NOW SOLD
1930/ 1931 Vintage Douglas S6 T6 motorcycle engine dismantled ready for rebuild.
These early heavyweight Douglas twin engines are hard to find. They didn’t make many on the models, but they are great bikes for touring.
Typical of Douglas around this period. It was over engineered and high quality.
What’s the difference between an S6 and the T6 model?
The Douglas T6 had a celluloid finish tank and foot boards. The S6 model had a chromium plated tank and foot rests. Both models has a single central front compression fork spring, centre stand and lower links inside girder blades.
If you are looking to see if your frame, or gearbox might match this fairly early Douglas S6 T6 motorcycle engine, then your numbers / letter codes should be:
For 1930/31. Frame letter code is YF**** (=numbers up to around 3200). Gearbox codes are WG****, WG/T****S, WG/O****, GB/***(4-speed option).
In 1932, the engine letter code is still EQ****. Douglas motorcycles decided to give the two 600cc models, names. The 600cc Sports now D32 or Greyhound and 600cc touring is E32 or Ayredale.
I suppose there is no reason that you couldn’t use this early Douglas S6 T6 motorcycle engine with the Ayredale or Greyhound.
About this Douglas S6 T6 motorcycle engine
As you can see, it is dismantled. Most of it appears to be there. The timing gears all look OK.
It has the correct detachable plate style cylinder heads, inlet manifold cast integral with timing cover, ports on the side of the cylinders.
It comes with the flywheel.
The fins on the sump look pretty good, except for one small chip that I have photographed. Of course, the sump will need a good clean out.
It comes with the crank, connecting rods, a pair of pistons with rings attached and gudgeon pins. It even comes with the ali valve covers. The valves are in the heads.
It’s worth pointing out that both barrels have light score marks. I presume this is where a gudgeon pin has made a bid for freedom.
Other Douglas motorcycle parts.
I have a few prewar Douglas spare parts. I happen to have most of another Douglas S6 T6 motorcycle engine. It’s a slightly later sequential number, but still likely to be a 1931 engine. Please see the Douglas parts for sale.
Swaps for this Douglas S6 T6 motorcycle engine
Wanted. Anything Douglas Veteran (pre 1915). I am happy to discuss part-exchange of suitable Douglas parts in exchange for this engine. Also, if you have a Pre-1915 Douglas motorcycle to sell, please contact me.
Sometimes, I put a notice up on TheTimingChest Facebook page letting everyone know that something interesting is about to become available. It may be worth following the page.
BUYER NOTES
Shipping is an additional cost. Please check on postage cost before you buy.

1930/ 1931 Vintage Douglas S6 T6 motorcycle engine dismantled ready for rebuild
I will provide a quote.
International shipping available. Please ask. Combined shipping available.
Viewing: Please come and check it over before you buy. It is at PE28, near St Ives in Cambridgeshire.
Shipping: I usually ship to most destinations. If you don’t see a price, please ask. Thanks. International shipping available.
Collection: If you don’t want it shipped, I have plenty of space. If you can’t collect for a while, it’s not a problem. However, I will need to be paid very soon after the sale. Thanks.
Payment: Good old fashioned money on collection is preferred. I can accept payment through PayPal or by bank transfer as well. EUROS, I can take euros. Message me for a price and how to pay.
Import Taxes: Please note that IMPORT DUTIES are not something I can control. If you are buying from outside the UK, there is a chance that you will have to pay import taxes. Import taxes vary from country to country. If there are charges to pay, it is the buyer’s responsibility to research the cost and pay the duties. The price that you see on my advert is for the item and not the item plus whatever taxes might be due.