HP Oil Pump from Mike's

Okay, RG. Here's a snapshot in that first 2-3 minutes, oil temp at 63°F.

XS1B-OilPressures07.jpg

The oil pump pressure gauge is showing about 35 psi.
The stop peg is a little more to the left.
The top-end pressure gauge is showing about 17 psi.

The main gallery pressure is somewhere between those two.

I think I'll try to duplicate this video/scenario, leaving the entire side oil filter (screen and sleeve) out of the engine. I believe those readings would give a fairly good idea of what the main gallery pressures are.
 
Two more videos. Trying to duplicate the conditions of that first video.

This time WITHOUT the side oil filter.

Part 2, a couple of degrees warmer.
I screwed-up and called out 20psi, when I should have said 25psi:

Part 3, a few degrees colder.
Fresh Valvoline 20w50 (same oil), old oil had about 500 miles on it.


Not easy doing this, get just 1 chance in the morning to get it right.

I'll let you guyz study these for awhile, and mull them over...
 
Putting it all together.
These 4 pics are from the first pressure readings in posts 76-77.
The side filter's paper sleeve is in place.
XS1B-OilPressures03.jpg XS1B-OilPressures04.jpg XS1B-OilPressures05.jpg XS1B-OilPressures06.jpg

These 2 pics are snapshots of the 1st video, cold start part 1.
The side filter's paper sleeve is in place.
XS1B-OilPressures07.jpg XS1B-OilPressures08.jpg
 
These 2 pics are snapshots of the 2nd video, cold start part 2.
The side filter's paper sleeve has been removed.
XS1B-OilPressuresNoFilter-OldOil1.jpg XS1B-OilPressuresNoFilter-OldOil2.jpg

These 2 pics are snapshots of the 3rd video, cold start part 3.
The side filter's paper sleeve has been removed.
Oil was changed, fresh Valvoline 20w-50.
XS1B-OilPressuresNoFilterFreshOil1.jpg XS1B-OilPressuresNoFilterFreshOil2.jpg
 
What a mess, huh?
Collect and tabulate the readings:

OilPressuresCompare02.jpg


I won't bore folks with all the math, which involves approximations, secret sauce, lettuce, cheese, pickles. But, from all that gobbledygook, I was able to determine that the pressure drop across the paper filter sleeve is about 25% of the pump's pressure. In other words:

If the pump pressure is:
40 psi, then the pressure drop across the paper filter sleeve is 10 psi
30 psi, then the pressure drop across the paper filter sleeve is 8 psi
20 psi, then the pressure drop across the paper filter sleeve is 5 psi

This means that at pump pressures above 55 psi, there'll be at least 14 psi across the sleeve, which would open the bypass valve.

In colder conditions than my tests, and with the high-volume pump, it is likely that the pump could hit those pressures and blow the bypass valve.

In cold conditions, with a stock oil pump, the pressures should stay below that threshold, unless the rider revs the engine up.

It appears that, once oil temps get above 80-90°F, the oil's viscosity thins enuff to prevent these high pressures, and the bypass valve is a non-issue. Unless the filter's dirty, or clogged.

Of course, this is all based on my ol' XS1B, with Valvoline 20w-50.

YMMV....
 
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Hey, dps650rider! It's definitely worthwhile to me, I'm keeping it.

I get no noticeable tappet clatter at all, until things get hot, viscosity thins, but that clatter is much less than before. Not so much an RPM thing, mostly about hot, thin oil.

There's another possible source of clatter that I'm investigating, and that'll be in another exhaustive thread...
 
I remember XSJohn (RIP) making some top end mods to improve oiling that made a lot of sense especially when you consider the clatter and wear on the valve stems with stock tappets. Seems like a bigger pump should do the trick too and the comments on this thread support it.
 
Since my opinion is subjective, and I really have nothing to compare to, thought I'd try to capture the sound of my top end clatter, at hot idle. Hope you can hear this.


I'd be curious to know how this compares to others, especially the 'elephants foot' crowd.

I can't hear clattering while riding, unless I crouch down alongside the gas tank.

I can't decide whether to pursue altering the front oil tube restrictor. That may come later, during the hot summer...
 
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A Critique? Awright!
I hear an overhead valve, aircooled engine idling. There is the sound of rockers and valves doing their jobs, some soft clatter as the clearences are taken up emanates from various aluminum cooling fins, each lending its own resonance to the soupy mix of oil, and whirring bearings. Around the front we can discern the cam chain slipping along its guides, abruptly changing direction with the sprockets and doing it all again. Sounds to me like a strong, healthy motorcycle.

Once upon a time I decided that there could be too much side clearance for the rockers. I got some shim material from a machine shop, cut some shims with a drill press clamping the material between two pieces of heavier stock and drilled out the middle, then snipping 'round the outside. It was very quiet after that. Then a local engine builder told me that they build huge drag racing engines with tons of side clearance and it doesn't bother anything. Triumph used to use coil springs on their rocker shafts to keep things snug and quiet. Could these things bind? Maybe, if they are too tight. Are big clearences advantageous to oiling? Could be. I eventually pulled the shims out and never looked back.
 
Spockwerks said:
A Critique? Awright!
...Sounds to me like a strong, healthy motorcycle...
Click to expand...

Oh, it's pretty wore out. 25k miles. It was a non-running dilapidated junker when I got it. The camchain is seriously stretched, more than 10° retarded (at the crank). Overhaul soon.

Spockwerks said:
...too much side clearance for the rockers. ... cut some shims... It was very quiet after that...
Click to expand...

Now, THAT's interesting! I have some camcovers here for a future project, and your shim experiment adds credence. What I've found is sloppy rocker shaft fits in the camcovers, accompanied by "difficult-to-remove" rocker shafts. That ain't supposed to be! Subject for a future thread...
 
I have a Mikes oil filter/cooler on my bike and use KN-112 filters. Does anyone know at what pressure the relief valve opens on these?

Been searching for it but so far no luck.
 
Thanks TwoMany! So that's 4 PSI higher than a stock filter which gives a little more margin before it opens. Sounds like a non-issue as long as I let it warm up some before riding.

Really, even if the bypass opens a bit when cold the oil still has to go through the sump screen which is way better than nothing. Probably not much worse than a stock filter...
 
The new oil pump arrived on Friday and appears to be very well made. Today I checked the clearances, 0.0015 at the tips of the inner rotor, 0.0025 side clearance for the outer rotor and 0.002 side clearance for the inner rotor measured with a feeler gauge and a flat. Might try and install it this afternoon.
 
Got the pump installed today. took a bit of material off the pump housing for clearance to the case, was easier than modifying the case. Also took some 400 grit to the shaft. It measured about 0.0005 bigger than the original making the gears a very tight fit. Would have been difficult to get it apart later without doing this.

Now all I need is some warm weather...
 
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