SUMMARY ORDER
Plaintiffs-Appellants Mary Jane Glow-czenski and Jean Griffin, individually and as the co-Administrators of the estate of the late David Glowczenski appeal from (1) the district court’s Memorandum and Order, dated March 22, 2012, granting Defendants’ Motion to Preclude Plaintiffs’ Expert Witness; (2) the district court’s Order, dated June 13, 2012, denying Plaintiffs’ Motion for Reconsideration of the district court’s decision of March 22, 2012; (3) the district court’s Memorandum and Order, dated September 28, 2012, denying Plaintiffs’ Motion for Leave to Substitute an expert witness; (4) the district court’s Memorandum and Order, dated March 5, 2013, granting Defendant Taser International, Inc.’s (“Taser”) Motion for Summary Judgment; (5) the district court’s Order, dated August 19, 2013, granting a partial final judgment pursuant to Federal Rule of Civil Procedure 54(b) in favor of Taser; and (6) the final judgment as to Taser, dated September 13, 2013. We assume the parties’ familiarity with the un*725derlying facts, procedural history, and issues for review.
The district court has not entered a final judgment as to any Appellee except Taser. The issues raised on appeal against the non-Taser Appellees are neither “inextricably intertwined” with any issue properly before us nor “necessary to ensure meaningful review of the district court’s ruling.” Swint v. Chambers County Comm’n, 514 U.S. 35, 51, 115 S.Ct. 1203, 131 L.Ed.2d 60 (1995). We therefore decline to exercise pendant jurisdiction over the non-Taser Appellees. See Myers v. Hertz Corp., 624 F.3d 537, 553 (2d Cir.2010).
Appellants argue that the district court erred when it excluded the medical causation opinions of forensic pathologist Dr. William Manion and also erred when it denied their motion for reconsideration on the same issue. Upon a thorough review of the record, we conclude that the district court did not abuse its discretion in excluding Dr. Manion as an expert witness, because his opinion lacked a sufficiently reliable scientific basis. See Boucher v. U.S. Suzuki Motor Corp., 73 F.3d 18, 21 (2d Cir.1996). As the district court noted, Dr. Manion performed minimal research on Taser’s ECD technology in preparing his expert opinion, had trouble differentiating between ECD’s two operational modes, and could cite no data on the ECD’s likelihood of causing muscle contractions. Even after spontaneously amending his testimony to opine that the ECD caused muscle contractions ‘indirectly’ by inflicting extreme pain that would cause a person to contract his muscles to avoid the stimulus, he could not explain how or at what point such a reaction to pain could trigger secretions of lactic acid so as to accelerate respiratory compromise. We hold that reconsideration would not “reasonably be expected to alter” the district court’s conclusion and thus that the district court did not abuse its discretion. Kolel Beth Yechiel Mechil of Tartikov, Inc. v. YLL Irrevocable Trust, 729 F.3d 99, 108 (2d Cir.2013).
Appellants also contend that the district court erred in denying their motion to reopen discovery and to substitute a third, unnamed causation expert for Dr.-Manion. Here, Appellants waited nearly six months after learning that Dr. Manion would be excluded, until well after Defendants had been put to the burden of preparing motions for summary judgment, to seek leave to reopen discovery and present a new expert. Even then, Appellants did not identify any expert, or even represent that they had located one, let alone proffer an expert opinion. Moreover, they offered no explanation for their eight-year failure to properly support their causation claims with competent expert testimony. Under these circumstances, the district court acted appropriately within its discretion when it denied a third bite at the apple. See Softel, Inc. v. Dragon Med. & Scientific Commc’ns, Inc., 118 F.3d 955, 961 (2d Cir.1997).
Finally, Appellants argue that the district court erred in granting summary judgment to Taser. Yet Appellants concede that, absent an expert on cause of death, they cannot prevail on either their products liability or wrongful death claims. We agree with the district court that Appellants’ tort claims against Taser fail for want of evidence on causation. See El Sayed v. Hilton Hotels Corp., 627 F.3d 931, 933 (2d Cir.2010).
We have considered Appellants’ remaining arguments and find them to be without merit. For the reasons stated above, the appeal is DISMISSED as to all Appellees except Taser. As to Taser, the judgment of the district court is AFFIRMED.