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Oil Pressure Experiments - 2009 KLR650

130K views 479 replies 17 participants last post by  pdwestman 
#1 · (Edited by Moderator)
Guys, thank you all so much for the work you've done to date. It's a great amount of knowledge, experience, testing, and data. Really quite impressive.

I am referring to this thread:

A question for those at the edge of discovery on this oil delivery/efficiency thread...

I've read a large deal about enlarging the orifice on the banjo bolts... but how effective is this when continuing to use a oil delivery line of such a small diameter and significant length and multiple bends? Won't the oil tube need to be larger at some point so that the oil flow isn't restricted by the small diameter of the line?

Just trying to think through all of this along with the rest.

Thanks for any thoughts.
 
#2 · (Edited)
Motosapien -

Thanks for joining in, and you bring up a good question and thought.

We have to briefly revisit the intent of all this - Paul's theory (if I may state it) is that there's too much oil for the oil control rings and bleed holes to accommodate, so KLRs burn oil when turning much over 5000rpm. All his work is focused on reducing the amount of oil going up under the piston. Early on, that was done by re-directing the oil to someplace (the transmission and cams) where it would do no harm and might be of some help.

More oil going to the cams is a good thing, but won't save the head of the engine runs out of oil. More oil sent to the transmission is a good thing and may help with the splash lubing of the upper balancer bearing.

Oil was redirected to the transmission and cams by removing the restrictions in the banjo bolts such that the bearing clearances became the control orifices, not the banjo bolts (edit: though, if I have it through my thick head yet, there is still some control at the transmission banjo bolt - only one orifice of .125").

A larger, straighter, oil line could further help with that by reducing turbulence, friction and so on, so let's take a look.

First, the inside diameter of the oil lines is .160". A banjo bolt with .125" cross drilling has a total cross section greater than the oil line.

The oil line is fed from the filter via the passageway and hole shown below:


The area of the .230" hole is .04"^2, while the area of the passage way (.115" x .235") is .03"^2. There's a corresponding passageway in the case that's probably the same, so the total cross-section of the passage way is .06"^2, which is larger than the .230" hole's area.

This is the mating passageway in the case:


I don't have a case to measure, but the matching oil passage looks like it is also .230" diameter. I'm also not able to confirm that the hole that mates to the .315" hole on the clutch cover is truly blind, but the oiling schematic doesn't show it going anywhere.

The banjos look like they could be made to accommodate a line that had a larger inside diameter; how large I don't know. 1/4" i.d. x 3/8" o.d. might be pushing it, but let's assume.

The banjo bolts have a M10 thread and a .160" diameter bore. To safely go to a larger bore would require going up to M12 banjos and (edit) bolts and there is probably room to re-tap the ports to that size.

As a side note, I've installed a sensor in the test port bolt to get oil temperature. That bolt is also M10, and I tapped it M6 to accept the sensor. It makes me a bit nervous, as the difference between the M10 minor diameter and the M6 major diameter is just a millimeter. It will stay in there for testing, but I'm not sure if I'd trust it long-term. I think increasing the bore and cross drill on an M10 banjo might not be a good idea. Better to go bigger.

All in all, quite a bit of work would need to be done, but it is possible.

Tom
 
#4 · (Edited)
Jeff-

If I understand correctly, that's what's going on now. I want to emphasize that I've kind of stated it, above, from my perspective looking back over Paul's journey through this.

Any research that's gone on for a few years is going to have twists and turns in it. And, as one thing leads to another, a discovery of a real difference in how oiling is treated so differently in early versions of the same bike (not to mention other Kawasakis of the same vintages) leads to questions like 'why?'. That, in turn, leads to how to improve oil pressure at the end of the pressure line which leads to newer ideas about oil burning (can I afford to take oil from the crank? Hell, yes, it's built like a two-smoke and they ain't even got oil except for what's in the gas! Probably has too much oil anyway. Hey! Might be why it burns the stuff!). To me it's the sign of a very inquisitive and sharp mind, one that's good at seeing dots and connecting them.

My visit confirmed that and I'm really interested in where this goes. There's so much 'why' and 'how' in this thread! It's sort of 'out there' but who the hell has done anything new to a KLR in the past 10 years? ;^) I'm thankful to Paul for having brought it up and shared. Isn't it nice to have a thought provoking topic other than the 'Standard Six KLR650 Forum Topics'?

You wanna see a relief valve pop off? I know I'm a bit of an odd duck, but this just struck me as funnier than heck. (This is just a stub of a video that might get edited into a larger story. Might not, too.)




Tom
 
#33 ·
Jeff-

If I understand correctly, that's what's going on now. I want to emphasize that I've kind of stated it, above, from my perspective looking back over Paul's journey through this.

Any research that's gone on for a few years is going to have twists and turns in it. And, as one thing leads to another, a discovery of a real difference in how oiling is treated so differently in early versions of the same bike (not to mention other Kawasakis of the same vintages) leads to questions like 'why?'. That, in turn, leads to how to improve oil pressure at the end of the pressure line which leads to newer ideas about oil burning (can I afford to take oil from the crank? Hell, yes, it's built like a two-smoke and they ain't even got oil except for what's in the gas! Probably has too much oil anyway. Hey! Might be why it burns the stuff!). To me it's the sign of a very inquisitive and sharp mind, one that's good at seeing dots and connecting them.

My visit confirmed that and I'm really interested in where this goes. There's so much 'why' and 'how' in this thread! It's sort of 'out there' but who the hell has done anything new to a KLR in the past 10 years? ;^) I'm thankful to Paul for having brought it up and shared. Isn't it nice to have a thought provoking topic other than the 'Standard Six KLR650 Forum Topics'?

You wanna see a relief valve pop off? I know I'm a bit of an odd duck, but this just struck me as funnier than heck. (This is just a stub of a video that might get edited into a larger story. Might not, too.)

http://www.youtube.com/watch?v=P2bNIN8MQnI&list=UU78339yu0hhASK9JRB6xg_Q


Tom
Guys,
I only used ONE grade of valve lap Compound, one Ace Hardware steel ball (7/16th") if I remember correctly. A piece of vinyl or rubber fuel hose, cut at a slight Angle, for a lap stick.
Part of the 'secret' to lapping is NOT to use MORE compound!
But instead, REUSE what is already on the parts!

The angled cut on the fuel hose, continually 'TURNS' the ball.
The 'Re-use' of the compound, gets Finer and Finer.

Either way, will work!
Just SAVE the Original Ball for Final assembly.

I did use a 'regulated-continuous' air supply and a 'Dial indicator' thru the HOLE, in the Preload Washer to check 'Un-Seating Pressure'.
 
#5 · (Edited)
Hahahahh!!
So did I ever mention what I did for a living before I became a Machinist?? I was an Industrial Valve Technician specializing in Safety Relief Valves for 17 years!! You should hear that style of valve (ball seated) go off at 25oopsi on air!!

Good job Tom!! You have that one working fine!! On straight oil it won't pop open though. Once it reaches the set point it will open in proportion to the overpressure gradually. More pressure more flow.
Best Regards....justjeff
 
#6 · (Edited)
...On straight oil it won't pop open though. Once it reaches the set point it will open in proportion to the overpressure gradually. ...
Jeff -

Can you explain that? That manifold is filled with oil, and I understand the valve should remain open if there is a flow of oil at 70psi, and if the pressure is greater that it will open more fully. I can't put flow through it, but the test is valid for the opening point, isn't it?

Are we saying the same thing? I have been a Relief Valve Test Technician for all of about an hour and half. ;^)

Tom
 
#7 ·
Yes Tom you have found the setpressure, the initial opening point. If the pressure were to increase (cold oil start) the valve would open more and relieve more oil keeping the pressure within reasonable/safe limits.

Some oil relief valves on engines open at a much lower pressure and flow all the time. That would be an oil bypass relief. They may open at say 30 and constantly flow keeping the pressure at say 50 and allow no more pressure rise above say 70.

You are getting a pop on your test fixture because you are using a compressible fluid (air) to pressurize the oil in the header.
If you rigged the relief valve to an oil pump of sufficient volume with a manual bypass valve on your header, You could start the pump with bypass open, gradually close the bypass and see the true action of the valve. It would reach the setpoint, open slightly then gradually open more with the increase of pressure as you continue to close the bypass valve.
As is your rig does not have sufficient flow to see the true action of the valve.

What you are doing is fine and I am impressed you got such a good seat seal with such coarse lapping compound. We regularly went to 1000 grit compound lapping just as you did, using a new ball on final assembly.
jj
 
#8 ·
I gots coarse and fine Clover valve compound I bought in 1974 for lapping valves on my Corvair...

Dats it.

The oil and ball seemed to seat things in. It leaked a bit with just the fine compound. There was some hilarity the first time it popped like it should. I didn't know about throwing a towel over it.

Tom
 
#9 · (Edited)
Bahahahah!!
I was oil testing a 4 inch valve at 2500psi one time and didn't get all the air out of the manifold. The boss wasn't happy about me painting the wall with hydraulic fluid 40 ft away.:t1202: I'd send you some 800grit but it comes as a dry white powder and I'm not sure about sending it in the mail to you!
What is your household water pressure? More than 70psi? If it is you could flow test the valve that way. Not that you need to. The viscosity difference has no significant effect on the operation of this style of valve but your CARBON STEEL BALLS may RUST so be sure to apply oil after the water.
jj
 
#11 ·
Nope, late dinner here tonight.

House pressure is 100psi. In honor of our drought, I think I won't hook the valve up to the garden hose.

Once all is said and done, I may take a leaky one and make a lawn sprinkler out of it...

Tom
 
#12 ·
I have found it is easier to control the pressure by closing a bypass(outlet) valve to increase the pressure rather than to open an inlet(supply). You can set it up either way.
Regards....Jeff
 
#13 ·
Nice job, Tom however it was a disappointment not to see the first director's cut showing the oil spray. ;-)

I included that in an ABS modulator thread on another group at several points as: "Clean glasses as in step X".

I haven't gotten to lapping my relief valve as yet but seems like a no brainer if one is willing to spend the time.

Justjeff, given your professional exerience in this field, can you see any downside to lapping (improving the seal) of the relief valve?

It seems to me that It's unlikely that a small relief valve leakage will affect the operation under any but the most remote possibility so not likely likely to make any significant improvement. That said, no down side to if one feels like doing so....

Do you agree that this is an accurate view?

Tom, you commented regarding the bottom end being essentially like a two stroke and it certainly resembles those systems excepting for two factors which have been at the root of my concern from the outset:

1) The wrist pin does not have a bearing and runs directly in the steel of the connecting rod which means it requires both much more lubrication and cooling than a typical two stroke.

2) Piston cooling is highly dependent on oil spray from below onto the underside of the piston crown. None of us has been able to offer any means of evaluating the effects of reduced spray on piston cooling in this engine. IME, pistons reach a critical temperature after which they fail in a rapid progression.

Two cycles depend on the inlet charge for piston cooling which must be considered in design.

This has been a very interesting project and Paul has shown great courage in taking the risk of long distance trial.

There are many not qualified/not measured factors involved such as oil flow, for example. No one has been able to offer data or calculations indicating the effects of cross drilling the banjo bolts, for example. It is not unlikely that the cross drilling had no material increase in oil flow because the size of the cross hole may not be a materially affecting factor. That the cross hole is at 90 degrees to the axial bore will cause significant restriction, for example.

We don't have any indication as to the relative restriction offered by the long axial passage in the banjo bolt. It is quite possible that the longer axial passage has so much more resistance to flow that the cross hole size is immaterial. Someone pointed this out a while ago, again.

We have no indication as to whether the banjo bolt is a restriction factor at all, given the length of the oil pipe, so it may be that our drilling of the cross holes in the banjo bolt has no real effect on oil flow.

One would need to set up a test jig in order to attempt to duplicate the pressure drop across the various parts of the system as a means to evaluate these effects. If one has an oil temperature, same oil, and pressure at both ends, one should be able to calculate the oil flow rate, Correct, someone? Anyone?

Regardless of calculations, if one knows the pressure difference between the inlet and outlet of the oil pipe (for example) one could use the same oil at the same temperature with an adjustable oil flow to duplicate that pressure difference. Say, for example one had 5 PSI difference between the two ends, applying 5 PSI at the inlet should allow one to measure the oil flow rate. Knowing the oil flow rate/volume would allow one to experiment with changing the banjo hole size and so on to determine changes in oil flow.

I never did find a donor valve cover into which to glue windows to study oil throw-off from the cams and am into other interests but some time.

Too many unknowns and far to many assumptions here, IMO. We just don't know many of the things which are claimed.

What we do know is that Paul performed these several modifications, reported the data. We really don't know the import of the data other than we do know that Paul's bike made a long journey successfully, he reports improvement in oil consumption and fuel consumption which may not actually be due to the factors which we believe.

I'm convinced that the results and conclusions he reports are correct because they seem to be well documented and there is no doubt in my mind that he has reported accurately. When I state "accurately" I mean that he has professional competence to evaluate that the information reported is correct as reported. In other words, he has not made errors in terms of what he has done during the work. Very professionally done!

The apparent reduction in excessive oil throw-off, as I stated when first commented on this project, would be expected to have the results reported because we used to see these effects as common place in automotive engines when worn main bearings were encountered. We also saw oil consumption increase in engines which were fitted with a high pressure oil pump rather than a high volume pump. Both worn mains and higher pressure will/must increase throw off of oil onto the cylinder walls.

I am not convinced that the case has been made that cross drilling of the banjo bolts does increase (materially) the oil flow volume to either cams or transmission. As said, it seems like a no-down side as it may increase this flow which would seem not to be a bad thing. Paul's work is, I think, conclusive in showing that were flow to cams and transmission to be somewhat increased, this increase will not be likely to reduce the crankshaft oil flow to a problem degree.

Great stuff and much to think about however we do need to be careful in what conclusions we are willing to accept as proven.

Perhaps Justjeff may be willing to comment on flows and restriction effects?

Good on you, Paul. You do have a large set of coconuts for trying that long distance ride. I don't think I'd like to play chicken with you. :) I'm certain that others also are very appreciative of the risk which you took in order to offer the outcome.
 
#14 · (Edited)
It seems to me that It's unlikely that a small relief valve leakage will affect the operation under any but the most remote possibility so not likely likely to make any significant improvement. That said, no down side to if one feels like doing so....
As I have reviewed Paul's theory, work, and results my conclusion is that they, at the very least, do no harm. The leak rate on any given valve may be great or small, but it would seem that the small amount of work involved in stopping the leakage is time well spent. There's not much sense in having the pump merrily spinning away only to have some of the oil dumped straight back to the sump.

Tom, you commented regarding the bottom end being essentially like a two stroke and it certainly resembles those systems excepting for two factors which have been at the root of my concern from the outset:

1) The wrist pin does not have a bearing and runs directly in the steel of the connecting rod which means it requires both much more lubrication and cooling than a typical two stroke.

2) Piston cooling is highly dependent on oil spray from below onto the underside of the piston crown. None of us has been able to offer any means of evaluating the effects of reduced spray on piston cooling in this engine. IME, pistons reach a critical temperature after which they fail in a rapid progression.
Yet there is one notable condition that doesn't exist in a two-smoke and one notable observation.

The KLR has a sump and the environment in the crankcase is extremely oil-rich. In the event of a piston ring failure one can expect a tremendous amount of oil to be blown into the air box, as Trundlebike saw with his double land failure. The wrist pin has concerned me, too, but I honestly believe that there is a whole bunch of oil floating about in the crankcase that should be sufficient.

The underside of a typical KLR piston is typically very clean with no varnish. To me that indicates that there is no cooling problem in there. Paul hinted that he thinks that his improvement in fuel consumption might come from the piston being just a tad hotter and therefore contributing to more efficient combustion.

There are many not qualified/not measured factors involved such as oil flow, for example. No one has been able to offer data or calculations indicating the effects of cross drilling the banjo bolts, for example. It is not unlikely that the cross drilling had no material increase in oil flow because the size of the cross hole may not be a materially affecting factor. That the cross hole is at 90 degrees to the axial bore will cause significant restriction, for example.

We don't have any indication as to the relative restriction offered by the long axial passage in the banjo bolt. It is quite possible that the longer axial passage has so much more resistance to flow that the cross hole size is immaterial. Someone pointed this out a while ago, again.

We have no indication as to whether the banjo bolt is a restriction factor at all, given the length of the oil pipe, so it may be that our drilling of the cross holes in the banjo bolt has no real effect on oil flow.

One would need to set up a test jig in order to attempt to duplicate the pressure drop across the various parts of the system as a means to evaluate these effects. If one has an oil temperature, same oil, and pressure at both ends, one should be able to calculate the oil flow rate, Correct, someone? Anyone?
Unfortunately, what you request is too hard to accomplish. If all of this is Bachelor's thesis, your suggestions would be at the level of a PhD dissertation. One would need a decent flow meter or be willing to measure how far a stream of hot oil squirts, as well as some machined fixtures to set the oil tube in and some sort of pump to circulate the oil. Might want a heater, too. Were one to go to all that trouble, why not measure flow instead of calculating it?

All that I have to go on is empirical evidence from Paul's data, coupled with some marginally educated intuition.

When the oil hits the banjo it runs smack into the bolt, has to go around it, swirls around for a bit, and finally decides the path of least resistance is to gown the 1/16" diameter rabbit hole.

Stranger things have happened, but it would seem that increasing the hole to either a single .125" hole or double .125" hole would not reduce flow.

As to the axial hole being restrictive, once the oil gets in there it would seem that it would be no more restrictive than the oil tube itself. They have the same inside diameter.

Sometimes all we have to go on, without going to unreasonable efforts, is "try it and see". Modify, test, observe, and report. Draw conclusions and see what they suggest you do next.

Tom
 
#16 ·
Norm -

Pepper The Laser Weiner Dog and I just returned from driving about town on a series of errands.

All the while I was mulling this flow thing over. Mind you, if I thought I had the required stuff in the Shop of Horrors, and really knew what I was on about, I'd have done this.

First we have to define a question to be answered and then design an experiment to answer the question.

If the question (and please feel free to restate the question) is "Does installing a different set of banjo bolts improve the flow to the transmission and the cam?", then how about these possibilities for an experiment?

Get a pump like this one which is supposed to provide 70 psi and 23 gal/hour (.5mpa and 90l/hr).

Rig up an oil line and plumb the pump to the center banjo, feeding the pump from a gallon jug. Install banjo bolts at the cam and transmission banjos. Position large beakers under the banjo bolts. Turn the pump on and record the time to fill the first beaker, then calculate flow rates for both banjo bolts. Repeat with the banjo bolts with the larger orifices.

Would that answer the question?

Or should a pair of orifices be attached to the banjo bolts that simulate the bearing clearances? That is, if the bearing has a diameter of 25mm with and a clearance of .038mm we can calculate the area of the clearance, multiply by the number of bearings feed, and build an orifice of that diameter. Again, catching the flow in a pair of beakers and recording the time to fill.

Would that be necessary to answer the question?

Either one of these experiments could be economically done and I'm dumb enough to try it.

Is recording the pressures important (it complicates things quite a bit - fittings and all that)? If so, where? I have a minimal collection of gauges - 0-30, 0-60, 0-300. Measuring pressure, then, is like peeing into a cash register - it runs into money, because I'd probably have to come up with a couple more low-pressure gauges.

What do you think? Not quite doctoral candidate stuff; more like a special project for the fluid dynamics professor.

Tom
 
#17 ·
It would be really interesting to learn whether there is actually more oil flow to the cams and transmission due to increasing the banjo bolt size.

The obvious question on the table, however is: "Does increasing the oil flow to the cams and/or the transmission produce a benefit?"

There were some assertions posted to the effect that increased oil flow to the transmission would be likely to increase the life of the rear counter balancer bearing but I am unable to accept this conclusion without hearing the case in support. To conclude that the bearings which do fail are doing so because of insufficient lubrication is, IMO, unsupported. Bearings have a service life but taking the variations within a large bearing sample, that life varies to an amazing degree. SKF and other bearing manufacturers used to publish mean service life in hours for a given bearing, operated under a given load, at a given speed. Anyone who has studied bearing engineering to any degree will be aware of this information.

I think the case is at least equally strong in support of the posit that these failed balancer bearings may be mainly due to individual bearings at the lower end of the service life. One can see this on paper by simply consulting the bearing manuals while the posit of bearing failure due to lower oil supply does not explain why the other thousands of KLR's manufactured and operated in a similar way show these bearing failures as extremely unusual.

We may be chasing a tail-less dog by intending to improve operation by increasing oil flow when there seems not to be a problem.

I'm always interested in investigation, especially when someone offers to do all the work. ;-)

As Michael Caine said in the movie Zulu: "No trouble old chap! I wasn't offering to do it myself."

As to modelling, the problem I see with calculating the orifice size to simulate the cam bearings, is that this adds more assumptions to the mix. I'm of the opinion that it would be better to measure the pressure at the head banjo and at the engine case banjo. If one has these two numbers and your suggested adjustable pump, one could heat the oil to average operating temperature and use a small valve at the cylinder head banjo.

Pump the oil from the pump through the engine banjo at a pressure matching the engine operating pressure and adjust the valve off the head banjo to obtain the same banjo pressure as when the engine is operating.

Same oil, same temperature, same inlet pressure, adjusting to same outlet pressure should produce the same flow volume as in engine operation. This will also allow the inlet pressure to be adjusted if required to maintain the fixed pressure which will reduce the variations.

Once one has the pressures and volume, one could drill the banjo axial hole and cross drilling to test. The results should be obvious as same pressure at inlet which results in reduced pressure at outlet banjo must indicate lower restriction in the banjo. Each banjo could be tested separately as one might expect that the drilling of the inlet one will better support increased flow since the inlet banjo supplies both outlets.

I think my initial set up would be to couple the adjustable pump to the oil pipe right on the engine in order to produce a valve setting for the transmission outlet also. A problem which needs be accommodated is that there are two outlets and one inlet, making a modification to one outlet likely to affect the other.

I will have to think about this a bit more but think one should be able to use the transmission banjo as the pressure sample point as Pascal's Law should be close enough given that there will be not flow in the transmission branch if testing in this way.

We used to have an electric motor powered oil pump in most machine shops to prime engines prior to first start up. It was really interesting but very messy to run something up to full oil pressure with the oil pan off.

I'm thinking that regulating your pump's oil pressure should be simple enough with a shunt valve back to the oil supply container?
 
#19 ·
Tom posted, "I'd have to guess that in a testing environment the test would end only because the world had run out of gas." Laughing my head off! Good assessment.

Reminds me of Christopher Hitchens response, "Im willing to try anything once, except incest and Scottish dancing."

I'd think that a 10 weight oil or even ATF would be close enough if you aren't into heating the oil. I don't think heating the oil would be that much trouble but reference back to my Michael Caine quote. ;-)

If you can cut some corners to keep the scope of the project manageable, the outcomes would be interesting and may prove useful with regards to some other facet of operation or diagnosis.

The chip in Paul's banjo bolt was indeed a classic and serves to show how far we run with preconceptions. If one had posted the intent to restrict a banjo to that degree, most of use would, I think, have expected cam bearing failure or at least signs of wear.

That simply points to my contention that we are running almost completely blind in many instances.

I hope this does stay within the manageable range as would like to hear the results. I'm finishing one research project and working on some other modifications so the oiling one is not on my clip board for now.

Best,
 
#20 · (Edited)
Yes, I am trying to keep it within my means and bounds.

Really should get my own thread and quit mucking up Paul's.

I also realize I mis-spoke regarding calculating the orifice to simulate the bearings. It is not the annular area of the bearing, edit: it's twice that (one for each bearing edge), times the number of oil feeds.

This is going to be interesting. I think.

Tom
 
#21 ·
Please PM if I don't find your new thread, Tom.

Paul is remarkably tolerant of tangents from his threads but I agree that this is muddying the waters.

A problem in calculating clearance flow is that boundary layer flow considerations interfere. Playing around with an oil pump, it seemed that the flow from main bearing clearances was less than that expected by simply calculating area of bearing cross section minus area of shaft cross section, and factored by the length of the passage. It really begins to "get out there".



Yes, I am trying to keep it within my means and bounds.

Really should get my own thread and quit mucking up Paul's.

I also realize I mis-spoke regarding calculating the orifice to simulate the bearings. It is not the annular area of the bearing, it's the area of a cylinder that is half the bearing clearance with the diameter of the oil feed, times the number of oil feeds.

This is going to be interesting. I think.

Tom
 
#22 · (Edited)
Very true, but I think I'm not after absolute flow numbers that one would find in the engine, but rather relative flow rates, small banjo holes vs large.

It's better to try and consider it than simply let the stuff spew out of the banjo bolts. Close gets it.

It's horse shoes and hand grenades, eh?

Tom
 
#23 · (Edited)
Problem is that relative numbers are only good when the flow rates/pressure differentials are within the same range. If you have a large orifice in the banjo, for example, but the restriction down stream is quite significant, a change to the banjo orifice will have little effect on flow. That type of dynamic is why I was concerned that the flows and pressure differentials are as similar as possible to the engine's.

I'm certain that you already are on this track so was only mentioning this as an indication of what I was thinking.
 
#24 ·
But the only downstream restrictions are the bearings, which I'm going to try to simulate. After the bearings it all drops to the sump.

Tom
 
#25 ·
Normk andTom:
Am on trip rightnow so comms are compromised. I see no issue with too good a seal on the valve. I don't have the expertise you are seeking re flow rates and restrictions, sorry. Get mod to move these irrelevent posts to a new thread and leave poorpaul in peace!!!:fighting0001: Regards....jeff
 
#28 ·
Part of it was much ado abut nothing (on my part). The total leak edge area on the cams is greater than the area of the banjo bolt axial hole. The transmission leak edges are even larger, as the shafts are larger and there of 12 edges. I just need to let 'em rip.

"Come along, it'll be a great slide", Tom said with an oily tone.

Tom
 
#30 ·
I just used compressed air pressure from a regulated air line, continuous supply, steady flow, checked pressure by airing up a tire and using a digital air gauge.
KLR style, Simple, Cheap and Easy, to quote Norm K.

MY modified relief valve, starts relieving at 22-23 PSI, Limits at 32-33 PSI.
It has a very light spring, almost 'zero' preload.
I had to compress the 'REPLACEMENT' spring in a vise, 'just slightly' and heat the end coils, several times.
I have NO WAY to measure my spring, but it is VERY LIGHT, compared to an original! Might I suggest a quarter of the original strength, squeezed between your finger and thumb.
 
#31 · (Edited)
Tom S. and Norm K.,
Who's off the deep end Now? Just look what I started!

I'll suggest, Keep It Stupidly Simple, KISS!
I tried to.

Try it, if it works, great! Try a little further.

Thanks for the interest Guys.

My bike is still running after Ouray/Silverton CO. Regrettably I did NOT ride it HOME, TOO Sore of Neck. Too Much 'rubber necking' of the scenery!
High 50's-Low 60's for MPG. Mixed roads. Red Mountain pass, several times. Ophire, Hurricane, California, Engineer, Cinnamon, Stoney, Corkscrew.
Great rides, GO THERE!
 
#32 ·
I don't have a compressor, just a bicycle pump.

The copper stuff I had laying around, left over from a plumbing project. The only thing I had to buy was a 1/4 npt to 1/8 npt reducer.

I'm going to leave this valve alone; it's perfect at 70 psi. The second valve I am going to try to set at 35 psi. The ACE hardware didn't have a spring I could even start with, so I'm off to the other hardware store. They might even have 1/16 npt plugs.

Tom
 
#34 ·
Some random questions/thoughts:

1) Tom, just checking in to see if you have had any time to measure banjo flows. etc?

2) Paul, your Honda 50 reference joined a pair of synapses leading to wondering if you have run your modified engine on a dyno? If one had a reference such as intake vacuum at cruising speed, this would allow one to simulate the engine power output at that road speed, while running on a dyno. Since it will require "X" horsepower to move the bike at that road speed, one could then remove the crankshaft oil gallery restrictor and then run at the same RPM & load (horsepower) on the dyno. If the dyno load and RPM are reflected by a higher intake vacuum this demonstrates that the engine is developing more power at the original vacuum level and that it requires less power to output the required power for the given road speed.

In other words, there is less loss of engine power because of the reduced oil throw off.

I would expect this to be the case based on experience with other engines and Paul's reported increase in fuel mileage.

An alternative might be to simply run vacuum road tests without the dyno to show that lower engine load is required to drive the bike at a given road speed.

4) The statement "it's built like a two-stroke" is not correct in some important ways: the wrist pin runs in the connecting rod without even a bushing. This type of bearing requires far more lubrication than does a rolling element bearing such as the needle bearings found in two-strokes of significant power output. A two-stroke depends on intake and crankcase charge for piston cooling which makes them far more affected by piston heating. Different set of problems. I nave no idea how we might quantify the piston/wrist pin lubrication/cooling requirements and effect.

It does seem most likely that almost any significant throw off of oil by a pressure system will exceed 100 or 150:1 two stroke premix so think this is on safe ground excepting for the wrist pin.

Paul's oil analysis doesn't show increased iron levels so it seems that the increased wear (if this is even happening) to the rod and wrist pin is insignificant/unimportant. I'm also comfortable there. What I mean by expressing comfort is not the claim that this is verified as correct but rather that I'm willing to risk on what I also think is the reasonable expectation that the effect is sufficient.

I'm in not way attempting to "throw a wet blanket" on any portion of this project because I think it's one of the most exciting and potentially valid exercises regarding the KLR since the improved doohickey and the Thermo-Bob. Simply picking away in hopes that there is some way to find another window through which to move it further.

At this point I'm so greatly in Paul's debt for the education and entertainment that, were his engine to fail due to the reduced oiling (don't think this at all), I'd send him some money to help with the repair.

I made a tongue-in-cheek query of Paul as to whether he had thought of modifying the oiling to the Honda 50 which he and his buddy had considered riding to Alaska. He hasn't replied as simply joking but one should also consider that there are very, very likely many other machines out there which might benefit from an assessment of the oiling system. That was the real point of the joke.....that it wasn't a joke at all. He's proven that in spades!
 
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