classic motorcycle forum

Hello Pat and Rich,

I agree - a most unusual machine, and almost certainly an NSU.

Note that it's a slightly different model than the one shown on 3wheelers.com. While that one has the 2-speed gear and clutch in the back hub (perhaps a ROC hub?), the one here has the NSU 2-speed gear and clutch on the engine pulley. The gear is operated by the vertical rod passing through the "N" on the tank to the little tram handle on the tank top. Wind it one way for low gear, then the other for neutral and then top.

Regardless of the exact specs of the machine, it's a most atmospheric photo! Thanks for posting it.

Leon

Thanks for the positive comments - I'm please you enjoyed looking at the website. I designed it for a leisurely browse.

Just to finish off with this photo. I checked the registration records and 11816 was issued to H.K. Scott of Currency Creek (a rather isolated spot about 80 km south east of Adelaide) in June 1918. By then the bike was about 7 years old. Plenty of time to do those sporty mods!

Leon

I think if Murray gets a bright light and a magnifying glass he might read "New Hudson" on the tank.
New Hudson went in heavily for the enclosed look in the early 1930s (lots of pressed metal enclosing the lower half of the motor and gearbox) so I suspect this example is from the late 1920s. Probably a side valve 500 from about 1929?
It's a handsome bike - a pity about the antiquated carbide lighting set!

Cheers

Leon

Hi all,
What a fascinating hobby we have - almost an infinite amount of hardware to contemplate - consider the range manuacturers around the world at different times, then add in the backyard fiddler who modifies this and that to suit needs or preference. Personally I like looking at old bits, photos or whatever, and it's particularly satisfying when we learn something from the exercise.
I wonder should we revisit some of the thoughts in this thread?
Our original poster Peet_K asks what he's got, posting a clear photo and telling us it has "New Hudson" on the seat. Peter C replies "It's a Triumph C-Series frame (Models CN, CO, CSD, CTT) from 1929-32." This sounds pretty defintive - Peter tells us the frame IS Triumph, no ifs or buts. He doesn't say "highly modified", "slightly unusual" or anything like that.
Our original poster, probably having been to Peter C's web page where the C model is described http://users.actrix.co.nz/cornelius/Triumph/ModelCN.htm , notes that it doesn't look too much like any Triumph that he has seen, and posts some more pictures (interseting punch set used for the frame number!). ColinB seems unhappy that the triumph specialist could be doubted (and asks Peet_K what he thinks it is - he doesn't know, that's why he posted!), and m3bobby states uncategorically that "its definatly Triumph" but explains the major modifications where the frame has been cut and shut.
Peter C. finishes off with "it's now a Nothing frame, and worth the same amount", which seems quite a shift from the previous day when it was a Triumph C-Series from 1929-32.
I wonder where this leaves Peet_K? Has he learned anything? Have other forum mebers learned anything?
Unfortunately I don't know a lot about early 1930s bikes, but  I do know that the frame is quite unlike the Triumph C-series frame as shown on Peter C's webpage, but perhaps Peter C or m3bobby can tell us more. As to being worth nothing, quite the contrary! Good bits here, if only we can identify them.
Leon

Hi Rod,
To give you some idea, an 8 h.p. (say 1000cc sidevalve twin) motor in an early motorcycle would be geared at around 4:1 (4 turns of the engine for one of the back wheel) in top gear with wheels of rolling diameter 26".
Your proposed 14/42/14/42 gearing would give an overall ratio of 9:1 in top gear (1:1 in the gearbox), so it would be very low geared. But then you have to carry around 3 wheels, and the B&S might turn higher revs than an old twin. Some experimenting will be required!
Leon

These days old carburettors are often built from slightly mixed collections of parts, so we have to do the best with what we have!

My AMAC book gives model T. 15MDY and T. 15MDX as 1928 touring models with bottom and top feed float bowls, respectively, so maybe the "4" you quote is a mis-read of X or Y? Equivalent 1926 and 1927 models are PJY and PJX. "15" refers to 1 1/8" throttle valve - sounds about right for a sv 500.

Anyway, the plan should be to get the fuel level just below the top of the jet. From your description it sounds like this can be done - even if you need to modify the notch on the float needle or the clip on the float. An easy check for about the right fuel level is that the carb shouldn't drip if the bike is upright, but begins to drip if the bike is leaned over away from the fuel bowl. Test this with the throttle open (no needle bocking the main jet) but the engine not running!!!

Hope this helps. I can copy the parts list, but I doubt it would be of much use.

Leon

Hi Graeme,
not sure what kind of info you are looking for but Sloper magdynos must have changed a bit over the 1927-1935 span of the model. Vintage ones (and perhaps a year or two into the 1930s) used the one-piece alloy-bodied three-brush Lucas magneto. These early ones lacked the clutch between the drive gear on the magneto shaft and the dynamo armature, so they tended to shake themselves to bits. When you see them these days, the bodies are often damaged where the generator armature has tried to escape through the end of the case! Like most Lucas products, the magdynos are stamped with the date code: 930=September 1930 etc.
Leon