Douglas - For Sale Items

Douglas 1913 Model P motorcycle

Douglas - Wanted Items

Douglas 1915 3 Spd-Gearbox and Clutch

Support & How to Join

Side Panel Notices

Quick Comments

Reminders, links to interesting topics, bump your own topic, quick comments or any short message of interest to members. Try it out!
Please note - 500 character current limit


Today at 01:04:34
Welcome to the new site!

Recommended viewing for a fast start...
 - Quick Tour of the Front Page
 - Quick Tour of the new Attachments

Please see the bottom post in this topic for more info.

1927 douglas ew 600, what oil should i run?

Started by Pops600, 06 Sep 2017 at 23:13

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.


hi guys im at the point where i should be able to run my douglas ew600 but i have no idea what modern oil i should be buying and what modern oil i should be avoiding.

also what petrol would you guys reccomend, standard unleaded or a premium unleaded, and will i need a valve lubricant ie flashlube added to the fuel?


I use Penrite oils (one of the mono-grade classic ones like Shelsey Medium) and Regular 91 pump petrol in all my old side-valve bikes. There might be better, but I have no trouble. If the motor is new an egg-cup of oil in a tank of petrol probably won't hurt.

If you've thoroughly cleaned out the insides of your motor, any motor oil will likely be fine for a lifetime of occasional vintage rallying. Popular wisdom is to avoid modern oils with detergents in old, sludgy engines.

Good luck,



Thanks for the advice, we ordered an oil which penrite suggested as there was nothing on the shelf at supercheap that seemed suitable, the engine was new 30 years ago and dads never ran it, he says the cam timing was out and it wouldn't start but i pulled the plugs and it was full of oil on both plugs so my guess is that was the problem, we have a spare rebuilt engine here aswell which i could swap out.


Another question for you guys, do i need to fill the crankcase with oil  until it is coming over into the oil pump side and then fill that side up until its close to exiting the bottom tube before starting the bike? Im trying to google and reading through my grandfathers books but i cant see anything about how to initially fill it up.


One thing re modern fuels - as Leon says 91 is fine but avoid any with ethanol.

With regard to filling the crankcase and timing side its worth having some in the timing side rather than waiting for it to mist through from the crank side. However as the system is total loss you should just put a few manual pumps of oil in to the crankcase using the manual pump and then set the drip feed to run about one drip every two or three seconds. That will be plenty. You don't want too much as the plugs will foul !


Thanks for the advice,
Penrite sent me out this oil,
Now we have no spark  :roll:


That oil is probably ok. Most people I know use the Shelsey range from Penrite where light is for 30 weight, medium 40 weight and heavy 50 weight monograde oils although it's actually a multi grade !


They tell me this is a true sae30 oil and only stock 4 bottles in new south they have 3  :D