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Exposing Oil Picc-up On Steep Grades


Thunderpaugh

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OK, then, pretend you're a squid accelerating hard from low speed with the bars at full lock. You could be turning accelerating hard to the left, with the bike upright or even leaned slightly to the right, and all that erl slopping to the outside.
Only if he high sides.

 

The forces that keep a bike on two wheels are the forces that keep the oil firmly centered (left to right) in the sump. :nerd:

 

There IS momentary side loading induced at turn initiation (counter steering input), but it is truly momentary so not relevant to this discussion.

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You are assuming the rear wheel does not break traction. If you know how to do it, you can do multiple donuts pivoting around your front tire. A really good rider could do it until the engine seized.
Well, I suppose if you put your foot down ... then yes ... you can lean it over doing donuts. But anyone who needs to put his foot down to do donuts deserves to havehis engine blow. Might just as well put it in neutral, lean it over 'til the head guard rests on the ground, and rev it vigorously in neutral.

 

When i do donuts ... seated upon the handle bar with my feet on the front axle, I find the bike remains vertical during the entire maneuver. Does your experience differ?

 

You see what happens when we pass beyond the sublime ... it's almost impossible to claw our way back from the absurd. I'm done.

 

On a far more somber note ... learned late last night that John-Mark Arechiga is dead. Died Saturday in a warm up for the WERA race being held last weekend at Buttonwillow. He was known hereabouts as "DK" or "drknow." I posted details on the SoCal list. He was a friend to many and I was honored to have him call me friend. http://tinyurl.com/3vpq5e

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That's terrible news Pierre! My sincerest condolences to you and all who knew him. I will certainly miss his posts here.

 

I'd be happy to contribute towards some flowers or to help his family if appropriate. If any of you SoCal guys get a donation fund going please post the information somewhere on this site.

 

Godspeed John-Mark.

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I dunno for sure how steep it would have to be to expose the pick up. If you're getting to the point where its that steep the rear crank web will be throwing a lot of the rearward settled oil about anyway further diminishing that sitting near the front of the sump where the pick-up is. Do remember that the plate DOES have holes in so the oil WILL still migrate rearwards. It's purpose is to slow the rearward movement sufficiently that pick-up exposure doesn't occur in hard acceleration situations be they on a flat surface or a hill.

 

The fact that the plate DOES do this has been independently verified by Greg who gave his bike, which used to regularly expose its pick up, the 'Torture Test' he described in his installation write up. Up a steep cobbled street in Seattle, hard on the gas, and no pressure drop :huh2: I really don't know what I can do to further prove my point. Individual evaluation by a third peer party or parties and repeatable results achieved under a variety of conditions would seem like pretty good scientific evidence and proof to me but obviously I have a hidden agenda and have nothing better to do with my life than deliberately try to make people paranoid about non existant problems.

 

Can I categorically say that in the conditions you've described above there will or won't be pick up exposure? No, I can't. But knowing what I do about the exposure problem I would think that living in that sort of environment is exactly the sort of place where it could be a problem, if not in this exact circumstance then at least on a regular basis.

 

Pete

 

Thanks, Pete. This is not a challenge to the function of the plate, nor to the veracity of your statements about it. I believe it works as stated. I understand how the plate would trap the oil underneath to prevent surging during hard acceleration and wheelies. On a long steep hill I understand how the oil might find its way through the holes in the plate, give sufficient duration of riding up the grade. But that is not the point. I was trying to employ the resourses of the forum and determine from knowledgeable sources if it was possible to expose the oil pick-up on a steep grade. The answer seems to be "yes, if it is steep enough" without the plate fitted, and "yes, if it is steep enough and long enough" with the plate fitted. But it is difficult for anyone to deternine what that grade is, or to advise me regarding conditions they could not remotely know about.

 

While riding up a short but steep grade, I noticed that the oil pressure light was on. (Visiting in the hills of upper East Tennesse, in very wet conditions). After making a turn onto level ground, the light flickered and started to dim. Subsequent erratic behaviour of the oil pressure light, followed by normal light behavior, and then quickly followed by the total faliure of the oil pressure sensor's electrical function led me to conclude that what I experienced on the run up the grade was the oil pressure switch begining to fail, and which maybe was exacerbated by moisture comtamination from the torrential downpour I rode through. But I was still left with the unsettling feeling that that short, slow run up the steep grade could have also exposed the oil pickup, loosing oil pressure in the process, and that the crank bearings took a hit, hence the flickering and lazy oil pressure light behavior. How likely is it that the oil pressure light coming on during the run up the grade was due to both oil starvation (which is questionable and uncertain at this point) and oil pressure sensor failure (which certainaly did occur)?? I have noted your remarks elsewhere that damage to the crankshaft bearings begins with any loss of oil pressure. The light was on for a short period, seconds, but long enough in my opinion for damage to occur, if that's what was happening. However, the bike runs fine, and strong, and there are no unusual noises coming from the crankcase, and no unusual vibrations. Now it seems very unlikely that there was oil starvation due to the steep grade. I was simply trying to find out if it was possible, and if so, how probable, that oil starvation occured, before I take the time and trouble to test the oil pressure to see if I can determine if the is any damage to the crank bearings, or to just remove the rod caps to have a look at the big end shells and rod journal, or maybe both. At this point I am feeling that what I experienced was simply an oil pressure sensor failure. And a hefty dose of paranoia.

 

Thanks, everybody, for all the comments and insights.

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Guest ratchethack

Hm. Trouble is, paranoia often transforms into wisdom after the fact. The world's foremost paranoiac of his day, Sir Winston Churchill, comes to mind. . . :whistle:

 

Seems to me you've got well-founded reasons for concern. But lacking any symptoms of rod bearing failure, your options are:

 

1. Take all due precautions to ensure that oil starvation doesn't continue. To my knowledge, the Roper slopper and a new oil pressure sensor are about the best you can do.

 

2. Have the sump off and rod bearing caps off for a look at the bearings and crankpin, and if needed, dress it up with crocus cloth and fit a new set o' bearing shells (cheap). The downside here is the cost of a set of new rod bolts (not cheap) but recommended by many o' the Pro's, including Pete, once you have the caps off.

 

Now this is just me, but based on my understanding of how tough these old birds' bottom ends are, I'd go with option 1 above, keep an eye on that new sensor indicator light just for peace of mind, and never worry about it again. :luigi:

 

BAA, TJM, & YMMV

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Guest ratchethack
I see what you two are saying in that once you are into a turn, the oil surface stays flat with the sump. But If you countersteer hard to initiate a left turn won't the oil momentarily try to stay on the left side of the sump?

I think Pete has a point.

I reckon if you're countersteering hard enough to expose the oil pickup, you must be stepping out the rear end and power-sliding around flat track style (which I seriously doubt would be a concern in this regard even then) -- or sidehack racing (which very well might). :o

 

post-1212-1210774508.jpg post-1212-1210774524.jpg

 

Other'n that, IMHO any effect of countersteering a Guzzi on the road on oil pickup exposure would be nil. :huh2:

 

But o' course, that's just me. -_-

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Yup, it's possible and in many cases quite easy. The oil pick up is in the front right hand (? this is from memory at 4.30AM.) corner of the sump. Uphill and banking to the left is the most risky. It's a problem that Guzzi finally, obliquely, acknowledged with the launch of the Breva/Griso/Norge motors which have a far better sump design.

 

Yes, there is a cure, but since I'm the one that designed it I always get accused of venal motives and charlatanry when I mention it.

 

Pete

 

Well Pete if you're a charlatan at least I hope you're not a harlot!

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Yup, it's possible and in many cases quite easy. The oil pick up is in the front right hand (? this is from memory at 4.30AM.) corner of the sump. Uphill and banking to the left is the most risky. It's a problem that Guzzi finally, obliquely, acknowledged with the launch of the Breva/Griso/Norge motors which have a far better sump design.

 

Yes, there is a cure, but since I'm the one that designed it I always get accused of venal motives and charlatanry when I mention it.

 

Pete

 

 

Hi Pete, I've send you a pm, about your crappy design rofl.gif . Could you answer me back.

 

Thx

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Thanks, Pete. This is not a challenge to the function of the plate, nor to the veracity of your statements about it. I believe it works as stated. I understand how the plate would trap the oil underneath to prevent surging during hard acceleration and wheelies. On a long steep hill I understand how the oil might find its way through the holes in the plate, give sufficient duration of riding up the grade. But that is not the point. I was trying to employ the resourses of the forum and determine from knowledgeable sources if it was possible to expose the oil pick-up on a steep grade. The answer seems to be "yes, if it is steep enough" without the plate fitted, and "yes, if it is steep enough and long enough" with the plate fitted. But it is difficult for anyone to deternine what that grade is, or to advise me regarding conditions they could not remotely know about.

 

While riding up a short but steep grade, I noticed that the oil pressure light was on. (Visiting in the hills of upper East Tennesse, in very wet conditions). After making a turn onto level ground, the light flickered and started to dim. Subsequent erratic behaviour of the oil pressure light, followed by normal light behavior, and then quickly followed by the total faliure of the oil pressure sensor's electrical function led me to conclude that what I experienced on the run up the grade was the oil pressure switch begining to fail, and which maybe was exacerbated by moisture comtamination from the torrential downpour I rode through. But I was still left with the unsettling feeling that that short, slow run up the steep grade could have also exposed the oil pickup, loosing oil pressure in the process, and that the crank bearings took a hit, hence the flickering and lazy oil pressure light behavior. How likely is it that the oil pressure light coming on during the run up the grade was due to both oil starvation (which is questionable and uncertain at this point) and oil pressure sensor failure (which certainaly did occur)?? I have noted your remarks elsewhere that damage to the crankshaft bearings begins with any loss of oil pressure. The light was on for a short period, seconds, but long enough in my opinion for damage to occur, if that's what was happening. However, the bike runs fine, and strong, and there are no unusual noises coming from the crankcase, and no unusual vibrations. Now it seems very unlikely that there was oil starvation due to the steep grade. I was simply trying to find out if it was possible, and if so, how probable, that oil starvation occured, before I take the time and trouble to test the oil pressure to see if I can determine if the is any damage to the crank bearings, or to just remove the rod caps to have a look at the big end shells and rod journal, or maybe both. At this point I am feeling that what I experienced was simply an oil pressure sensor failure. And a hefty dose of paranoia.

 

Thanks, everybody, for all the comments and insights.

 

That was the symptom mine displayed -- 2004 V11 Sport -- a flicker... a solid light... a flicker and gone. Thought: nah, that can't be anything! But it kept happening. I got worried - and about the same time, Pete made the plates. I bought and installed the plate -- never seen my oil light since - except one time, when I was actually low on oil. I stopped immediately at a gas station and the bike took a full quart... don't know why she was so thirsty and never been thirsty between lubes again.

 

:rolleyes:

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