My Douglas

[Web2002]

Bought about two years ago and now nearly completed light restoration.

Need advice on the carb if any one has any useful info. Its an AMAC with separate float chamber and badly leaking from both chamber inlet and inlet into carb body. Hyper Blue stops it but would prefer a better method.

Also I want to incorporate a fuel filter whilst still retaining the copper fuel pipe look, any ideas?

I would be interested in purchasing a complete AMAC/BINKS carb and float chamber for this machine if anyone has one?

Also interested in final drive belt ideas, would prefer a black one with tensioner, again, any steerson this? The current orange one works but obviously doesn’t really look the part!

[EW-Ron]

Nice looking bike, its coming along well.
I've never understood this urge to hang them from the sky though ...

You can buy spray-on fabric dye/paint.
A coat of black would instantly transform that belt,
not sure if it would make it slippery though.
You have nothing to lose, steel wool would probably roughen it up
or even remove it again if this was a problem ?

[eddie]

As you have the 1915 onward frame, you could use an ordinary continuous 'V' belt. You just need to unbolt the RH side of the stand and the RH frame stay to lace the belt around the back wheel.

  Regards,
                 Eddie.

[cardan]

Interesting carburettor and controls. I wonder could you post photos of the carb and magneto controls and the carburettor itself.

Recently (https://www.douglasmotorcycles.net/index.php?topic=8174.0 ) I mentioned there were five or so possibilities for Douglas carb and mag controls in the period 1922-1925. Your controls look to be the AMAC type current from 1920 - 1922, usually seen on the larger Douglases but I'm sure were used on some 2 3/4 bikes. What year does the engine and frame number suggest?

The attached image shows the 1920-22 AMAC lever on a 1922 S1 (500 ohv).

There's nothing on an AMAC that can't be fettled without Hyper Blue, and unless the inside of your tank is actually rusty, a fuel filter is probably not needed. Just drain the fuel line and the fuel bowl on the first few rides until the rubbish is washed through.

Cheers

Leon

[Web2002]

Hi Leon

I had the tank cleaned and repainted and it’s nice and clean inside. Following dismantling of the carb and float chamber I realised how many important openings could be blocked by a bit of debris, thus wanting to fit a discrete fuel filter. I have a plan now.

A couple of pics added of controls and carb slides.

I’m told the frame is circa 1921 and engine 1924.





Image orientation fixed - Dave, 01 July 2020

[Web2002]

Slides




Image orientation fixed - Dave, 01 July 2020

[Web2002]

Nice looking bike, its coming along well.
I've never understood this urge to hang them from the sky though ...

Not sure what you mean “hang from sky”?

You can buy spray-on fabric dye/paint.
A coat of black would instantly transform that belt,
not sure if it would make it slippery though.
You have nothing to lose, steel wool would probably roughen it up
or even remove it again if this was a problem ?

Don’t think thats going to work and if it did it wouldn’t stay on for long.



[fix quotes. -Doug, Site Moderator 30Jun20]

[cardan]

Lovely AMAC carb and levers - perfect for 1920-22, even though I'm pretty sure Douglas also used the "old fashioned" T30 HD AMAC levers during the period.

Could I trouble you for a photo of the mag lever? I've just changed the carb and levers on my 1920 Blue Bird (Australian made, JAP V twin) to the 1920 AMAC setup after 35 years using it with a mish-mash of carb and levers. After my fiddling with these AMAC levers I'm pretty sure that the body of the left single lever is the same part as the right double lever, but with a blanking cover underneath. I'm missing this bit, but I can improvise. I suspect the levers were overly complex and expensive to make, thus the new AMAC "K model" levers from 1923.

Re the carb. It looks like you have exactly the correct item, which puts you well ahead of the game. In fact there is only one very small hole in the carb - the main jet. You will see that the jet is in a weird place: submerged under the array of "spraying holes" that form a line across the body of the mixing chamber. I suspect fuel level is not too critical in this arrangement, but it should be somewhere just below the spraying holes, with the main jet (a metering device, not a spraying device in this case) submerged.

When the fuel is turned on, the float chamber should fill and not a drop should be seen anywhere around the carb.

Re the fuel filter. Feel free to fit one, but it is not needed.

Cheers

Leon

[EW-Ron]

Not sure what you mean “hang from sky”?

Nothing much really -  its just one pic as posted is upside down....

[Web2002]

As you have the 1915 onward frame, you could use an ordinary continuous 'V' belt. You just need to unbolt the RH side of the stand and the RH frame stay to lace the belt around the back wheel.

Hi Eddie, thank you for that, can you recommend a supplier and size of V belt? It appears to be 21mm across and 19mm deep (no dice available to me for measuring the deep V width).



[fix quotes. -Doug, Site Moderator 30Jun20]

[Web2002]

Not sure what you mean “hang from sky”?

Nothing much really -  its just one pic as posted is upside down....

Hi Ron

All the right way up my end. Having said that they have distorted the last ones I posted, so who knows what happens in the ether-net!!


[fix quotes. Doug, Site Moderator, 30Jun20]

[Web2002]

Lovely AMAC carb and levers - perfect for 1920-22, even though I'm pretty sure Douglas also used the "old fashioned" T30 HD AMAC levers during the period.

Could I trouble you for a photo of the mag lever? I've just changed the carb and levers on my 1920 Blue Bird (Australian made, JAP V twin) to the 1920 AMAC setup after 35 years using it with a mish-mash of carb and levers. After my fiddling with these AMAC levers I'm pretty sure that the body of the left single lever is the same part as the right double lever, but with a blanking cover underneath. I'm missing this bit, but I can improvise. I suspect the levers were overly complex and expensive to make, thus the new AMAC "K model" levers from 1923.

Re the carb. It looks like you have exactly the correct item, which puts you well ahead of the game. In fact there is only one very small hole in the carb - the main jet. You will see that the jet is in a weird place: submerged under the array of "spraying holes" that form a line across the body of the mixing chamber. I suspect fuel level is not too critical in this arrangement, but it should be somewhere just below the spraying holes, with the main jet (a metering device, not a spraying device in this case) submerged.

When the fuel is turned on, the float chamber should fill and not a drop should be seen anywhere around the carb.

Re the fuel filter. Feel free to fit one, but it is not needed.

Hi Leon

I’ll post some below. ref the carb, I’m persevering with it. As to levels, If the float bowl is mounted forward of the carb body as recommended by AMAC it leaks because the float level is higher than the 4 little atomiser holes you describe, so I’m keeping it south of the carb body, not sure how authentic this is and will no doubt find out how effective when I meet my first hill!!

David


fix quotes. Doug, Site Moderator, 30Jun20

[Web2002]

Control levers













Image orientation fixed - Dave, 01 July 2020

[cardan]

Thanks so much for the photos of the controls, even if you have proved that I'm using half a double lever instead of the real deal for my magneto lever. I will keep looking... jealous that you have the correct pair.

Re your carb: With the bike on its wheels on flat ground the fuel level should be the same regardless of where the bowl is located. In front is correct, so that the fuel level rises when you're going up a hill to give a richer mixture. If it floods, either move the clip a couple of mm down the needle, or if there is only one notch put a spacer (small fiber washers work well) between the top of the float and the clip.

Have fun.

Leon

[Doug]

Nothing much really -  its just one pic as posted is upside down....

All the right way up my end. Having said that they have distorted the last ones I posted, so who knows what happens in the ether-net!!

Note: The inverted or distorted attachment are all manifestations of the issue with the EXIF data (which stores among other things the camera orientation) in newer smart phone pictures not being fully compatible with the Forum software. It is a little more involved than that, presumably the type of browser plays a part as well. Some folk see the image correct, and other see it distorted or rotated.

-Doug, Site Moderator

[EW-Ron]

Interesting. Who'd a thunk the protocol for images could go wrong at such a basic level !!

I use several other forums that have the same source, with no such problems (?).
And this one seems to be the later version ...

[graeme]

As for belt, you need a C section V belt. I have used Opti-belt on veterans, bought at a bearings stockist. The belts come in 1 inch increments, so you need to work out what size you need from the current belt you are using. I have found I have needed to exchange the belt at least once always to get the right size!

[cycarmark]

The AMAC carb float body on my 1920 Clyno looks similar to yours.  The float needle has no grooves, but is held in place by a clip and a spring over the needle.  The float level can be adjusted by moving the clip and spring.