Does any one know  how the output shaft needle roller bearing is lubricated.

I cannot see where it gets its oil from.

Although this is part of my output shaft " journey",  I thought to keep it seperate.

Hope someone can enlighten me 

Bob

If the oil is fed from the groove, the location of the hole doesn't matter, that's why the workshop manual doesn't mention it. So don't worry about its location. I might have to edit a lazy mistake out of my previous post on your other thread,  prob on the weekend.

Did you look under the bike, where the bearing goes?

Hi Daveyson.

The groove has to have an oil supply to feed the rollers.

I did see an k100 oil path diagram, but although it shows the route through the shaft, it didnt or was not clear 

enough to show a path for the needle bearing.

There are no oilways from top or bottom sump housings.

I am sure it must come from the pump and its dog drive gear somehow , and then down into the area between the 

dog drive and the bearing.but I cannot see how.

Given the speed this thing rotates, I would have thought it would be more obvious..

I need to find a better diagram.

Bob

I found this on the BMW k100 RT web page,

and its seems to suggest the bearing is lubricated by splash feed from oil dropping down onto the sump.

The engine lubrication system is a semi dry-sump type in which oil is contained in a reservoir formed by the crankcase lower section, thus minimizing the heat build-up and frictional losses that would result from major engine components running submerged in oil. The gear-type oil pump, mounted in a single assembly with the water pump and driven off the forward end of the engine output shaft; draws oil through a mesh filter set in the pick-up and forces it through a full-flow filter element into a main gallery. From here it is fed to the crankshaft main and big-end bearings and into the camshafts, which are hollow but plugged at their rear ends so that oil is positively supplied to all camshaft bearings and then out on to the lobes and cam followers; a supply is also taken from the camshaft gallery to operate the hydraulic cam chain tensioner. The teeth of the crankshaft/output shaft primary drive gears are lubricated by a supply passed through the output shaft itself. All other components are lubricated by splash, the surplus oil falling down into the crankcase lower section. Oil pressure is controlled by a plunger-type relief valve set in the pump housing and a bypass valve in the filter ensures that the oil supply is maintained even if the filter is clogged through neglect, to the point where it cannot pass sufficient oil for the engine's needs. If pressure difference exceeds the set amount, the bypass valve opens and allows unfiltered oil to circulate around the engine. A pressure switch set in the pump housing causes a warning lamp to light in the instrument panel if the oil pressure is dangerously low.


Does anyone else have any thoughts on this


bob

@audibob wrote:I found this on the BMW k100 RT web page, and its seems to suggest the bearing is lubricated by splash feed from oil dropping down onto the sump.

That is credible, especially when there is no evidence of bearing failure.

When involved in projects this complex that have a uncertain outcomes, I sometimes must combat a compulsion to spend excessive time in the understanding of tangential or even irrelevant details. What this diversion of focus accomplishes for me is a delay of reassembly and subsequent discovery that all the effort served no remedy for the condition.   It also delays the coming to grips with making a decision either to repeat the disassembly, or figure out where to look next.

More often though, I depend on ear plugs to avoid the struggle altogether.

I must admit it was a case of intrigue more than anything else, as you can normally see an oil path.

As for splash feed I am not convinced,  the oil would have to come in sideways to get to the bearing.

I still think it comes from the pump area area somehow, so unless someone has a 3d printer to make a see through

sump housing we will never know....

The rebuild begins tomorrow anyhow.

As you say, it worked before.

Yeah maybe it does come in sideways,  from the bearing in front of it,  which would be pressure fed, as there seems to be a gap in between. You should see a gallery for the front one.

the oil pump has a path to the inner shaft of the small gear ...and the inner part of the large gear
this lets oil at high pressure side lubricate the shafts in the oil pump housing ...obviously at a loss rate depending clearances

further output of this pressure is presented at the outer bearing surface of the output shaft front roller ....so it flows through the bearing , captured in the sump - crank union
dont forget that there is a small o ring in the small gear inner , as a retainer and seal to prevent oil traversing the inner core of the output shaft , directing the oil to- through the roller bearing , after which falls to the sump

hope that helps ?

Thanks Charlie, 

That removes all doubt. I'll delete my wrong guess from the "output shaft questions" thread.

I could not see any other way for the bearing to get its feed.

It obviously works but I would have expected to see a shallow cut across the bottom dog drive bearing block, to

allow oil to drop into the area next to the bearing, but hey ho it works.

Thanks charlie99