Britbike forum Forums British motorcycles in general British motorcycles in general 1160 zinc 1200 phosphorous

I like talking about oil and I know everyone else does, too!

I see that some motorcycle 20w50 oils even api SM contain more than 1000 zinc and phosphorous so are alright to use with a Triumph 650. I have always avoided them before but I think I will give one a try. A lot of the synthetic ones aren't proper synthetic like Mobil 1, however, but are probably better than mineral. I don't thrash my bike so probably won't make much difference. Is zddp only a last resort part of the oil that comes in to play when you are thrashing the bike to f*ck? I have mineral oil in at the moment.

Dave

If it's less than 10 bob a pint, i'll use it in these old crates.
Sg and previous is fine, it's all they had back then and all they need.

I'm currently using Motul Classic 20W50 which has an API grade of SF and claims to have a zinc level of over 1800ppm plus a Molydenum additive to reduce wear, see technical data sheet here

Seems to be a good high performance mineral oil, readily available on eBay, Amazon & Opie oils.

I run Mobil 1 V twin 20W50 in the Trident and Valvoline synthetic MC 20W50 in the Bonneville. Both are available in almost any auto parts store in this country.
The Valvoline is a bit cheaper at Walmart if you don't mind walking half a mile to the back corner of the store.
Or, I could just camp out and wait for Amazon to deliver my boutique oil when I'm a quart low and 100 miles from home.

"Gosh, it's not a 1/4-20, must be metric."

How many times have I heard THAT one.

The car shows around here often have a motorcycle section, classes are "American" and "Metric."
They tend to dump the British bikes into the "metric" class (though British bikes AREN'T!)

Probably as many times as I've found an M6 bolt shoved into an outer rocker box hole.

Read where Cenpeco racing oil has zddp in the 2600 area.

A high level of ZDDP is apparently corrrosive. although who defines high?

Perhaps more importantly, who defines "adequate" ? Who thinks the manufacturers ran test engines for long periods of time to test oil additives? Has anyone of the oil companies done long term tests on running engines? Have any of you here done long term testing on actual running street engines? How much ZDDP was in oils back in the 1970's?

Well yes they do, but usually on testing machines not on actual engines unless the engine makers supply the engines .
You have to use test rigs because the testing parrameters have to be identical in order to evaluate the changes that were made to the chemistry .
However engine makers run engines for thousands of hours then strip & measure parts for wear
But for oboloete engines like our BSA's this is not going to happen
The term "adequate" is meaningless
What is adequate for my side valve old banger would be pushing it when used in a bucket cam engine or even an engine with hydraulic lifters let alone a high performance engine with high lift valves and double spring rate valve springs .
So what generally happes is some one gets data from an aero engine company who actually do have to do long term engine testing then it gets blindly extrapolated to cover all engines.
Remember the total BS about valve seat recession when unleaded was intorduced .
That goes back to testing of aero engines under lean burn conditions at a simulated 10,000 feet running at full power .
Not some thing the average BSA rider is likely to encounter

Yep,
The internet spreads mistruths, extrapolations to the level of meaningless and straight lies faster than a US election rally .
Since the beginning of time generating fear in the minds of others has been the fastest & most perminent way to assert power & authority over them

The truth is only Moto Guzzi has bike engines with flat tappets as used in the automotve OHV terms.....Cylinder shaped lifter with a convex contact surface that rotates running on a cam designed to help the rotation....