HP Oil Pump from Mike's

[dps650rider]

Got to try it out a couple times but it was still a bit cool outside and it always gets noisier as the temperature increases. I will say that so far it does seem to be quite a bit quieter than it was.

TwoMany, what oil pressure do you get when at operating temperature at 3000, 4000, 5000, etc RPM's?

 

[TwoManyXS1Bs]

Dps650rider, this is 182°F, just over 3000rpm. Around 5.5 psi main, 4psi top.

Haven't done higher 230°F temps, yet. But if it's proportional and typical of my readings from the original 8mm pump, I'd expect pressures to drop about 1 psi from that pic, and recover about 1 psi at the higher revs...

 

[dps650rider]

Have you checked at higher RPM's?

I wonder what it would be near redline.

 

[TwoManyXS1Bs]

Dps650rider, no, I haven't been monitoring hot/hi-rpm pressures. It hasn't been hot enuff out here yet for that kind of stress test.

I've been mostly focused on:
- Cold startup and idle pressures
- Warm idle and 3.5K rpm pressures.
- The cold viscosity differences of Yamalube and Valvoline.
- Pressure differences with/without the BOF.

My main interests were hot idle oil delivery to the top end. I don't think that hot hi-rpm pressures will be much more than in the pic above. But, I'm planning a ride to town tomorrow, and will try to note the pressures.

My other interest is if others experience similar, or vastly different top-end pressures, as reported by DogBunny...

 

[dps650rider]

TwoMany, Sounds like you are interested in the pump for the same reason I have been for quite some time, top end oil at low RPM. There is evidence that this is lacking like the common problem with wear and galling of the tappets, one of the reasons I went to elephant foot adjusters. With them I have occasionally heard a noise at idle that sounds like a foot chattering as it rubs on the valve stem, another indication.

Quite a while ago with the stock pump I "tested" top end oiling at idle by removing a cover and starting it but I really don't think that tells you anything. I think a lot of the oil that sprays out is the result of the pistons pumping it out with the air flow.

My only concern with the bigger pump is the additional amount of torque required to drive it. I did some searching on automotive engines and apparently on some (Ford was mentioned) the drive gears were not up to the task.

From what you have been measuring it doesn't sound like a problem when hot but since you have gauges installed we could get a pretty good idea.

 

[TwoManyXS1Bs]

Today was a beautiful day for riding. Afternoon temps in the 80's, but nowhere near hot enuff to get my oil temps into the 200's. So, I'll just report what pressures were displayed with sump oil temp at 182°F.

Report of XS1B 12mm oil pump pressures at 182°F (4-8-2017)
Budget Oil Filter (BOF) installed
Valvoline motorcycle oil 20w50

Temp .. RPM ... Top ... Main ... (Main, estimated, w/out BOF)
182° ... 3000 ... 3.5 ...... 8.0 ..... (6.0)
182° ... 4000 ... 5.5 .... 13.0 ..... (9.8)
182° ... 5000 ... 7.0 .... 16.0 ..... (12.0)
182° ... 6000 ... 8.0 .... 18.0 ..... (13.5)

Just going by what I've observed over this past couple months, it would seem that pressures are influenced by (in order, strongest first):

- Oil temperature
- Oil viscosity rating
- Oil brand
- Engine rpm
- Oil pump size and condition

Of course, this is just an opinion. Highly debatable.

It's worth noting that the +50% 12mm oil pump produces equal flowrate to the OEM 8mm pump at 50% reduced rpms. In the table above, I'd expect the 8mm pump, at 6000 rpm, to produce flowrate and pressures similar to the 12mm pump at 4000 rpm. Or, 1200 rpm idle with the 12mm pump should see similar flowrate and pressures as the 8mm pump at 1800 rpm...

 

[TwoManyXS1Bs]

...My only concern with the bigger pump is the additional amount of torque required to drive it...

Okay, I think I can calculate that. I need to find the teeth-count of the pump's geartrain, then calculate the HP requirements for the various flowrates and pressures, then derive the pumpshaft torque values. Need a nap, first...

 

[TwoManyXS1Bs]

The question is, how much torque is transmitted thru the oilpump's driveshaft.

Warning, *Math* is involved here. If you just wanna know the answer, skip all this gobbeldygook and go to the bottom paragraph.

RPM is engine Revolutions per Minute
GPM is oil flowrate in Gallons per Minutes
PSI is gauge pressure in Pounds per Square Inch
HP is HorsePower (33,000 FT-LBS per minute)
TQ is Torque (in Foot-LBS)
TQI is Torque (in Inch-LBS, TQ * 12)

Stated oil flowrate for the OEM 8mm pump:
1.3 liters/minute (1.37 quarts/minute) at 1000 rpm

Convert the flowrate to GPM:
GPM = 0.000343 * RPM (8mm pump)
GPM = 0.000515 * RPM (12mm pump, +50%)

Hydraulic (fluid power) HorsePower formula:
HP = PSI * GPM / 1714

Engine HorsePower formula:
HP = TQ * RPM / 5252
Transpose to find Torque:
TQ = HP * 5252 / RPM

Substitute HP (from the fluid power formula):
TQ = (PSI * GPM / 1714) * 5252 / RPM
TQ = (PSI * GPM * 5252) / (1714 * RPM)
Simplify:
TQ = PSI * GPM * 3.064 / RPM

For the 8mm pump:
Substitute GPM with the stated oil flowrates:
TQ= PSI * 0.000343 * RPM * 3.064 / RPM
The RPMs cancel each other out:
TQ = PSI * 0.000343 * 3.064
Simplify:
TQ = PSI * 0.00105 (Foot-LBS)
TQI= PSI * 0.0126 (Inch-LBS)

For the 12mm pump:
Substitute GPM with the stated oil flowrates:
TQ = PSI * 0.000515 * RPM * 3.064 / RPM
The RPMs cancel each other out:
TQ = PSI * 0.000515 * 3.064
Simplify:
TQ = PSI * 0.00158 (Foot-LBS)
TQI = PSI * 0.0189 (Inch-LBS)

Notice how RPM is now conveniently out of the equation.
Those torque values are for the engine driving gear.

The oilpump geartrain:
17 tooth engine (driving) gear
43 tooth oilpump (driven) gear
Torque multiplication = 43/17 = 2.529

Now, multiply the TQI values to get the oilpump shaft torques:

For the 8mm pump: TQI = PSI * 0.0318 (Inch-LBS)
For the 12mm pump: TQI = PSI * 0.0478 (Inch-LBS)

*****************

So, suppose that you're showing 40 psi on the 12mm oilpump,
the pump's shaft torque would be 1.9 Inch-Lbs

I dunno, man. Think sumpthin's gonna break?

 

[dps650rider]

Too late for me to absorb the math tonight, I'll take a look at it tomorrow unless it is nice after work again. At any rate, it doesn't sound like much, it just made me wonder when I saw 50 or 60 PSI on you gauge.

What type of Valvoline were you using, conventional or synthetic? Anymore I use synthetic because it doesn't lose viscosity with age like the conventional oil.

 

[TwoManyXS1Bs]

I'm using the Valvoline 20w50 conventional, $6 per quart.

That's another handy thing about the oil pressure gauge. Once you get accustomed to the numbers, a drop in pressures would indicate time for an oil change. Well, for the conventional anyways...

 

[dps650rider]

OK, not so nice out this evening so I went through the math which makes perfect sense. Thanks much for the insight into this TwoMany.

 

[TwoManyXS1Bs]

Summertime, temps getting into the 100's down here.
Hot enuff to get 230°F - 240°F sump temps.
Added the 182°F pressures from April into this chart.

 

[Bob Kelly III]

Question: if you bought a High volume oil pump and it was binding as you turned it through by hand Why not put fine valve grinding compound in it and spin it with a drill until the binding goes away ?
that seams like the most logical course of action to me rather than throw it away.
then after checking the clearance with a feeler guage and if it's still in specks, use it !
.....2M : is there anything wrong with this fix ? what am I missing ? besides the obvious of replace it to begin with !
...... and Nice Info on the oil pressures and temps 2M well done !!!!!!!!!
Bob......

 

[TwoManyXS1Bs]

Using the bigger hammer, Bob?

That method may make sense with a lotta things, but I wouldn't advocate that on a trochoid pump.

Pump rotor fits are already close, the grit will bind it up worse.
The rotor geometries are critical, you'll be grinding away good sections.
The rotor shaft is a bit loose fit in the cover by itself. Unless done while fully assembled, it'll cock over and you'll be grinding unparallel surfaces.
The grinding grit will get everywhere and gouge the sides.
The result will be a pump that looks like it ate a lotta engine parts, needing replacing.


What size ball-peen hammer is used to set a wristwatch?

Ans: Any size will do. The wristwatch will be accurate twice daily...

 

[Bob Kelly III]

yes it would add allot of ware no doubt but it will smooth out the binding, I've done it before on a VW oil pump, it's gear type pump is just as critical as the one on the xs650 I think I would try that as a last resort before shit-canning the pump ...especially if it's a NEW pump.
you can carefully add the fine grounding compound to the places that need relieved only .... yes it will spread to all parts very quickly
but with judicious use I think it could cure the problem !
yah it's using a bigger hammer kind of thing and should be used only as a last resort because it could add 10,000 miles in a minute of spinning.
but...at least the pump would be useable then .
it's an OPTION, perhaps not the best option, but it is an Option !
it really depends on how bad the pump is I guess !
...... for what it's worth !
.....
Bob........

 

[TwoManyXS1Bs]

I had also ordered the MikesXS stock 8mm pump rotor set. Comparing it to my OEM pump revealed a slight difference in the curvatures of the trochoid fingers and valleys. Just playing around with intermix fits, found that one intermix combo was too loose, and another just plain locked-up. I certainly don't recommend this intermixing.

You could probably "big hammer" the thing to spin, but the fits of rotor fingers would oscillate close/open/close/open, allowing internal leakage, and I doubt it would deliver the flows and pressures normally expected of it. Trochoid geometries are much more critical compared to gear pumps...

 

[Bob Kelly III]

humm, sounds like the smartest thing to do Was throw it away ! Gads ! how can they sell crap like that and stay in business !?!?!?!
......
Bob......

 

[TwoManyXS1Bs]

If I came across a pump that was binding, I'd chase down the issue to find just what/where the interference is. Using "Dykem blue" layout/marking fluid would be a good choice to find the exact spots. Then, apply the smaller hammer on just those spots.

Would love to be able to go back in time to see just what those "binding" reports are about. My gut tells me that they were probably experiencing the interference fitments of the pump body and casecover, as addressed in post #45. If the pump body doesn't set fully and perfectly flat/flush (without being forcibly bolted down), the rotors definitly bind up...

 

[Bob Kelly III]

like perhaps a fine stone on the parts that have the blue on them eh ? care would have to be used to keep it flat and only remove the mark and do the blueing again.... touchy but far better than my earlier method ! LOL
.....
Bob.......

 

[JAX71224]

huh. then maybe I should install a oil pump on my wifes standard bread horse so I not scared shitless to ride it? Would take out 3-4 hp if I read that rite? lol What kind of balls out racing are you planning to do on this motor?
I agree with the street bike statement. I have a 2003 Suzuki marauder I call my long runner. Its my cruiser, never sees the redline at a embarrassing 5k, mostly because of the over sized front sprocket and undersize rear sprocket.
I cant imagine oil splash getting to the outer lobes of the cam. Centrifical force throws it up, not around, even with splash off the top of the cam cover, I just cant see in my mind enuf oil to get over there.
I think those husq's were 2 strokes?
I just cant believe someone would run without a oil pump in a race bike, or anyother bike. Not only does it lubricates, it cools.
Dragsters and funny cars have oil pumps, and they rebuild them after every race. That there is a high dollar hobbie. If they could pick up 4 hp with out a pump, they would do it. They already run without water pumps, radiators.

Ever heard of speedway bike racing? nitro motors, 500 cc singles,no oil pump........