Friction eliminators

Informed opinion suggests that it is a waste of money. Modern lubricants do all that is required, and probably a good deal more. I am a bit old fashioned and use Morris's 20-50 inwinter, SAE 40 in summer (SAE 40 all year round for the singles with roller big ends). If you want to give the best possible protection, consider fully synthetic oil rather than additives. Gordon.

William, did you suggest 10/40?

Been using Slick 50 along with straight 50 all year round in my Commando for the last 20 years and i use very little oil between changes.

Slick 50 etc are not friction eliminators. Like the poor, friction is always with us. Friction losses in the engine are mainly due to viscometric factors.

Slick 50 is based on a suspension of PTFE which you add to your normal oil. It is less clear what additive is used in ZX1.

Both claim to work by coating metal surfaces and reducing friction and wear which occurs when the oil film is unable to separate surfaces which slide one against another.

These conditions can occur at start up and in the contacts between the cam and follower.

In a conventional oil,wear is controlled by the ZDDP class of additives and friction reduced as a consequence. In Fuel economy oils, further reduction in friction is achieved by the use of either organic friction modifiers such as glycerol mono oleate or to even lower levels by the use of Molybdenum compounds which form Molybdenum di sulfide at the surface.

Relative to a non friction modified oil, the Molybdenun oils will show a 60% reduction in boundary friction which translates into a typical 2% increase in power or in fuel economy.

I have evaluated a number of these after market additives for friction and wear properties, but found no holy grail.

As a final point, the Fedral Trade Commission judged that the claims made for Slick 50 to offer exceptional protection were unsubstantiated.

One of thelosses in the Norton engine is caused by the bottom of the skirt of the pistons shoving oil out of the bores on every downstroke. Phil Irving advocated turning the bottom of the skirt of pistons to a knife edge to reduce this pumping loss. Cheaper than adding friction modifiers! Gordon.

Charles,

Hadn't thought about frictional losses due to oil viscosity before. (Although it should be obvious when kickstarting on a cold morning.) Currently use a synthetic 20/50, but I think it has been suggested before that a 10/40 should be ok?

Simon.

Been using Tesco 10/40 synthetic for years in MKIII - no problems, runs cooler, rides better from cold and very very little debris on the magnetic drain plug.

For a while it also had a better classification than Mobil 1 as Mobil 1 was slow to catch up with the new standards.

It does airate as much as non synthetic oil either, so the tank looks like it contains oil and and not liquid foam when checked after a good run.

Cheers Ashley,

I think I'll give 10/40 a go when I've used my existing stock of 20/50. Anything to improve efficiency is worth a look. I assume the cooler running is due to the greater flow rate of the oil, it will be interesting to compare fuel consumption before and after,

Simon.

The Mobile Company did at one time produce a range of Synthetic oils. They may still do. I have used some of their 10/40 butdon't ever remember a 20/50 in their range. I believe there was even a 10/60 available for some engines. The advantages of these syntheticsare many. Much easier starting andquicker distribution of oil around the engine. especially the cylinder head. Less burning or ashing and less moisture absorbtion. The downside when used in most Nortons is the clatter caused by the moving lumps swimming in a thinner goo.

I think Slick 50 is a great additive. I always add it to my oil tank on track days andwhen ridingto far distant rallies. I have never had an engine seizure......even when the oil tank has looked empty.

Ialso once tried another potion called Active 8. It obviously did not do what it claimed on the side of the packet as I subsequently had camshaft followers and guides fail in two different motorsI used it in.

Aside from the effectiveness or otherwise of Slick 50, Mobil offer a 15W50 oil which is available from Halfords + other sources. The commaoil.com website allows you to locate suppliers near to your postal code. OPie oils supply Mobil Racing 4T 15W50 Full synthetic.