I also have never had a prob with novarossi bearings. I think if people have probs I would ask have they been changed and check that hey have been alined corectly. Also running temps i run my 35+21 nova and my friend runs his 35+21 jp nova at about 100 to 115 deg C we get great paformance and 5 to 6min runtime from mine and they last like a very very long time ive done 30ltrs of fuel on one bearing front and rear cheange at 15ltr + rod piston pin and clips all at 15ltr mark its now due for a second rod.