Indydave
CB750 Enthusiast
My 1979 750f dohc slipped the timing chain and I believe I have it correctly timed but it won't fire even though I know I have spark and I have sprayed starting fluid directly into the cylinder while cranking it. I saw the following advice in another thread and I would like someone to help me understand if I could have it timed to the exhaust stroke and not the compression stroke. Does this advice seem correct?
" When the 1.4 S.F mark is on you are at TDC......................................BUT, WHICH ONE???
There are TWO, a 4 stroke has to rotate TWO complete revolutions (720 degrees total) to finish an entire cycle, why it's called a 4 stroke...........2 strokes up and 2 down..........intake, compression, power stroke and exhaust, in that order. Two TDCs happen then, one at the end of exhaust stroke and beginning of intake, and the other at end of compression and beginning of power."
Easiest way is to yank #1 plug and with finger over the hole turn the engine over until you feel the compression beginning to push your finger off, the next TDC (1.4 S.F) you roll to will be the correct one if you don't go too far. Engine MUST be turned counterclockwise on that side (left).
" When the 1.4 S.F mark is on you are at TDC......................................BUT, WHICH ONE???
There are TWO, a 4 stroke has to rotate TWO complete revolutions (720 degrees total) to finish an entire cycle, why it's called a 4 stroke...........2 strokes up and 2 down..........intake, compression, power stroke and exhaust, in that order. Two TDCs happen then, one at the end of exhaust stroke and beginning of intake, and the other at end of compression and beginning of power."
Easiest way is to yank #1 plug and with finger over the hole turn the engine over until you feel the compression beginning to push your finger off, the next TDC (1.4 S.F) you roll to will be the correct one if you don't go too far. Engine MUST be turned counterclockwise on that side (left).