Author Topic: I bought the Douglas!  (Read 3562 times)

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Offline HughesNigel924

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I bought the Douglas!
« on: 30 Aug 2016 at 09:26 »
After many years thinking , re-searching and waiting I have at last gone for it!

I m now a proud owner of a Douglas 350 cc (1950).(What a great decision!)

My first ever bike and have a very steep learning curve ahead ( Very exciting)

The only disappointment was when I went to view and pick up my New purchase it would not start.
However the seller got it started with a bump. It sounded great although would cut out at tick over.

My intension is to try new plugs and leads first to see if this makes any difference.

The question I would like to ask is does anyone live in Hinckley, Leicestershire that may be able to lay a hand in getting my immaculate Douglas started before the weather closes in.

Kind regards

Nigel Hughes.



Offline Vermont-Ian

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Re: I bought the Douglas!
« Reply #1 on: 05 Sep 2016 at 11:11 »
Hi Nigel,
Any engine from 1950 that won't start either has no fuel in the cylinders, or has no spark.
From what you wrote, I suspect weak spark, easily verified by taking out a plug and turning over the engine.
If no spark, it's either plugs or magneto - you've tried new plugs.
If magneto, first clean the points and check the gap.  If still no spark this could be a common problem in old Lucas magnetos - you'll probably have to get the windings and capacitor replaced.  There are people in UK who do that.
I'm no where near Hinckley, Leicestershire, so can't be of direct help!

Ian
Ian Stokes
Richmond, Vermont, USA
1948 Mk III
1936 Citroen 'Traction' 7C

Offline eddie

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Re: I bought the Douglas!
« Reply #2 on: 05 Sep 2016 at 15:15 »
Nigel,
          As Ian says, it could be lack of fuel or weak sparks. Since the introduction of unleaded fuel, machines that have been idle for some time often suffer from the petrol separating out and leaving a sticky lacquer in the carbs which makes starting difficult. It pays to run the carbs out of fuel after each run if the bike isn't going to be used again for a few weeks.
 If the sparks are suspect, after cleaning and setting the points, check out the spark plug leads. Magnetos work better with copper wire HT leads and unsuppressed plug caps. With the modern fuel, the favourite plug for a postwar Douglas seems to be the NGK B6HS.

  Regards,
                Eddie.

Offline shuswapkev

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Re: I bought the Douglas!
« Reply #3 on: 06 Sep 2016 at 10:44 »

I have brought an old maggy to life by planting a few rare earth magnets on the side...my horseshoe magnet had lost all its force..after only 80? years
  the magneto obviously needs a good going over ..but at least  I got it running

I also parted together a K2F for a BSA..just a bunch of loose bits...Didn't seem to work real well.....  picked up a brightspark condenser and nipped the lucas condenser out of line.....as the website instructions...wallah...1000 miles later...still going very strong

other than all the expensive stuff...you do have new solid copper high plug wires, new non resistor plugs...gapped to magneto specs.......checked all the maggy brushes...(3)... and wiped the contacts clean...have clean contact for the points to magneto frame and good point contacts,   checked for compression...  a good magneto should spark across about 5/16 ...if you take an old plug and bend or break off the earth electrode...that should give you a 1/4 inch gap...it,ll run if it will jump that.. then just squirt some gas thru the plug hole...
also have to remember when turning over a magneto...it always throws a spark...if there isn't a earth connection thru the high tension...it will go to ground back thru the old weakly insulated but very expensive coils...burning a hole in them..always keep a plug in that is earthed

happy trails
   and we hope to see some smoke rising from your shed soon...

Offline eddie

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Re: I bought the Douglas!
« Reply #4 on: 06 Sep 2016 at 11:17 »
DO NOT EVER try to get a mag to produce a spark over 4mm long! That is the quickest way to ruin the windings - the spark will find the easiest route to earth - and that is across the windings. That was the reason BTH fitted the earth gap screws at 90 degrees to the HT pickups - so that the spark had a route to earth before causing irreparable damage to the armature.

  Regards,
                Eddie.

Offline shuswapkev

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Re: I bought the Douglas!
« Reply #5 on: 06 Sep 2016 at 11:58 »
ahhhh  we have a dispute...

  I,ll go with these guys....  I have used their info and had a positive outcome everytime

http://www.brightsparkmagnetos.com/DIY/12.htm

about halfway down the page

  may be a specific point...I have always had and worked over later model lucas maggys...1946 and on...they have a safety gap...

what model magneto does a 1950 douglas use??

   I don't know if my douglas magneto has the safety gap...

Offline eddie

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Re: I bought the Douglas!
« Reply #6 on: 06 Sep 2016 at 15:22 »
A 6mm spark is fine providing you are sure that the mag has been kept in dry conditions - or been in recent use, but if it's on a bike that hasn't run for several years, the chances are that the armature will have absorbed some moisture. The spark will then find an easier path across the coils, and you have reached the point of no return - the only solution is an armature rewind.

  Regards,
                Eddie