1927 EW Carburetion Issues

[Douglas52]

Gents
I have just purchased a 1927 EW, my first Douglas - also my first old bike, and am awaiting its arrival, probably a week away.
The current owner says it is in good nick, but the carburettor needs work as it can be tuned to run well at either high(?) speeds or low speeds, but not both. He thinks its an amal carb. My guess is that the problem is a worn air slide allowing lots of bypass air at low speeds/throttle openings, but I havent really thought it through yet. I would like to have a plan of attack sorted before the bike arrives. Any ideas?

Cheers

Steve

[graeme]

Hi Steve
Congratulations on your purchase - a great choice for your first old bike! Let's hope you can get it sorted so that you can enjoy the machine.
As for the carburettor, first find out just what it is, and whether it is the correct size for the machine. I may be wrong here, but I would have thought that the EW had an AMAC rather than an AMAL as standard? Of course it should work fine if it is the appropriate size AMAL. If you suspect that the slide is worn (highly likely!) get the carby cleaned up in the bore and sleeve the slide. There is a chap in Sydney who does this, and at a very reasonable price. You'll find his details here: www.douglasmotorcycles.net/index.php/topic,646.0.html
There may be peolpe in NZ who do this also.
This would be a starting point, then the usual stuff like checking float height, jet and needle sizes etc etc. I am sure there are other EW owners on this forum who can point you in the right direction here. Also check for air leaks in the inlet tract.
Good luck!
Cheers, Graeme

[Doug]

Steve,

The original carb for the EWs was a B&B two-lever instrument of a semi-automatic type. 123-5 cast on the side of the body. Lacking bits or unable to come to terms with multi-lever type carbs, many have been replaced by later automatic carbs which also allow the use of a twist grip control. A small clip on AMAL like a 74 or a 274 ought to work just fine as a substitute, and may be easier to maintain and tune than the B&B.

-Doug

[Douglas52]

Hi Graeme and Doug

Thanks very much for your reply. I'm looking forward to some fun with this one.

The bike is said to be a '27 model but it looks more like the '26 photos on this website, especially the tank paint, control levers and chain guard.
I have attached a couple of pictures of the bike including the carburettor, which doesnt look that much like an Amal to me.
The offside photo shows a pan shaped object on the timing chest which I assume is a generator.
Would electric lighting be an option in ‘26-27 or would it have been fitted later or is it a later motor?

I’m keen to avoid damaging the bike through unfamiliarity (e.g. forgetting to open the oil valve). Are there any tips or references which might help?

The excellent literature at this website includes quite a bit about the lube pumping and distribution  system which has considerable demand put on it, given it’s a once through system and some of the internal  lube distribution is suspect. Is there a consensus on the best oil to use and how best to maintain the lube system?

The intention is for this bike to be my Sunday morning ride to a pub about 40km away over   gently rolling hills. What sort of speed should I expect to average? Are changes to the lube system recommended when going up steeper hills?

Thanks again for your help.

Cheers

Steve

[Alan Cun]

Hello All, Yes this EW appears to be maybe even a 28 model having the RG/C type sliding round tube base gearbox. Do I also detect detacable heads making it a sports motor????????? Alan      Yes of course it has headstud bolts.

[Douglas52]

A sport motor? RG/C gearbox? Better invest in a full face helmet and some leathers. In that case it might be a bitsa which is OK provided they are good bits. The bike comes with 3 boxes of bits so if anyone can help telling me what bits dont look right, I can have a rummage and see if original replacements are at hand.
Today I had a chat with the owner of the leading local motorbike shop. He told me that his shop was the direct descendant of the original Douglas agents ( W Justice). Apparently the shop sales pitch for the EW was "If it wont go up High street in top , you can have it for free". High street is reasonably steep, so that answers my questions about going up hills, but raises a few others.
For a start I'll probably use 2 stroke lube in the oil system as it should burn clean and give the front cylinder as much help as possible under boundary lube conditions. Not so sure how it will work on the timing gears, cam and follower though. Can anyone shed some light on which engine bits wear the most?

Cheers

Steve

[Alan Cun]

Hello Steve, Yes the sports model EW had detachable heads and I believe alloy pistons other than that I believe the remainder of the bike was much the same as the standard models. As for lubrication we in Aus prefer a 50 grade lubricating oil I suggest Penrite. Or maybe for your colder area a quality oil used in turbo cars. Keep the 2 stroke oil for an additive for adding to premium grade uneaded  fuel which some say does the same as Flash Lube LP Gas additive. As for the front cylinder ignore it from my experience the rear is in draft of the heat of the rest of the motor and from the numerious blowups I have had it was always the rear piston so I prefer more clearance on the rear cylinder. If you can pull up a previous post I did on smoking rear cylinders from 3 X E 29's this may be of interest. Alan