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         The later (Mk4&5) shock absorber cover had 3 cutaways to clear the front 3 final drive mounting studs and nuts. It is also interesting to note that there is no mention in the spares book of these studs having washers under the nuts. Added to this, the depth of the cutaways may need to be altered depending on the number of adjustment shims required between the gearbox case and the final drive housing. These shock absorber covers are quite prone to damage from broken chains, etc., so it is quite possible that yours may be a repro casting supplied at some time by the LDMCC spares scheme. With all this in mind, the cutaways may need easing so that the cover fits snugly to the face of the final drive housing. The shock absorber cover is not intended to keep all the weather off the final drive - it is there to prevent trousers, fingers, etc. from being caught in the chain, and also to prevent the chain from throwing oil/grease onto anything in it's line.

Hi Michael, thanks for reply. Photos attached.  I have ringed where parts of the cover have been cut out to clear the middle and  lower stud nuts of the final drive housing, although a spacer was fitted on the bottom cover securing stud because the top of the cover was still contacting the foremost top final drive housing stud nut as this one had not been cut away. I have removed the two studs which secure the cover as these were incorrect anyway, one was just a threaded rod and they were not in straight so the cover would not pass over the studs. These two studs do not go into a blind hole but through and into the gearbox. I hope you can follow this. Paul J

Images converted to linked files - Dave, 01Dec2021
Hi Paul,

there is a different cover for the MK1 model. A photo would help to identify your cover.

#2. Does anyone know what size the pilot jet size should be.
The main jet was probably about 0.031".

Douglas Motorcycles - General Discussion / Re: D28 B&B Side Draft Carburetor
« Last post by eddie on 29 Nov 2021 at 10:15  »
Maybe someone, at some time, has fitted a slide from a different carb. A similar situation exists with later Amal carbs - the series 4 and 5 carbs have identical slides except the 5 slide is longer overall than the 4 slide, so wont give full throttle if fitted in a series 4 carb.

Hi Don.

Found this site useful for jet sizes and general info regarding B&B carbs:

Slide not opening fully can't be right, as it may as well just have a smaller choke diameter. The B&B on my EW is vertical, but around the same size as yours, and the slide(s) definitely open all the way.

Cheers, Paul
Hi, the shock absorber cover on my MkV will not fit flush up to the final drive housing of my gearbox. One of the six nuts, this one being  the top foremost next to the longer stud that holds the shock absorber cover on, stops the shock absorber cover from butting up against the final drive housing, so the final drive sprocket and spring will be open to the elements. There are two apertures on the cover for the middle and lower stud nuts which have been crudely made to be able to bridge over them. Have I the correct cover? Or maybe the nuts which fit on the studs are too large of external diameter. Please advise, all appreciated. Thanks, Paul J
Douglas Motorcycles - General Discussion / Model Z frame damage
« Last post by saluki42 on 28 Nov 2021 at 10:15  »
Hi I have a question regarding some historic damage done to my 34 Model Z frame. The damage is to the front lower casting connecting the down tube to the engine mounting lateral tubes on the drive side. As you can see from the attached picture somebody in the past appears to of hacksawed away a section of the casting and I was wondering if anybody can think of a logical reason why this may have been done.
I'd be interested to see your opinions on this.

Douglas Motorcycles - General Discussion / Re: Ew350 gearbox bearing
« Last post by Neilj on 28 Nov 2021 at 09:48  »
Thanks does seem tight thatís why I thought Iíd ask the question.Will try gentle warm and releasing fluid.cheers
Gday All. I have a couple of question regarding a D28 B&B side draft carby.
I canít see any size markings on the body, have measured the internals and have the following dimensions. Slide hole 0.920thou, outlet venturi is approximately 0.740thou and the mount spigot is 1Ē.
I made a new slide for it as the old one gas completely worn out.
# 1. Should the Slide fully uncover the venturi? Only opens 2/3 then hits the cap. The new ones is an accurate copy of the old of course. See photos for fully open and fully closed positions.
#2. Does anyone know what size the pilot jet size should be., I know they are sized by flow but I need a starting point. As you can see from the photos there was no idle jet just a needle?
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