jumpship wrote: Bike is a 1980 KZ750-4. I am pretty sure overfilling the engine with oil was the cause. I just put CR Special 29mm carbs on and got the bike running mint, air/fuel ratio was good checked plugs heavily throughout tuning process so i the bike was running like a beast real nice. I topped off my oil when it was getting low i checked the glass, i overfilled it so that there was a TINY bubble of air in the sight glass with the engine 100% cold. After rides i would notice the engine really really abnormally hot at the same time i noticed the sight glass was full without any space. I know im an idiot but we all have to learn somehow right? I commute with the bike so i was too lazy to drain the oil out. On my way home with the bike fully warmed up today i was merging onto a highway and 8k rpms is when she popped and the oil light went on, thankfully an exit was near by. and upon inspection there is literally 2 holes punched out in front of the crankcase on the front side of the motor. heres why i believe it was not air/fuel ratio related and also why i believe it was too much oil (built up too much pressure especially with high performance carbs) : The bike fires right up with no abnormal clunking or anything, infact it sounds exactly the same, firing on all 4 and sounds real strong and good actually, If the bike was running too lean and popped the engine i dont think it would still be able run like it is able to now, and the plugs would have looked atleast a little bit whitish, infact they were all dark brown. What do you guys think? Do you agree with me that the overfilling of oil created so much pressure with the combination of the new CR Carbs that at 8k rpms the crankcase had no where to put the pressure except through a hole in the front of the crankcase? The bike still runs and fires right up so there is no piston problem i know for sure, and im currently in search for a new engine btw.... Does anyone know of any other engine that will slip right in? Any comments? I Know guys i deserve to be shot :sick:
WTF?.......
