So at what point do you add more oil? I checked my oil level today and it's right at the bottom of the sight glass. Should I add oil now or wait until the first service? Never bought a new bike where the oil level wasn't topped off.
Checking oil on 2023 Hayabusa
- Thread starter wellcraft
- Start date
Your oil is at a safe level.
Is another half a quart or so better?
I think so.
When should you add more?
Either at the point that you feel the engine is broke in, or better yet, at what point it makes you feel comfortable...like now.
There is almost as much talk about proper break-in as there is oil itself.
The consensus at this point seems to be somewhere between an agressive break-in, and that it doesn't really matter.
Revzilla/Common Tread have a video breaking in 2 engines, 2 different ways, taking them apart and measuring and inspecting, and finding no difference.
We could argue fine details to no end, but, at the end of the day, you are not harming a thing by adding another half a quart of oil for peace of mind.
But, if that cost you .2 hp on the dyno...you have my apologies
lol
Is another half a quart or so better?
I think so.
When should you add more?
Either at the point that you feel the engine is broke in, or better yet, at what point it makes you feel comfortable...like now.
There is almost as much talk about proper break-in as there is oil itself.
The consensus at this point seems to be somewhere between an agressive break-in, and that it doesn't really matter.
Revzilla/Common Tread have a video breaking in 2 engines, 2 different ways, taking them apart and measuring and inspecting, and finding no difference.
We could argue fine details to no end, but, at the end of the day, you are not harming a thing by adding another half a quart of oil for peace of mind.
But, if that cost you .2 hp on the dyno...you have my apologies
lol
If your oil level is within the sight glass you have nothing to worry about, you can add some oil now or correct it on the first oil change and the engine will never know the difference either way. I only added oil to mine for my own comfort because I have severe OCD and am a perfectionist.
Cruising180
Registered
I drove semi trucks for over a decade. Those things hold 10-16 gallons of oil and still when warmed up are between 40-60 psi in oil pressure. The oil pump design and it corresponding components are what dictate the amount of oil pressure not the amount of oil.
I drove tractor trailers for as long myself.
Yes, oil pumps have mechanical limits...which are not always met by a set volume of oil.
You are also talking about an apples to oranges comparison in engines.
Cruising180
Registered
The type of engine doesn't matter. Fluid dynamics don't change. The viscosity of the fluid the diameter of the passage it's flowing through and the output of the pump are what determine PSI.
No need to be anal about oil level on the Hayabusa. If the bike is standing up, as long as your oil is not too far below the bottom line on the sight glass, it really makes absolutely no difference in oil pressure, reliability, engine life, or anything else for that matter.
I will try and explain this in technical terms, which most folks normally don't interpret, but here we go:
Below are two pictures, the one shows the actual oil pump and its location from the Hayabusa factory manual, the other shows how these pumps work.
The Haybusa uses a Gerotor pump, in Engineering terms we call that a Trochoid pump. It is pretty close to a positive displacement pump, although there is a little bit of slip, but a lot less than a normal impeller centrifugal pump. It follows that the static head (oil level above the pump) has an insignificant effect on the volume and pressure the pump actually produces. The pressure and volume is produced by the velocity head of the pump only, as long as it is fully immersed in oil.
So in simple terms, as long as the pump is not pumping air, is immersed in oil, the only thing that affects the volume of oil pumped and the oil pressure is the revolutions per minute that the pump is turning, aka engine RPM. Oil level has absolutely no effect on volume or pressure. If the pump starts pumping air, we get cavitation, which can be handled for short periods of time, such as dragging a knee, or wheelie, but for extended periods of time, we will start doing engine damage. Normally manufacurers build in a safety factor, so if you forgot to check your oil and it is not too far below the bottom line on the sight glass, you should still be OK, although I would not recommend that.
I will try and explain this in technical terms, which most folks normally don't interpret, but here we go:
Below are two pictures, the one shows the actual oil pump and its location from the Hayabusa factory manual, the other shows how these pumps work.
The Haybusa uses a Gerotor pump, in Engineering terms we call that a Trochoid pump. It is pretty close to a positive displacement pump, although there is a little bit of slip, but a lot less than a normal impeller centrifugal pump. It follows that the static head (oil level above the pump) has an insignificant effect on the volume and pressure the pump actually produces. The pressure and volume is produced by the velocity head of the pump only, as long as it is fully immersed in oil.
So in simple terms, as long as the pump is not pumping air, is immersed in oil, the only thing that affects the volume of oil pumped and the oil pressure is the revolutions per minute that the pump is turning, aka engine RPM. Oil level has absolutely no effect on volume or pressure. If the pump starts pumping air, we get cavitation, which can be handled for short periods of time, such as dragging a knee, or wheelie, but for extended periods of time, we will start doing engine damage. Normally manufacurers build in a safety factor, so if you forgot to check your oil and it is not too far below the bottom line on the sight glass, you should still be OK, although I would not recommend that.
LOL, you will find very few folks here have a background in fluid dynamics, so the word means nothing to most. You have to just learn to live and let live.
I know lots about fluid dynamics....if I drink too much water before I go to bed, I have to get up and pee during the night.....
........or is that old guy dynamics.....I get the two confused.....
Cruising180
Registered
Hey MEEEE TOOOOOO lolI know lots about fluid dynamics....if I drink too much water before I go to bed, I have to get up and pee during the night.....
........or is that old guy dynamics.....I get the two confused.....
dcnblues
Registered
I have a personal disagreement in that while I have no background, there's nothing in the world more beautiful to me than fluid dynamics. A good education would teach people that such beauty should be appreciated. I can blow smoke rings for hours, or watch drops of ink hit water, or even tornado footage. But yeah, most people have no idea what the word fluid means...
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dcnblues
Registered
My personal philosophy is that what we're talking about is a reservoir for oil leaks. The top line in the sight glass and no more means you don't have too much oil and it won't be a problem for the engine, and while the Hayabusa is a pretty tight bike without chronic oil leaks, they can happen. And when they happen it can take a while to notice it. And by the time you do, maybe the oil is at the lower line in the sight glass. The difference between the two lines is your Reservoir for noticing an oil leak. So my preference is to always keep it topped off.
You seem to have some great experience practicing the science. We are not all that smart ass.
In fluid dynamics, you have differential equations for newton's laws, navier-stokes law, the gaseous equation of state, ohm's law, heat transfer, and maxwell's equations to solve that are all coupled together: for a given mass element in the plasma, you have to sum the magnetic, electrostatic, inertial, friction, and pressure etc.
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