Steph 1960, your original photo shows one of the early 'peddlers' with the belt drive on the LH side. I am surprised it is listed as a 'model N' - it looks to be more in the E-G range.
Hutch, the brake shoe you have shown - if the pivot bolt is as originally fitted, would appear to be from one of the later models with the cross over gearbox and belt on the RH side. I would assume that the same brake shoe was used for both models (just the pivot bolt being reversed). This then begs the question -'were other options available' as i have seen mention of different diameter belt rims being used - thus altering the geometry of the brake shoe? - there being no provision on the frame for adjusting the position of the brake shoe.
Regards,
Eddie.
Hi Steph and Eddie,
Good question Eddie, re the different diameter belt rims and no adjustment for the rear brake block on the frame (except for the two positions on the 1914-1919 ones). I went looking through the early parts list and could only find the one part number describing the belt rim diameter for the 2 3/4 hp so far. So I can only assume that Douglas only supplied one size ? (I'm sure tho' Douglas would have supplied different diameters on request and there were probably also after market ones avail. in period) Different overall gearing ratios could be altered tho' by a selection of different primary gears for the flywheel and gearbox and also an optional variable belt pulley on the output of the gearbox was avail. from Douglas and listed in their parts lists, so maybe they didn't feel the need to supply different diameter rear wheel belt pulley's? Not sure - but will keep looking.
In my investigations I dug up some pictures of the 1913 Model N and its predecessor
to, the 1912 Model H from the Douglas specifications and Price list booklets. As usual this opened up the typical "Douglas can of worms" :-) I must admit I know very little about these models and had not really looked at their specifications in any detail before.
Interestingly the pivot point on the frame for the rear brake shoe of the model H appears to be slightly different to the model N but hard to tell accurately from the pictures. Also the brake block on the 1913 appears to have either two holes, or bolts through it? Maybe made up of two pieces of friction material bolted together or maybe the brake shoe is a different design (i.e. no slot for the block but a "T" section?? No idea and I have not found any more information so far )
Anyway, I think the rear brake system design was in a state of flux circa 1912 to 1913 and what we are seeing is most likely "pre production prototypes" ??. I say this because the way the brake operating rod attaches to the brake shoe also seems to have changed only for the 1913 model N (two adjusting nuts on the rod?) compared to the 1912 model H and all other 2 3/4hp's (the "square" type non adjustable end brazed to the rod). I'm not sure how much emphasis to place on the Model N brake picture from the Douglas Literature until more period information can be found.
After looking at the pictures I am now intrigued as to how the rear brake pedal at the bottom of the frame front downtube operates!
Steph,
I have marked up a drawing showing the dimensions of the rear brake spring I have. I did not have any accurate angle measuring equipment with me but I have estimated the position of the "spigot" to go in the frame as shown in the picture with the yellow combination square. I can get a better measurement of this if required.
If you need any more information please let me know.
Cheers
Hutch
