Quote from: dalgrae on Yesterday at 12:35Hi,Brit Bits in Christchurch did have some new jet blocks ,if that helps


Colin

Thanks Colin I'll give them a call tomorrow 

Hi,Brit Bits in Christchurch did have some new jet blocks ,if that helps


Colin

Hi, no I don't have a spare jet block . However, if you do have a spare it would be advantageous in finding out the problem so I can send my carb away to be refurbished. Alternatively, if you're quite sure I can send it away anyway. Thanks for your kind offer

Hi Andrew and welcome to the Forum!

As far as I know the front and rear TS hubs are identical. 

Having a quick look at the 1916, 1922, 1924 and 1925 2 ¾ HP parts booklets and it appears that there are some typos on the pictures of the parts, some of the parts changed over the years and also one of the felt washers became obsolete (the one under the screw on dust cap). 

I took a picture of one hub I have and marked it up with the best version of the part numbers I could work out for 1924 – it was slightly ambiguous and may not be 100% correct but hopefully will help you out.

(The Spare Parts List of the Douglas Motorcycle 2 3/4HP – If you don't already have a copy of one of the later versions of this it can be obtained from a number of sources such as The London Douglas Motor Cycle Club, Bert Pol etc. The most common one appears to be the 1925 version)

I have also attached some pictures of the parts list from 1924 for the wheel group.

Note:

·       The right hand thread cup (RH) threads in all the way into the hub and tightened. These can be quite hard to get out and may take some patience.
·       The left hand thread cup is the adjustable one to set the play on the bearings and locked by 1309D.
·       Some hub cups have 4 small holes in them for the pin spanner used to screw them in or out, and some have 6, as long as they screw into the hub ok it shouldn't matter.
·       The balls are not shown in my picture. All the hubs I have seen use 5/19" balls rather than the ¼" listed in the parts booklet. There appears to be 18 5/16" ball used – 9 each side.
·       The outer dust covers 1397D and 1398D don't seem to have survived very well and are often missing / hard to find – great if you have some to fit tho'! They are just pressed thin steel sheet metal.
·       Likewise, the lip washer for the wheel spindle, 1404D is often missing. I think at one stage these were available from the club or Bert Pol. Not sure if they still are. I think there maybe some repro ones available if you don't have any but are easy enough to make if you had to. There was a thread on this topic here;

 https://www.douglasmotorcycles.net/index.php?topic=9251.msg36514#msg36514
 
·       Some of the very early versions of these hubs do not have the inner screw on dust covers, this feature seems to have been introduced around the start of WW1. 
·       How the wheel / hub is mounted in the forks / frame is important. This has been previously discussed on this forum. There is also a cross section of the hub in this thread.
https://www.douglasmotorcycles.net/index.php?topic=9319.msg36868#msg36868


If anyone sees anything amiss with my picture of the 2 3/4hp hub parts or has any info. to add, please post here and/or let me know and I will fix it up – I'm still learning about this topic 

Apologies for the longish post but please let me know if you need more information and best of luck sorting out your hub parts!

Cheers
Hutch

If the jet block is slack, there would seem to be three likely culprits, the first is that the carb body is worn or distorted, or the second that the jet block is worn and finally a combination of both, do you have a spare jet block to try, or compare the one in use to. If not I think I may have a spare block you could borrow unfortunately not sure where it may be, will have a search tomorrow to or Monday and let you know. 

Just an update.  Please find photo dated 1956 mentioned previously for interest.
Logbook shows first registered January 1923, which goes with the comment from Hutch about the 23/24 model having the mounting there.

Quote from: eddie on 23 Apr 2025 at 12:53 Providing that small drilling connects to another drilling, it should be OK. Regarding the fibre washer under the let block - the original was of a soft material that often disintegrated as the base nut was unscrewed. It can be replaced with a red fibre washer, but it needs to have a large bore so that it doesn't obstruct any drillings in the base of the jet block. While you have the jet block out, check that the small drilling in the bottom of the main bore of the carb body is also clear. The drilling is at an angle up from the slow running screw into the main bore.

  Regards,
              Eddie.

  P.S. The jet block fits direct against the bottom of the carb body - there is no washer needed between the two.

Thanks Eddie. After swapping carburettors the problem switched to the other side. First I checked carburettor body holes and all were clear. Anything else you can think of? I can get the carburettor refurbished to fix the loose jet block etc. which is all I can think of

Quote from: yosemite on 19 Apr 2025 at 22:32 Have you tried swapping carbs from one side to the other, if the fault migrates then the problem is with the carb if not the problem lies elsewhere.

Hi Yosemite, yes, just swapped carbs around today and the problem migrated. I have cleaned thoroughly jet block holes and the holes in the carburettor body, all clear. The only thing I can do now is send the carburettor away for refurbishment and get a sleeve put in for the loose jet block. Any other ideas? Thanks 

Thanks very much for that Hutch.  The needle valve fitted a treat.
Also found an old photo of father-in-law on the m/c dated 1956 at a local club day and the generator can just be seen mounted below the saddle behind his leg.  Failed to find anything resembling the support bracket but can make one up to enable all the parts to be assembled.
Have attached recent photo with parts together for interest. No sign of any rear light ever fitted and saddle mounting is unlike any other pictures seen of similar m/cs.

I am assembling all the parts to pass the m/c on, as a couple of strokes have left me unable to do much with it.

Many thanks again for your help.

Looking for measurements to construct a side car chassis to suit 1927 EW Douglas 350cc which I intend to fit a tradesman box to
Regards LBHill