This is my second Warp 9 rim on the back of my YZ250 and both rims have failed in the same manner. The first rim lasted about 15 hrs before it started to crack on the weld and the second one started cracking after the first ride, now at 7 hours the crack is wide enough for me to get my fingernail in on one side. I e-mailed Warp 9 on the first rim and they wanted me to send in the entire wheel assembly my cost to them so they could check it out. So that would have added $25 to the cost of that rim. I told the guy I was corresponding with that I simply wanted a new rim so I could mount it up and have minimal down time. I also agreed to ship the rim to them once I recieved the new one. Warp 9 was not willing to do anything other than have me ship my wheel to them. Fortunately I bought the rim from Rocky Mountain atv/mc and they were very helpful in getting me a new rim shipped to me at their cost and return postage on the cracked one also at their cost. I have come to the conclusion that these Warp 9 rims must have poor welds and quality control is not a priority. And apparently, neither is costumer satisfaction. I mounted both these rims myself and torqued the spokes to 2.2 ft/lbs per the manual. It should be noted that I aslo have a Warp 9 rim on the front that I mounted myself and have not had any issues with it.......yet. Anybody else have problems with the Warp 9 rims? I'm now in the process of purchasing an Excel rim and should have done that in the first place I suppose. But, thought I could save a few bucks.