Rocker arms - sorry guys something to worry about

Boss302 said:

I'm sure this topic has been discussed ad infinitonauseum, but since we
are talking about oiling of the innerds, what is the proper oil level to both avoid oil in the airbox and not deprive the engine of proper lubrication. I added an extension to my dipstick and run the oil level at just the level that would have fallen from the bottom of the stock dipstick. My oil collector bottle from the airbox fills slowly this way. I have the modifications that were supposed to have solved this problem but if I overfill , it still dumps oil. How crucial is oil level in engine lubrication? Is it a small or large acceptable oil volume range? I've reviewed the oil flow path information. I guess proper viscosity is also very important.

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Unfortunately, with the 961, the oil level depends on the bike and the dipstick. Really as long as the oil pump is constantly fed oil during any riding condition, you can play with what oil level works for your bike. Again to repeat. If the oil isn't flowing properly out of the oil tank then you can get a false reading. If the inline filter is clogged it will slow the flow of the oil out of the tank making false oil readings as well as creating an overfull condition.

BritTwit said:

Sorry to beat this topic to death but I'm not clear on what you are referring to as the relief valve.
Where is this valve located?

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Have a look at this thread. The valve in question is actually an anti wet sump device, but the one Norton fit has a tiny aperture of maybe 3mm.
Ollie‘s version it much larger, but the crankcase needs to be tapped to install it.


It is doable with the engine in situ, but as you’ll see you need shortened taps.

cliffa said:

Have a look at this thread. The valve in question is actually an anti wet sump device, but the one Norton fit has a tiny aperture of maybe 3mm.
Ollie‘s version it much larger, but the crankcase needs to be tapped to install it.

961 Birthday

Valve guides are cast iron, no appreciable wear on them or the valve stems. Rocker bushes - these were easily removed, and i am told could be reinserted with hand pressure :oops:. Must have been very close to the rockers turning on the bushes rather than the bushes turning on the spindles. Ollie...

www.accessnorton.com

It is doable with the engine in situ, but as you’ll see you need shortened taps.

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Cliffa,
Makes sense.
Thanks.

Here’s some pics from my install..

cliffa said:

Here’s some pics from my install..

WTF now

So yesterday afternoon I spent a pleasant afternoon finishing off my winter refresh. The last item was to install Ollie's improved oil non return valve. Member ntst8 had very kindly loaned me his specially made M17 taps. Apparently the valve can be installed with the timing cover in place, but I...

www.accessnorton.com

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Pretty slick job.
So the pressure relief valve vents the oil from the oil filter chamber to the timing chest, then down thought the hole into the sump?

BritTwit said:

Pretty slick job.
So the pressure relief valve vents the oil from the oil filter chamber to the timing chest, then down thought the hole into the sump?

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This is not to be confused with the over pressure relief valve which is within the oil pump itself, it’s a one way anti wet sump valve which stops oil seeping past the oil pump when the bike is not in use and all ending up in the sump - a common problem with dry sump bikes. @Stu Bodycote posted a picture of the tiny wet sump valve Norton retro fitted to the pressure side of the pump ( which I removed), but I can’t find it at the moment.

EDIT,

found it..

The one below Stu’s thumb is the over pressure relief valve.

Boss302 said:

I'm sure this topic has been discussed ad infinitonauseum, but since we
are talking about oiling of the innerds, what is the proper oil level to both avoid oil in the airbox and not deprive the engine of proper lubrication. I added an extension to my dipstick and run the oil level at just the level that would have fallen from the bottom of the stock dipstick. My oil collector bottle from the airbox fills slowly this way. I have the modifications that were supposed to have solved this problem but if I overfill , it still dumps oil. How crucial is oil level in engine lubrication? Is it a small or large acceptable oil volume range? I've reviewed the oil flow path information. I guess proper viscosity is also very important.

Click to expand...

Assuming you do not run the oil low enough to starve the engine, then the biggest issue with running reduce oil capacity is heat.

One of the primary purposes of an external oil reservoir is to allow the oil to cool before being returned to the engine.

Air cooled engines give their oil a hard time with heat anyway, therefore reducing the reservoir capacity will make this worse.

So if you choose to run a lower oil level, you’d be well advised to increase your oil change frequency.

Norton reduced the oil quantity by around a litre. I expressed the same thoughts as Eddie.... naturally I was ignored lol

I would rather have the anti-drain back valve where Norton put it (in the oil pump) . As my bike is set up now , I can run 2.0 liters of oil with out spit back discharge . This is oil level to the top of the new longer stick knurl section. This has been fully tested at interstate speeds for hundreds and hundreds of miles . If you have lots of steep down hill with hard braking you are bound to have more issues as the oil will slosh up to the vent in oil tank . Some bikes may have a slightly different oil tank volume . With out an air box , there is plenty of room for oil capacity increase , say additional oil cooler or aux oil tank.

Where should our oil be then guys? Got mine back from service at the dealer last week and it’s showing an inch above the full mark. Intend to syringe excess oil out down to the top marker, although I suspect the oil would eventually just be burped into the overflow bottle.

Leave it there and ride your bike normally. It will find its level and should stop discharging at this point. Check your bottle often , make sure the tube and drain nipple are not clogged and air box is truly draining.

Stephen_Spencer said:

Where should our oil be then guys? Got mine back from service at the dealer last week and it’s showing an inch above the full mark. Intend to syringe excess oil out down to the top marker, although I suspect the oil would eventually just be burped into the overflow bottle.

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When your bike is on the paddock stand it will read high. It must be on both wheels upright.

TonyA said:

I would rather have the anti-drain back valve where Norton put it (in the oil pump) .

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Hi Tony, Interested in your reasoning there. Both valve options are located in functionally the same location, between oil pump and oil filter, with I am guessing less than a cup of oil to fill the gallery between the factory and Thiel locations. It seemed to me that the less restrictive option could only be good. Of course i would say that since i have already fitted Ollies one

New V old dip stick lengths. The old min mark is about level with the new max mark. The factory way was around 1/3rd up from min, on the longer dip stick....which equates to approx 1.5ltr at oil change.
Personally, I see the longer dip stick, the shoddy pressed in check valve and the Yamaha R6 aos clone, to be a half arse band aid repair.

TonyA said:

When your bike is on the paddock stand it will read high. It must be on both wheels upright.

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Thanks Tony, I’ll keep a good eye on it. It sits on wheeled stands at both ends but the rear is slightly higher than it would be on its wheel. Oddly I check before I ride and when I get off after the ride - always higher on the stick after a ride of course. I get very little oil in the catch bottle.

Fast Eddie said:

Assuming you do not run the oil low enough to starve the engine, then the biggest issue with running reduce oil capacity is heat.

One of the primary purposes of an external oil reservoir is to allow the oil to cool before being returned to the engine.

Air cooled engines give their oil a hard time with heat anyway, therefore reducing the reservoir capacity will make this worse.

So if you choose to run a lower oil level, you’d be well advised to increase your oil change frequency.

Click to expand...

Actually, the oil cooler is the primary source for "oil cooling" on the 961. Increased oil capacity helps but to a very, very minor degree because a cup more or half a quart more isn't going to cool anything down. Once the oil is hot, then it's all "hot" until something cools it down. I won't go too far down with the explanation, but more oil doesn't actually mean better cooling in most cases if nothing cools it down. The idea behind oil level and cooling is to make sure it stays within the proper range of viscosity.

If you didn't have the oil cooler, the oil would remain at relatively the same temperature as the oil entering tank would be as hot as all the oil in circulation.

You have to look at the oil in the frame design. On a 961 the oil tank is heated as well by the rising engine heat, so that's also adding heat not cooling it. The oil tank is surrounded on three sides by the gas tank, and there is very little airflow. Bourget did this with his bikes, and they ran hot as well, even with a cooler

Look at the Harleys. Oil filters in the airflow and those that have them, oil coolers in the airflow. Even the oil bag(tank) is out in the open to help with cooling but it has air circulation on almost all sides.

Keeping the oil pump circulating properly, proper flow, etc, all work to keep the oil temp where it needs to be.

On the other hand, low oil means the same oil must now make more passes through the system without a proper cool down that causes the oil to break down faster. This is even more critical on bikes that have oil sumps versus tanks. The oil sits in the bottom of an already hot engine, then gets cooked via the clutch friction, etc, which is why many prefer a separate engine, primary, gear.

This is why I've stressed looking at your oil tank output and the way the oil pump intake hose is routed, the inline filter, etc from previous posts

ntst8 said:

Hi Tony, Interested in your reasoning there. Both valve options are located in functionally the same location, between oil pump and oil filter, with I am guessing less than a cup of oil to fill the gallery between the factory and Thiel locations. It seemed to me that the less restrictive option could only be good. Of course i would say that since i have already fitted Ollies one

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Hello , I meant that I really like Thiels anti-drainback valve . If I had my choice I would rather an improved/replaceable valve was put in the oil pump. This , I thought would make it easier to replace. I love the valve and think you did a good thing installing it.

City Garage said:

Actually, the oil cooler is the primary source for "oil cooling" on the 961. Increased oil capacity helps but to a very, very minor degree because a cup more or half a quart more isn't going to cool anything down. Once the oil is hot, then it's all "hot" until something cools it down. I won't go too far down with the explanation, but more oil doesn't actually mean better cooling in most cases if nothing cools it down. The idea behind oil level and cooling is to make sure it stays within the proper range of viscosity.

If you didn't have the oil cooler, the oil would remain at relatively the same temperature as the oil entering tank would be as hot as all the oil in circulation.

You have to look at the oil in the frame design. On a 961 the oil tank is heated as well by the rising engine heat, so that's also adding heat not cooling it. The oil tank is surrounded on three sides by the gas tank, and there is very little airflow. Bourget did this with his bikes, and they ran hot as well, even with a cooler

Look at the Harleys. Oil filters in the airflow and those that have them, oil coolers in the airflow. Even the oil bag(tank) is out in the open to help with cooling but it has air circulation on almost all sides.

Keeping the oil pump circulating properly, proper flow, etc, all work to keep the oil temp where it needs to be.

On the other hand, low oil means the same oil must now make more passes through the system without a proper cool down that causes the oil to break down faster. This is even more critical on bikes that have oil sumps versus tanks. The oil sits in the bottom of an already hot engine, then gets cooked via the clutch friction, etc, which is why many prefer a separate engine, primary, gear.

This is why I've stressed looking at your oil tank output and the way the oil pump intake hose is routed, the inline filter, etc from previous posts

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It wasn’t until I read your 6th paragraph that I realised we are actually agreeing !

If course I also agree that the oil cooler cools the oil, but so does the time in the reservoir. They both work to cool the oil. That’s what every oil tank on every dry sump engine has done ever since they were invented. That‘s why race bikes carried more oil than road bikes, to allow more time in the tank to cool down… adding weight to a race bike is only done for good reason!

You’re right about heat from the engine radiating to the tank, that’s not an ideal design at all. But I’d imagine it’s a small factor, when we talk about the oil tank ‘cooling’ the oil. The oil doesn’t need cooling completely, it means taking away the extreme / damaging heat that is reached inside the engine, and allowing the oil to cool back down to its ‘safe’ operating temperature, and to cool enough so there is a big enough difference it temperature (between the oil and the engine internals) for the oil to absorb / extract heat from the engine as it circulates. The large surface are of the steel tank / frame will act as a reasonable heat sink for this purpose (one reason why alloy oil tanks are preferred over fibre glass on race bikes).

That‘s another reason why your comments about ensuring full oil flow are so valid IMHO, not only to protect oil pressure, but to allow full oil flow, the more oil flows through the engine, the more heat it extracts.

When you really think about it, there is actually no such thing as an air cooled engine, the oil does A LOT of the cooling, all ‘air cooled’ engines are air / oil cooled in reality.

Personally, I‘m also surprised that the 961 uses semi synthetic. Good quality synthetic oils have a much greater ability to resist breaking down under heat. If y’all on this forum haven’t done so already, you should read the excellent oil testing done by Comnoz, he was primarily interested in classic Commandos, but, of course, there are many similarities.

Why isn’t the 961 oil tank mounted lower and in an area where it’s unshrouded by anything?

I’m sure the air filters could have been placed elsewhere also, to allow the oil tank to be where it belongs.

Voodooo said:

Why isn’t the 961 oil tank mounted lower and in an area where it’s unshrouded by anything?

I’m sure the air filters could have been placed elsewhere also, to allow the oil tank to be where it belongs.

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I think this is an issue that was caused by the original designer, Dreer. He thought he would be saving weight by using the frame as an oil tank. This was a common idea with frame designers in the 60's. And the area where the tank normally went could house a small airbox to give the bike a svelte - wasp waist appearance. Everyone loves the visual effect of the open space below the airbox, so it was kept by SG.
There is not much in the 961's design that is truly innovative, it was mostly about classic appearance.