S6 & T6 models

[graeme]

Hello All

Can anyone enlighten me as to whether the frame and engine for the S6 and T6 machines are identical? I know that the forks are different, plus other cycle parts like carry rack and toolbox, footpeg arrangement etc.

Thanks.
Cheers, Graeme

[MRD]

 Graeme
It is my understanding that the basic engines were the same, with differences being on the flywheel sprocket.
The gear box had many different ratios which were sports solo, sports sidecar, touring solo and touring sidecar. Plus 3 and 4 speed gearboxes.
The exact ratios can be seen in latest edition (Nov/Dec 08) of the New Conrod, page 13

There was one difference that I know of although I'm not sure if it was specific to any particular 600 model. This was a side carburetter rather than the common updraught. Now I can hear people shouting at there computers saying that was on the 750 model! but no Mr Douglas also made it for the 600 motor. this was slightly shorter than that of the larger capacity model. It just happens that my brother has one of these manifolds for his T6 and there is no way it would fit the 750.

When I originally got my S6, a long standing member of the club approached me and said "If you want it to go faster then change the inlet cam for an exhaust cam"
Unfortunately when building my bike I never found a second exhaust cam gear so I was unable to try it .
Perhaps some out there has done this and let us know how well it went.

The frame on the T6 had a lug on the back of the steering head so that the steering damper could be anchored where the S6 had a cone and cup type of damper which went through the stem
I hope this is helpfull
Regards           Martin

[Doug]

The 1931 edition of the spare book lists the crankcase, crank, sump, and contents of the timing chest as interchangeable. Differences came into play with the cylinders and the flywheel clutch. At that point in time (pre-750) there was only one timing cover and carburetor offered.

-Doug

[graeme]

Thanks Martin and Doug
The reason for the question is that my young nephew is attempting to collect enough parts to put together an S6, the major thing missing so far being the entire front end. I was wondering if we perchance happened to find forks etc for a T6, whether the machine could morph from an S6 into a T6. By the sound of it this is entirely possible. I have never seen a T6 in Australia, so pretty unlikely to find parts in any case, but worth asking.
Cheers, Graeme

[Doug]

Graeme,

As you probably know, the T6 and E31 used the old style forks (600EW) with the twin extension springs, though the blades were a little longer to suit balloon tyres. So they also used the old style steering stem with the sockets for the lamp holder brackets. Consequently, as Martin pointed out, there was a different headstock on the T6 frame. So you may not be able to put a T6 stem into a S6 frame, depending on the differences in diameter and length.

I could check the dimensions of a S6 stem readily enough, but the EW600 (in lieu of a T6) would entail disassembling something. That is not going to happen, as I have too much apart as it is! 

-Doug