HP Oil Pump from Mike's

The mention of a Husqvarna with no oil pump was a bit wrong. The 510 4/cycle engine used crankcase pressure to force oil up to the top end through a one way valve. Clever and interesting!
Exactly the one I was referring to, I am glad that someone remembers that anomaly besides me. IIRC it was a reed valve like any 2-stroke of the period, except that it was vented into the sump rather than the atmosphere. And Husky promoted the ambiguity of whether this thing could be said to have a 'pump' or not.
I mentioned it in the context of old time racers in search of the last flea power from the XS650/750 engine. Our breather, equipped with a PCV valve could make a functional top end oiler more than similar to the Husqvarna solution except that it would be a constant loss system. Never pass tech inspection which is a shame because done right it could eliminate the oil pump altogether, relying on splash feed for the big end and clutch/gearbox. Power handling would be a major problem.
 
I finally got around to making some filter sleeves. I went to Walmart and got the biggest, cheapest "open" filter (paper element not enclosed in a "can") they had. At about 5" long, that will give me 3 of the required 1.5" wide strips. At a bit over 3 feet long when the paper is stretched out, that should give me 6 x 3, or 18 filter sleeves. About $3 for the filter and a few cents worth of hot glue puts the cost at around 20 cents per filter sleeve .....

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Since the filter was an "open" style, cutting it apart was very easy using just your normal utility knife .....

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Examining the resulting "roll" of pleated filter paper revealed that they had joined the ends together by gluing the 2 end flaps back to back .....

mmnGHxP.jpg


I thought this might work well for making my little sleeves too. It certainly made the gluing process easy. I was able to glue it laying flat on the bench with no need to wrap the paper around a section of pipe. Match and square up the 2 end flaps, apply some hot glue between them, and just press them together .....

ZmrEuiU.jpg


The width of the pleats or distance between the folds made figuring out the proper length quite easy. 11 pleats worked out to just under the required 5.5" length. Add another pleat at each end for gluing and I was all set .....

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To install, simply fold the glued section over before inserting the filter .....

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I'll be trying one out with my next oil change.
 
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Looks good from this end, 5Twins.

... 18 filter sleeves. About $3 for the filter and a few cents worth of hot glue puts the cost at around 20 cents per filter sleeve ....

Maybe "Budget" falls a bit short to adequately describe those...?

Change out that first one after about 100-200 miles. See if it caught anything.
 
Gotta tell you that I really admire guys like you who venture into unknown territory and invent solutions to problems they encounter. Sort of like the Wright brothers and others who were inventing by the seat of their pants so to speak. Direct observation and intense thought have often as not come out ahead of academic math/measurement in getting to the root and solution of a problem. I have nothing against academics, I'll plead guilty on occasion to that myself, but it is highly susceptible to circular reasoning where you think you've thought the problem through so your answer must be correct, Yet it simply is wrong. Congratulations on you excellent photos. Good work
 
I don't have time to read the entire thread but I'd like to make some comments.
My talking about Dr Johns MG is about an all out racing attempt. The light oil adds HP due to low friction and pumping loss through the oil system. The point being, saying an all out racing XS uses the stock pump does not mean it is the best for a street engine. Racing engines want little drag from the oil system and damn the wear if we win. Using a larger pump with lighter oil may cool the engine better due to greater oil flow through the engine. Also, a racing engine at 9000 rpm is pushing approximately twice as much oil as a street engine at a 4500 rpm cruise given the same positive displacement pump.

There isn't much surface area on that homemade oil filter! Talk about oil drag. How much 20w-50 could be forced through?

Tom
 
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Tom, as far as my budget filter is concerned (same as 5Twins filter mod above), ALL of the 20w50 goes thru it.

An update note. Recently, after my latest experimental clutch tweak, I changed from Yamalube 20w50 to Valvoline 20w50. The top-end oil pressures really skyrocked at the cold 60°F temp. I started the bike normally, choke 'on', then glanced down at the pressure gauge. Started freaking-out, the needle was on ZERO!, and stayed there! Switched the choke off, getting ready for a quick shutdown, and the needle slowly rotated counter-clockwise to around 12psi. *Whew*, there was oil pressure after all. It had simply 'pegged' the needle while I wasn't looking.

After the initial hi-volume pump install, running Yamalube, the first start 60°F cold/idle pressure was around 13psi hi-idle, 6psi low-idle.

Then, since changing over to Valvoline, that same first start scenario produced upwards of 20psi hi-idle, about 12psi low-idle. Almost a doubling over the Yamalube.

Maybe the Yamalube acts like a 15w50, or 10w50, or the Valvoline acts like a 30w50? The book specs for oil viscosity ratings show that these two oils are nowhere near matched for their ratings at the cold end.

After reaching the hotter 180°F+ oil temps, both these oils showed 4psi at highway speeds.
So, I guess they're matched at the upper end of the scale?
 
I'm concerned just wrapping filter paper around the stock screen does not give enough filter area to easily squeeze the oil through. Of course a positive displacement pump puts it all through but the amount of pressure needed between the pump and the filter would be too high given the amount of flow. I believe the bypass may be held open and your simple wrap is only acting as a bypass filter. With either 650central or mikesxs proper solution, I feel a simple wrap is not a good idea.

I have thought about a paper filter for the stock screen location but it would always have pleats to maximize surface area.

Why don't you try 10w-40 with the large oil pump? The greater flow from the larger pump should have a thinner oil being a better choice.

Tom
And thanks guys for experimenting with this larger oil pump.
 
When I was researching for the spin-on filter, and gimme a break that was over 20 years ago, I picked the remote filter mount from J.C.Whitney for FORD because the 'O' ring diameter was smaller allowing a more graceful fit. In the FRAM catalog there are a LOT of variations but I found 1 with a blow-off valve at~15pounds, correct overall size to fit and more than enough filtration element to allow full flow hot or cold. The engineers gave me some numbers but I don't have them anymore, anyway, those compact car filters to fit the DODGE OMNI are like an exact match for our filter, in performance terms. You could screw on a wacking great Purelator PER1 if you wanted, but that might look kind of lame. Or not.
 
Good questions and concerns about the paper filtration restriction and bypass valve. My gut tells me it's not a problem, but we really won't know until someone plumbs-in more pressure gauge taps. I don't want to modify any early side filter covers, but I suppose I could mod a later cover with taps, and run it for this insight...
 
Know what you mean TWO MANY, I have 2 bikes with modified covers, and 2 spare covers that will not be modified. One of those is an early version without a window. Funny thing, the oil pump is perfectly smooth and glassy despite the big wad of crankcase filter screen I found jammed upstream in the main intake passage.
One of the modified cases was left in the parking lot of an old Yamaha shop that had closed and auctioned all their stuff. The other is from a derelict XS650 I found in the woods. Got help from a bunch of passing teenagers to toss it in my truck. Surprise! They thought I was dumping it! Good stuff, tidying up the woods.
 
One bike has an oil gauge tapped in. I moved it all over the place but no matter it showed ~5lbs at cold start and ~0lbs warmed up. Ambient temp. never made much difference. Used 20w50 Castrol mostly.
 
Well, it's next year, and I finally got around to modifying a 447 side filter cover and added a tap to measure pump pressure, before the side filter.

XS1B-OilPressures01b.jpg


Temporarily mounted the pump's 0-30 psi gauge atop the 0-15 psi gauge.

XS1B-OilPressures02b.jpg
 
To recap the configuration, this bike has:

- High volume 12mm oil pump
- OEM sump filter screen (150 micron filtration)
- OEM side filter screen (150 micron filtration)
- Paper filter sleeve over the side filter (10-5 micron filtration)
- Valvoline 20w50

The main question was if the high volume pump puts out so much pressure as to blow the sidefilter's bypass valve, allowing unfiltered oil to enter the main oil gallery.

First, consider that the OEM sump filter passes particulates of 150 micron and less, as compared to the coarser aftermarket screens, which filter down to 350 microns.

XS650-NewOldSumpFilters2.jpg


The OEM side filter is of the same mesh, and isn't providing any extra filtration. It DOES serve as a backup filter in the event of sump filter failure. Aftermarket side filters are also of the coarser mesh, filtering down to 350 microns. I chose to remain with OEM filters.

The paper filter sleeve can provide filtration anywhere between 25 to 5 microns, depending on quality of filter material. My sleeves are cut from Fram filters, which should be good to 10-5 microns. If any oil gets around it, it'll be the 150 micron stuff from the sump filter screen. So, in this respect, I consider the paper sleeve as a useful addition. Nothing lost if it's bypassed...
 
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Cold start, 73°F, idling about 1100 rpm
Oil pump pressure: 15 psi
Topend pressure: 7.5 psi
XS1B-OilPressures03.jpg



Oil starting to warm up, 96°F, engine above 3000 rpm.
Oil pump pressure: 20 psi
Topend pressure: 11 psi
XS1B-OilPressures04.jpg
 
Oil warmed up, 175°F, engine idling.
Oil pump pressure: 2 psi
Topend pressure: 1.5 psi
XS1B-OilPressures05.jpg



Oil warmed up, 182°F, engine above 3000 rpm.
Oil pump pressure: 5.5 psi
Topend pressure: 4 psi
XS1B-OilPressures06.jpg
 
Goofing with the cold starts, choke, throttle, and smartphone, I forgot to get a pic of cold high-idle. I'll try again tomorrow, when it's colder, and get one with engine over 3000 rpm.

So far, though, there was never an instance where oil pressures were high enough to blow the side filter's 14 psi bypass valve...
 
Video of cold 1st start.
*Oofing* and *grunting*, I sound tired. Old man, old bike.


Please bear in mind that the main gallery pressure will be between the oil pump pressure and the top end pressure, as the top end oil must pass through a restrictor at the base of the front oil pipe...
 
Great video 2M! However, I would be concerned that the relief valve is lifting, during the first 2 or 3 minutes as the oil pump pressure pegs the 30 gauge to maybe 35 psig. Unfiltered oil could be getting into the engine??
 
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