Hi Michael, 

That's good to find proof, it does make sense not to blow exhaust gas onto the back wheel!
A photo would be great and if you can take some overall measurements that would be even better as I have scaled the fin from the photo, which is not the most accurate way.

Thanks again
Tony

Hi Tony,

several years ago I bought a 1930 Douglas H3 in bits and pieces with an "exploded" engine, several bits missing. So there was also no silencer for the bike (I'm still looking for a good one).
But in that convolut there was also a single fishtail for a Douglas Bantam. It´s a left side tail and there are NO HOLES on the inside of the tail.
If you like a photo, please let me know.

Michael

Hi Eddie
Thank you soooo much for your detailed reply.
I did not look at the main bearing. The thrust race was in position. I did notice the one of the 3 springs holding the thrust race is R/S.
I would like to think that I have the experience to follow your instructions - but I doubt it!
I gather the problem can be fixed without a total rebuild, so I am prepared to have a go.
If I fail, then I hope to find a Douglas guru who is prepare do to it for me.
The last thing I want is to make the situation worse.
I did notice that the clutch operating arm is fully jammed on the crankcase. There is no gap between the lever and the crankcase.
I have a couple of weeks of WORK! before I can tackle it again.
This forum is fantastic!
Thank You again.

Best Regards,
Gary Anderson

Hi all,

I am making a press tool to produce the tail pipe for the 1933 Douglas Bantam which is missing on my bike.
Does anyone have an original one so that they can let me know if the side holes are on both sides of the tail fin or just the outer face.
Would anyone be interested if I made some more, as I notice that on images found on line that they are missing.
Images attached of my Bantam, original factory photo of the 1933 model and close up of the tail pipe showing the side holes

Thanks Tony 

Hello, Alan.

Thanks for letting me know who can repair my Douglas crankshaft!

I found a repairer in Japan for the ew600 crankshaft.

I was also looking for a repairer for the Douglas d31 crankshaft.
I am contacting Alpha Bearings.

Thank you kindly.

Yoshimasa Negishi

Gary,
        I think you may have 2 problems with your engine. Firstly, when you replaced (and fully tightened) the flywheel, was there any shims between the rear main bearing and the clutch release spigot? If so, you will need to remove the flywheel again, tap the crankshaft and rear main bearing forward as far as it will go, measure the depth from the back of the crankcase to the face of the rear main bearing and subtract 5 thou. Now measure the depth of the clutch spigot, and make up shims equal to that figure, then re-fit the clutch/flywheel. Having done this, operating the clutch will just pull the crankshaft and bearing back against the clutch spigot (without loading up the thrust faces on the front main bearing).
    The second problem (slipping clutch) may be caused by a worn coupling on the gearbox. I had a similar problem on my Dragonfly - the clutch would be fine with a cold motor, but after about 10 miles, clutch slip would get gradually worse until I let the motor cool down again. On inspection, I found the coupling was worn and was trapping the clutch plate so that, effectively, only one side of the plate was actually doing the driving. Just grinding back the 6 splines on the coupling to remove the step cured the problem!

  Hope this is of some help,
                                       Regards,
                                                    Eddie.
P.S.  When you re-fit the flywheel, check that you still have some free movement on the clutch operating arm and that it is not bearing against the inside of the bellhousing. (The lever is in 2 bits and can easily be adjusted).
P.P.S.    A couple of other things to bear in mind. As you turn your engine. you will notice 'tight spots' caused by the resistance of the valve springs as the valves open - that is normal.
   A similar clutch problem to yours came about when we first went over to asbestos free linings - the early type linings were made of a grey composite material that was a good friction material but it gave off a fine dust that collected on the pins through the flywheel, causing drag. The later woven material (like the old Ferodo) is much better in our clutches.

Hi Everyone,
My name is Gary Anderson from Wollongong Australia.
I have finally bit the bullet to change the slipping clutch in my MK4.
I installed a new clutch plate and everything looked good, but when I tested the clutch in the frame it was obviously still slipping.
Dismantle the clutch again and find the pins are not sliding evenly through the flywheel.
Cleaned everything and again everything looked good.
I replaced the flywheel on the crankshaft and tightened the nut. It was previously suggested that I use an impact gun to ensure the nut is tight.
I have read somewhere that doing this may pull the crankshaft to the back of the engine resulting in crankshaft misalignment.
I think this has happened to me in this case.
Even without plugs the motor is very tight to turn over by hand. The tightness seems to repeat in specific areas of each rotation.
I am afraid to attempt to start the motor in case I do even more damage.

Any thoughts, ideas or recommendations would be greatly appreciated.

Thanks,
Gary Anderson 

 

Hi Yoshimasa,  I have had a T6 crankshaft rebuilt by Alpha Bearings -
info@alpha-bearings.com.

My T6 is a 1930 Douglas. It looks like the same as yours.

Regards Alan Reid

They'd have to be forged/pressed onto something like a broach anyway  ?

You could possibly heat the kickarter until it was soft, and tighten/clamp it 
down enough on that tapered spline until it conformed enough to hold.
And trust that it didn't degrade the spline teeth ?

I've used a triangular file to recut some spline teeth - in desperation !
Not a tapered variety though, which adds a whole measure of complexity...

They can also be forged/pressed, which is I suspect how Kingswood did it. I did this for the 3-speed, small tapered spline. See this post HERE.

It probably ended up being just as difficult as cutting the splines...

-Doug