient to show that decedent McMurray knew of the alleged defect — that the tractor might be in gear and yet be bypassed started. Under Fields, decedent misused his tractor only if: 1) the method of using the product is not that which the manufacturer intended; or 2) is a use that could not reasonably be anticipated by the manufacturer. See 555 P.2d at 56.
Fields teaches that the injured party must make abnormal use of the allegedly defective product. Id. We must therefore examine the intended or foreseeable uses of the tractor. We think it obvious that Deere intended and realized that the tractor would be used for agricultural purposes, i.e. for plowing fields. See Stewart v. Scott-Kitz Miller Co., 626 P.2d 329, 331 (Okla.Ct.App.1981). Decedent was using, or attempting to use, his tractor for that exact purpose when the accident occurred.
Deere’s argument is subject to the same infirmity as the defendant’s argument in Spencer, 620 P.2d at 482. In that case, the plaintiff was injured when the highly flammable underwear he wore caught fire. Defendant argued that plaintiff “misused” the product because he should have worn protective outer clothing. The trial court instructed the jury on the affirmative defense of misuse and the Oklahoma Court of Appeals reversed, stating:
The instruction misguided the jury and should not have been given. There is no evidence that plaintiff was using subject clothing in any manner or for any purpose other than as an undergarment to keep himself warm. It is not disputed that he was wearing the clothing in a perfectly normal manner and in a way intended by its supplier. The judicial implication that he was not, and the granting to the jury authority to find he was not, was improper. What the de*1443fendant contends is that proper precaution dictated plaintiff wear leather coveralls to retard penetration of sparks and since he did not, his malfeasance — an act of negligence — contributed to the cause of his injuries. The distinction between “use for an abnormal purpose and use for a proper purpose but in a careless manner [contributory negligence]” [is recognized in Oklahoma].
620 P.2d at 482-83, (emphasis added).
Here, decedent was using and attempting to use his tractor for a proper purpose —plowing; any carelessness in his attempts to bypass start the tractor was only contributory negligence — not a defense here. Spencer, 620 P.2d at 482-83; Fields, 555 P.2d at 57; Hogue, 592 P.2d at 975; Lancaster, 33 Ill.Dec. at 263, 396 N.E.2d at 652; Matthews, 291 So.2d at 175.7 This is entirely different from a situation where a farmer is using his tractor for an abnormal purpose, for example attempting to demolish a building.
Deere also argues that there was misuse because the decedent failed to follow Deere’s instructions and warnings.8 We disagree. A similar theory of Deere’s was rejected in Reed v. John Deere, 569 F.Supp. 371, 377 (M.D.La.1983). There the court said that “it was certainly forseeable to John Deere that someone might start the engine of this tractor while not in the driver’s seat, in order to check repairs ... [t]his tractor was in normal use at the time of the accident despite the fact that the operator was not seated in the operator’s seat exactly in accordance with the manufacturer’s instructions.” Id.
The evidence of alleged misuse was relevant in defendant’s attempt to develop the defense that the decedent assumed the risk of the defect claimed, which we have held defendant failed to do. It was also relevant as to whether the tractor was a dangerous product in light of the warnings and instructions given. See Karns v. Emerson Elec. Co., 817 F.2d 1452, 1457-58 (10th Cir.1987). But, as the court concluded in Reed v. John Deere, supra, the tractor was not used in an abnormal manner or in an unforseeable way when the decedent bypassed started the tractor as he did. And, as we held earlier, there was not sufficient evidence to support an inference that he knew of the alleged defect — that such bypass starting could be done while the tractor was in gear. None of the warnings or instructions cautioned the decedent of the fact that this tractor might be in gear and yet it would bypass start.
In sum, the evidence failed to entitle the defendant Deere to a misuse instruction here and the giving of the instruction was in error as the Oklahoma Court of Appeals held in Spencer v. Nelson Sales Co., 620 P.2d at 482.
C. EFFECT OF THE ERRONEOUS INSTRUCTIONS
We must decide whether the errors in the charge were prejudicial so as to require reversal. See Joyce v. Atlantic *1444Richfield Co., 651 F.2d 676, 682-83 (10th Cir.1981).
In Smith v. FMC Corp., we stated: “Having held that it was error to instruct on the defense of assumption of the risk, the general judgment ... must be reversed and the case remanded for a new trial. A remand is necessary when, as here, we cannot ascertain from the record whether the jury found that the [product] was defective and, if so, whether the decedents ‘assumed the risk’ of working under it.” 754 F.2d at 877; see also Spencer, 620 P.2d 477 (Okla.Ct.App.1980) (unwarranted misuse instruction required reversal).
The same problem arises here. The jury might have based its verdict on a finding that the tractor was not defective. On the other hand, the jury might have based its verdict on findings that decedent “assumed the risk” of injury, or “misused” the tractor; these latter findings would be legally impermissible here because there was no evidence to properly support either conclusion. The general verdict frustrates a determination of the basis of the jury’s decision, and reversal and remand for a new trial are required.
Ill
Plaintiff McMurray contends that the district court erred by refusing to instruct the jury that any negligence by the decedent or his helper cannot bar her recovery. While this record is not such as to show reversible error on this ground,9 we discuss the issue because of the retrial to follow and the significance of the issue.
The record indicates that defendant Deere was permitted to examine witnesses, over plaintiff’s objections, concerning acts which might lead to an inference of negligence. See e.g., IV R. at 56, 37-91 (cross-examination of Ralph Titsworth). We cannot determine whether defendant Deere was only attempting to show — as it may— that these acts showed that decedent knew and assumed the risk of the defect, or misused the tractor, or that the decedent’s negligence itself caused the accident so that there could be no recovery. Kirkland, 521 P.2d at 1366. (“If some act of the plaintiff caused the injury, rather than the defective product itself, causation is missing, and the plaintiff may not recover.”) (emphasis in original). However, if the evidence is developed and argued so as to suggest that despite the effect of a dangerously defective product the factor of decedent’s negligence barred recovery, the theory would directly conflict with Oklahoma law in strict liability suits. Hogue v. A.B. Chance Co., 592 P.2d 973, 975 (Okla.1978); Fields, 555 P.2d at 55.
On remand, if evidence of such acts of alleged negligence is introduced, and it appears that the theory is being suggested that such negligence, as a contributing factor, would bar recovery despite the defect claimed, and that there is a danger the jury might so reason, then the trial court should give an instruction that contributory negligence is no bar to recovery in this products liability case.10
IV
Due to the reversible errors in the giving of the instructions the judgment is REVERSED and the cause is REMANDED for further proceedings.
*1445APPENDIX
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1. Keep all shields in place.
2. Make certain everyone is clear of machine before starting engine or operation.
3. Stop engine, lower implement to ground and shift to “PARK ” before dismounting. Wait for all movement to stop before servicing machinery.
4. Keep all others off equipment.
5. Keep hands, feet and clothing away from power-driven parts.
6. Reduce speed when turning or applying individual brakes.
7. Couple brake pedals together for road travel. 1
8. Use flashing warning lights on highway unless prohibited by law.
9. Use of seat belt with this protective structure is recommended for almost all operating conditions.
IMPORTANT
1. After starting engine, do not exceed 1000 RPM until oil pressure gauge needle is in operating zone.
2. Start engine immediately if stalled while working to provide turbocharger lubrication.
3. Before stopping warm engine, idle several minutes under 1000 RPM to cool turbocharger turbine.
4. After prolonged idle periods, see Operator’s Manual for starting instructions.
. This method is also known as “hot-wiring.” See Wyatt v. Winnebago Indus., 566 S.W.2d 276, 282 (Tenn.Ct.App.1977). Tractor operators frequently use this method to start their tractors when the normal starting circuitry fails. See, e.g., Armstrong v. Farm Equip. Co., 742 F.2d 883 (5th Cir.1984); Ford Motor Co. v. Eads, 224 Tenn. 473, 457 S.W.2d 28 (1970).
. It is important to understand McMurray’s exact theory regarding the alleged defect. She does not claim the tractor was defective because it could be bypass started, because the normal starting circuitry had malfunctioned, because the transmission levers could fall into gear, or because there was no parking brake. For cases involving those alleged defects, see Johnson v. International Harvester Co., 702 F.2d 492, 494 (4th Cir.1983); Wyant v. J.I. Case Co., 633 F.2d 1254 (7th Cir.1980); Lancaster v. Jeffrey Galion Inc., 77 Ill.App.3d 819, 33 Ill.Dec. 259, 261, 396 N.E.2d 648, 650 (1979).
The gravamen of her theory is that an ordinary consumer, after becoming familiar with the tractor, would believe it could only be started when the transmission was in neutral. An ordinary consumer would not understand that the neutral start switch would not function if the tractor was bypass started. Under her theory, Deere should have either: 1) designed the tractor so that it could not be started in any manner unless the transmission was in neutral; or 2) warned decedent that the tractor could be bypass started in gear.
. Other defenses have been recognized during the development of the theory, for example lapse of time/extended use, state of the art, substantial change in the product, and learned intermediary. See Pearson, supra at 1421-22.
. The court instructed the jury:
Voluntary Assumption of Risk of Known Defect
As a further defense, the defendant Deere and Company, Inc., alleges that the plaintiff's husband, Dennis Ray McMurray, assumed the risk of injury from the defect which the plaintiff contends caused his death. If you find each of the following propositions, the plaintiff cannot recover from the defendant Deere and Company, Inc.:
First: That a defect existed;
Second: That the plaintiffs husband, Dennis Ray McMurray, knew of the defect that existed; and
Third: That the plaintiffs husband, Dennis Ray McMurray, voluntarily exposed himself to the danger created by such known defect and was killed thereby.
While the test to be applied in determining whether Dennis Ray McMurray voluntarily exposed himself to a known defect is a subjective test, in the sense that it is his knowledge, understanding and appreciation of the danger associated with such defect which must be assessed, that determination is to be made upon your assessment of all of the facts established by the evidence. You are not compelled to find Dennis McMurray was unaware of the defect, if, in light of all the evidence, he could not have been unaware of the defect; and the factors of his age, experience, knowledge, and understanding, as well as the obviousness or lack thereof of the defect, will all be relevant to your determination of the issue.
I R. 118-19.
. In Bingham, we stated that “[t]rial courts in Oklahoma may not grant summary judgments on the basis that plaintiff assumed the risk ... without proof of specific knowledge in light of Hogue, but that does not mean that they cannot submit that defense to the jury where the direct evidence of plaintiff’s knowledge is unclear.” Bingham, 695 F.2d at 449 (emphasis added). In Bingham, however, the unclear direct evidence was an admission by the plaintiff, obtained during cross-examination, that she knew of potential risks involved with the use of the product. Id. at 448-49. In this case, however, there is no evidence that would indicate the decedent knew of the alleged defect and of the risks involved.
. The court instructed the jury here as follows:
Misuse
As the Court has previously instructed you, a manufacturer is liable for injuries caused by a defective product, only if that product was being properly used. Misuse is a complete defense in a manufacturers' products liability action. However, the defense of misuse is not applicable unless the product was being used for a use that was not intended by the manufacturer, or for a use that would not reasonably have been foreseen or anticipated by the manufacturer. There is no misuse when a product was used for a proper purpose, but in a careless manner.
. The record indicates decedent’s actions in starting the tractor as he did might have been forseen by Deere. As mentioned supra note 1, farmers have long been bypass starting their tractors. We also note that Deere was aware of this practice, and implemented a campaign to warn tractor owners of the dangers of bypass starting. See, e.g., Plaintiffs Ex. 36, 37, 40, 42, 47, 48, 49; II R. at 46-51; III R. at 72-81, 134-42. (Deere does not argue or present evidence that these warnings reached decedent).
. The defendant was permitted to offer evidence by its engineer, Mr. Strazheim, in which he stated that:
It has a safety alert symbol on the top, which is a triangle with an exclamation point in it. It says Caution. And the next instruction— the warning is Keep All Shields in Place. Number two, Make Certain Everyone is Clear of the Machine Before Starting Engine or Operation. Number three, To Stop Engine, Lower Implement to Ground and Shift to Park Before Dismounting. Wait for All Movement to Stop Before Servicing Machinery. Number four, Keep All Others Off Equipment. Five, Keep Hands, Feet and Clothing Away From the Power Driven Parts.
(Tr. Vol. IX, p. 10).
The defense attempted to show a violation of this warning. The warning, defendants Exh. No. 28, is reproduced as an appendix to this opinion.
Plaintiffs witness Sevart stated the operator’s manual told operators to start the tractor only from the seat and with the key. The operator’s manual itself is not in our record. VII R. at 34.
. For example, we do not have the closing arguments in our record.
. Defendant Deere relies on Bingham v. Hollingsworth Mfg. Co., 695 F.2d 445, 454 (10th Cir.1982). We feel that the instant case is not controlled by Bingham. In Bingham there was merely a question asked by the foreman of the jury whether the plaintiff had fastened her seat-belt and we said that this alone did not make it necessary to have an instruction that contributory negligence was not a defense. We feel that the instant case is a more serious one on the record of the trial before us in that there was very pointed development of testimony by the defendant in cross-examining Mr. Titsworth, the decedent’s helper, in a way that appeared to emphasize the theory of negligence by the decedent or Mr. Titsworth as a bar to recovery. See IV R. at 56, 37-91.
. Decedent previously had worked in his own landscaping business which utilized three small yard tractors. Rec. vol. VIII at 7.