1978 900SS rebuild - oil?

[machten]

Just thought I'd let you know that the Penrite HPR 50 is an automotive oil, "Not recommended for motorcycles".

That's true. But I'd suggest it is not recommended for "modern motorcycles" that are wanting to pump high pressure oil. Personally, I don't buy in to that "motorcycle oil" classification as it applies to our classic bevels. The lubrication engineers I speak to tell me that the major impact of reduction of ZDDP for classic engines is in breaking in a flat tappet engine...beyond that it is a fairly trivial difference. You pay a premium for "motorcyle engine oil". I have no connection with Penrite, but I use these two:



The HD Oil 50-70 I use for running in as it has a very high (by today's standards) ZDDP and the HPR 50 I use for operating afterwards - still high, but more affordable - $36 for 5 liters.

Last week it was time to take the head off my 250 desmo twin filler to set the valve shimming after it's first 3000km. These red line at 9K+ rpm, and you don't run these at less than 4.5K+ cruising, and you dont change gears much under 5K rpm, so they get a work out at the top and bottom end. I'd run HD Oil 50-70 for the first 500km and HPR 50 for two cycles since then. The top end rockers and cam (which were new when installed as part of the rebuild) were pretty much pristine. That's good enough for me.

I agree with radecal's comment:

Bottom line, change oil regularly and use a good grade with proper ZDDP levels and the bevels will be happy.

That being said, I don't think you need to break the bank to do it (yet!)

Kev

[radecal]

Kev,
You are dead right about the cost factor.
I should have clarified what I said about the Hi-Tech Racing 50 oil Ron Young specified as used in his race engines.
The Tart doesn't have an ordinary 750GT engine hence why I run her on the higher spec oil. My others bevels don't have Hi-Tech in them.
My 82 900SS has always run Castrol CRB 50 grade diesel oil from when I got her (ran on it when rebuilt by previous owner) but Castrol has replaced it with DD50 (new number, higher detergent and lowered the ZDDP specs as well) so time to switch her over as my supply has run out recently and she is due.
Interesting that Gowie recommended that oil for bevels as it kept them clean inside.
I sorted out a Darmah for a bloke a while back (very low mileage basically not run in, sat for many years) and hit her with the 50-70 for the first runs and back to regular 50 grade when it has had a chance to bed in as per your regime.
Besides Penrite is Aussie and so is Hi-Tech!
Regards,

[Steve Foster]

Kev,
I contacted Penrite seeking technical advice. I asked:

Could you tell me why you state that the HPR 50 (40-70) Mineral is "Not recommended for motorcycles"?

The response from a Penrite Technical Officer was:

The official line is that these may be friction modified at some point in the future, if necessary. In this case there would be potential trouble for motorbikes using these oils as they would not function correctly with a bike's wet clutch.
If you have a bike with a dry clutch, or one where the engine oil is separate, then these oils are fine -there's no issue with the engines themselves. A safer option for bikes in place of HPR 40 is Enduro, not friction-modified, 25W-70, with zinc at 1760 ppm (ie "heaps"). The alternative to HPR 50 is HD 50-70 (also 1760 ppm zinc).

So it looks like you're spot on with your Penrite choices.

I like the technical assessment that there's "heaps" of zinc in these oils.
Steve.

[machten]

I contacted Penrite seeking technical advice

Good work, Steve!!! <> (although asking someone who knows the answers almost seems like cheating )

The official line is that these may be friction modified at some point in the future, if necessary. In this case there would be potential trouble for motorbikes using these oils as they would not function correctly with a bike's wet clutch.

That's really good information to know. Thanks for your efforts researching and sharing. I suspect a lot of us check out oils, settle on our preferred brand and product name and then keep buying it without considering that their contents may change over time. I'll certainly keep a look out for that, and in fact, I think I'll buy a few drums of HPR shortly

I looked at Enduro, but after a bad earlier experience with a 15W-50 "motorcycle" oil that was recommended to me resulting in leaks in places I'd never seen before, I was reluctant to run low first viscosity multigrades again. (Anyone want 25 liters of unopened 15W-50?) The leaks and weeps stopped with 40-70. Note however that Vince has said earlier in this thread he's using Enduro and he would be far better placed to comment on Enduro than I.

And my humble apologies to all for contributing to another "oil thread" - but I guess it's a moving target and also the most important servicing regime for our bevels.

Kev

[Vince]

Yes I am using Endro in my Laverda,I was using Sin.Thats the Penrite full Sinthetic but its realy realy thick with long warm up times.I am having no leak issues with the Endro,its nice to have good tech info from my Laverda owning ex Penrite sales rep mate.Time for another change.I will probably use it in my Pantah as well.BTW Endro is 25w70

[Craig in France]

<snip> I like the technical assessment that there's "heaps" of zinc in these oils.

Yep, that's the kind of techno-speak I can understand . Seems to be 'bout right, too ...

[abmartin]

I use 40 wt diesel oil.

Bruce

[Craig in France]

Just to keep the pot boiling ... . A couple of reflections from the industry on ZDDP:

1. Caltex
"The old zinc/phosphate based anti-wear additives are not the only way to achieve anti-wear chemistry. (…) It isn't appropriate to compare the anti-wear properties of an oil by considering the zinc content alone.

Some of the concerns about modern engine oil chemistry are raised by third party oil additive companies, who need to tell such stories to market their unnecessary products. Generally, modern oils benefit the older engine designs, and there is no need to seek out low quality oils, or to add extra unnecessary additives."

James Cull
Caltex Customer Services
Chevron New Zealand
---------------------------------------------------------------------------------------------
2. Silkolene
"As for this ZDDP business, it's not just a simple 'High Zinc Good, Low Zinc Bad'. Suffice to say that oils with adequate, but not unnecessarily high, ZDDP levels are fine, especially if the load-carrying is boosted with synthetic ester and the oil film thicknesses are maintained by shear-stable polymers.

Zinc level in the (Silkolene) Pro and Comp grades is 1100ppm."

http://www.silkolene.com/index.php?calling=oilclinic
--------------------------------------------------------------------------------------------

P.s FWIW: Silkolene Comp 15-50 is what I use these days ...

Ciao

Craig

[radecal]

G'day Craig,
Just to keep the pot boiling ... just a bit more!!!
Main issue is with the industry blokes' statements is that modern metallurgy has overcome a lot of wear issues and modern oils plus modern metallurgy equals better fuel economy, longer oil changes etc. (a lot forced by government laws as well and I am generalising here as the info takes a lot to absorb) but the older engine metallurgy can have problems (mainly top end). As I said previously, check the classic car sites and talk to rebuilders of older machinery as the newer, lower ZDDP oils may not make the grade. They have added other substances for lubrication and most have gone to Ca based detergents from memory.
I am not sure if our older metals/systems like these materials either.
Most of the long time bevels I am aware of have done a number of good things. Main one as Ken and I have said is to change oil (and filter) very regularly plus the way they are ridden has a big bearing (pun intended) on it. Lug them in top gear at low revs and wait for the hand grenade!
Ride them like they were intended.
Regards,

[Craig in France]

Tsk! I wish you'd be a bit more controversial, Bob - this is an oil thread, after all .

Do you think we should warn Bruce about the risk he's running, what with all that detergent in his diesel oil?

[radecal]

sk! I wish you'd be a bit more controversial, Bob - this is an oil thread, after all .

Do you think we should warn Bruce about the risk he's running, what with all that detergent in his diesel oil?

Craig,
I think we need to see the FINAL outcome of all that detergent on the young lady first before we warn him.
Have to weigh up all the positives and negatives first before giving a final business decision.
Regards,

[abmartin]

You guys are lucky - at least you have choices. Here in the wilds of rural Canada diesel oil is about the only single grade motor oil I can get. Maybe I should put a little in my bath water.

Bruce