Topic: High Zinc zddp Mobil 1 or other oil for rebuilt CB750K1

[rinkeldekinkel]

Hi Guys,

I am rebuilding my engine, and as i am using new japanese gaskets, and every parts is measured and exchanged
i want to be sure that i use the correct oil..

To make things a bit harder, i cant get hold of all these exotic usa made oils, you mention, so if someone could reply my regarding a MOTUL or MOBIL 1 RACING 4T or similar quality AND MORE IMPORTANT available in Europe.

I have had a few bikes in the past, and when i researched the big oil threads, and specialist forums and pages again, i came accross the ZDDP zinc
issue, our bikes have more steel to steel contact than newer engines, and also my HM300's are not yet catalyst equipped
so i want to know that i will buy the best possible oil

In the past i had some issues with the smaller honda monkey engines, that had to put out 5 to 6  times the horsepower they where intended to...
22RWHP instead of 3.1
they had some cam and rockerwear issues because of high lift and duration, as well also the gearbox shiftforks where eaten within the 4000km range
each and every time!!

I used to think that if i only bought a good brand (motul or elf) oil with the highest possible API rating i was fine,....

Guess not, because now after 8 years of these wear issues, i start to THINK, that it COULD have been less problematic had I chosen a ZDDP richer oil.

Please correct me if i am inccorrect,

But i think that i can perfectly use a MOBIL 1 4T 15W40 RACING OR even the Mobil1 VTWIN 20W50 because i have rebuild the engine, and fitted brand new KPE Japanese brand gaskets.
i think that oil sweating would not nessecarely need to be an issue...
But it will protect my steel to steel surfaces like shifterforks, and Camshaft and rockers better
I remember that all car gearbox oils have (zddp) Extreme pressure additives and we share the gearbox with the crankcase.......

Please let me know your feedback if you can!!

According to my research the MOBIL1 Racing 4T oils are motorcycle specific with

• More phosphorus/zinc for enhanced wear protection at high
  engine speeds and high loads.

• NO!! friction modifiers (wet clutch)

• and a 1200 phosphor and 1300 zinc ppm (another document even speaks of 1700PPM ZDDP content according to their racing oil catalogue.

(source)

[goldarrow]

You can use zddp additives.

[edwardmorris]

http://forums.sohc4.net/index.php/topic,119643.msg1700716.html#msg1700716

Good info in that thread. Greg/Ofreen has the highest miles on his 750 on this forum IINM, and like many other I tried Spectro per his recommendation.

[gtmdriver]

Millers oils do a specific oil for the old Austin Mini which also shared its oil with the gearbox. It contains EP additives and they recommend it for motorcycles too.

[rinkeldekinkel]

Hi guys many thanks for your swift replies but unfortunately
I cannot get hold of all the usa brands here in europe
We do not have spectre and or brad penn
My choice would be running in the Mobil and or the Motul brand
Anybody have zddp comments or experience on those?

[PeWe]

I use Red Line motorcycle oil 20W-50. (Synthetic)
This Oil does not need any ZDDP to be added when it has a lot from the beginning.

Oil feels very good and I trust good lubrication of the cam. I changed cam last summer and the oil felt very oily and nice.
Oil was still rather new, about 3000km's . I'm convinced that this oil wuthstand minimum 5000kms, probably up to 8000kms before change.

I used Castrol Actevo 20W-50 before and it felt not that good.

[gtmdriver]

Hi guys many thanks for your swift replies but unfortunately
I cannot get hold of all the usa brands here in europe
We do not have spectre and or brad penn
My choice would be running in the Mobil and or the Motul brand
Anybody have zddp comments or experience on those?

Millers is a UK brand so you should have no problem with that.

[oldhatt45]

I have used BelRay 20W-50 Oil in my K6 since it was brand new.
After a 26+ year nap, I changed the Oil and put in BelRay 20W-50 Mineral and have not had a problem.

Just my experience.  YMMV.

Charlie

[Flyin900]

Watch for just plain ZDDP additives alone as some may have issues with the wet clutches these bikes use. I work PT with an automotive jobber and did contact a ZDDP additive manufacturer about using it in a motorcycle with a wet clutch.
They advised against doing so, as their product did also contain friction modifiers which will destroy the fibre clutch plates.
Don't recall the brand right now but Rislone also makes one that is available in the US and then this company. I will get the name when I am back to work.
Your best bet I think is to stick with oils that have a high zinc content already and are approved for wet clutch use in motorcycles.

[gtmdriver]

ZDDP Plus from Frost Restoration.