The biggest problem i have with this motor is that i love the way it drives, it just suits me. hence i have bought another one, hoping it gives me a good life. i actually got a fair bit of life out of my last one. Probably 10 gallons, with a conrod and bearing change, but if you do the sums on that it doesn't work real good vs my novarossi 421b i paid $50 dollars more for and have got 12 gallons or so out of and its still going strong (and only recently changed the rod). its a pitty the 421 just never came out of corners smooth for me.