Douglas - For Sale Items

Douglas 1913 Model P motorcycle

Douglas - Wanted Items

Douglas 1915 3 Spd-Gearbox and Clutch

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


Dave

2025-01-07, 19:16:39
Forgotten your password?
Click the 'Log in' button in the main menu, then use the 'Forgot your password?' function to create a new one.

The new password will be sent to your email address. If your email address has changed since your last login, that method won't work as the email will go to the old address in your profile.
In this case, use the 'Contact' option in the main menu to send us a message and we can issue a new password.

Dave

2024-06-11, 21:02:05
Have you tried the new Drafts feature yet? I just lost a long message today and learned my lesson. It is a good idea to save a draft of any long post you are writing. You can then just keep writing and keep saving a draft, knowing you have a backup if there is a glitch. The draft is automatically deleted when you post the message.

Dave

2024-06-08, 19:30:04
For Sale
xman has two very nice 1950's machines available - a green 1950 mk4 and black 1951 mk5 - both in good condition and running well.

Dave

2024-06-07, 03:13:36

Dave

2024-06-03, 09:23:05
For Sale
Duncan has just listed his green and cream 1957 Dragonfly for sale with spares and documents.

Dave

2024-06-02, 09:34:05
Parts avalable
alistair still has parts available - barrels, carburettor, castings - see all listings.


Dave

2024-06-01, 19:33:27

Dave

2024-05-28, 01:09:46
Welcome to the new site!
Recommended viewing for a fast start...
 - Quick Tour of the Front Page
 - Quick Tour of the new Attachments
Learn all about attaching photos in the User Guide. Any problems with anything please Contact us     Faulty links fixed - 01June2024

Valve timing EW 1926

Started by PhilEW, 09 Apr 2021 at 12:52

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

PhilEW

Hello,

Can someone confirm that this arrangement is good, the key faces the rear cylinder (dot on the gear).


Doug

According to the handbook, with the key to the rear cylinder the cam lobes should be on the tappets for the front cylinder.
See this post:

https://www.douglasmotorcycles.net/index.php?topic=6035.msg22233#msg22233

-Doug

Paul H

Hi PhilEW,
I have just retimed my cams after regrinding them. The valves are timed at top dead centre. On my EW600 the pistons are at top dead centre when the key is facing forward but some models may have the key reward at TDC. This is the place to set the timing when the valves are rocking from exhaust to inlet on the front cylinder.
Paul.

cardan

Quote from: PhilEW on 09 Apr 2021 at 12:52
Can someone confirm that this arrangement is good, the key faces the rear cylinder (dot on the gear).

Hi Phil,

Keys and timing marks are good things to talk about on a new - or nearly new - engine, but one something pushing 100 years old it's best to ignore them entirely. If they line up where they should, excellent, if not parts have possibly been changed or altered.

Your photo at the top looks good is the rear cylinder is at top dead centre, but no promises about the mag!

My suggestion would be to put a pointer at the top of the flywheel, and put a mark with a texta pen at TDC. Then, for each cylinder, check where each valve opens and closes: the chart Doug links to says inlet opens 15 degrees before TDC, exhaust closes 15 degrees after. In your pic, the exhaust is just closing and the inlet just opening - in an old engine this is usually roughly symmetric about TDC. (Amazingly, in some old engines the inlet didn't open until maybe 10 or 15 degrees after TDC!) If you rotate the engine forwards through one complete turn you should have much the same opening/closing pattern of valves at TDC on the other cylinder.

If the inlet opens/exhaust closes is OK for both cylinders you should be right. You can check where inlet closes and exhaust opens, but there's not too much you can do if they'e wrong due to wear/old age/wrong parts.

Looks like there is some vernier adjustment with the three keyways on the half time pinion? You might be able to get better valve timing, even if your marks no longer align.

Leon

PhilEW

Thank you for your helpfull replies, i will look at this carefully as soon as possible.

Philippe

PhilEW

Finally, the timing of the camshafts was right, but the ignition timing wrong, too much advance. As i did not want to remove the magneto gear, I removed the upper camshaft axle, the gear on crankshaft and could turn the magneto gear. One tooth of difference and it was right.

The bike now starts and runs well.

Thank you for your help.