Forum

[Presto]

It seems that the problem with using engine oils in the Enfield primary drive is not so much to do with the oil or its grade; the problems seem generally to come from additives in the oil which may not suit Enfield clutches. That some engine oils seem OK in the Enfield primary drive isn’t surprising – it may be that their make-up and/or make is less of a problem than other types of oil. Silkolene do not state the viscosity of their ATF. But ATF is often cited as 6cst at 100 degrees c = approx 20 sae. EP90 is cited as approx 17cst at 100 degrees c. That’s a much higher viscosity than ATF and heavier than would be ideal. ATF is a trouble-free recommendation for the primary drive.

[Micah]

you want it to say "non friction modified" on the label.

[Leon Novello]

As it says in the Snowvalley link. Type F for Fords, it is more grippy.

[Ian Martin]

All very interesting stuff! Mine is a 1992 500 Bullet and I use ATF in both the primary drive case and the front fork legs. I have no problems with its performance in either area. The primary drive ATF drains out the same colour (red) it went in after a years use, it doesn't leak and the clutch neither drags or slips. The primary chain seems well lubricated and rarely needs adjustment. The forks were rebuilt this year using Mr H progressive springs and new seals which has transformed their action, I wanted to try the ATF in them due to its viscosity and this proved to be very successful . IMHO this stuff is a "wonder" lubricant and I wish I had known about it years ago!
Ian

[PeteF]

Ian, I use ATF in the primary and forks as well. Like you, I have no problems at all.

[jefrs]

For info - The EFi (mine) is unit construction (UCE) and hence does not have separate oils, so here we have to use "JASO MA" (spec is 15W-50 API SL grade JASO MA, Ester, Semi-synthetic oil).

The "JASO MA" bit means suitable for wet plate clutch. Over the years they've put additives into off-the-peg motor oils which make the standard oils unsuitable for these clutches.