Hi, if anybody wonders: why isn't my loco pulling more coaches or wagons ?
there are several reasons for it:

weight
ruber tyres
amount of rubber tyres
oil
dirty track

the main culprit is of course oil, over oiling is a standard habit for many train enthusiasts and this leads to many problems

a.) the rubber tyres extend and loose traction
b.) the tracks get dirty with grime and oil
c.) the armature gets filled with graphite

extra pulling power:

one can add more wheels with rubber tyres if needed, however this is more difficult with older locos whereas the axles are embedded in the frame and most the time can only be changed with a special tool.

ratio between the loco and motor: for most of its existence, motors have been strong enough to pull heave trains and earlier models such as fully metal locos combined with weight have proven so.
over years more plastic has been introduced and the locos got lighter and lighter and the actual driving axles has been 2 on electric locos regardless if they are Bo-Bo or Co-Co., all your earlier Co-Co locos, e.g. BR 103, BR 194, BR 151 etc etc. the middle axle had no contact with the track at all. most of these locos had 4 rubber tyres restricted to on 1 bogie.

than newer locos arrive on the scene with both bogies powered but now we only have 2 rubber tyres, 1 each on opposite sides of both bogies.

so what is the difference ? the weight didn't change much, the power drives are now on 4 axles but we only have 2 rubber tyres. whether or not the motor itself is weaker I don't know but its definitely smaller.

so manufacturers have played with the ratio from weight - power by introducing all wheel drive, decoders who can manage the motor output but at the same time restricted the power ratio by reducing wheels with rubber tyres.

what is also astonishing, some of the Traxx locos only come with 2 rubber tyres and if you want to increase the wheels with rubber tyres you have to buy a whole axle (1 rubber tyre) for Euro 30.00 whereas the loco itself you can pick up for under Euro 100.00.

Until I get all my tacks finishes I'll be able to test the difference between 2 or 4 rubber tyres on these Traxx loco and see if it makes any difference and whether or not the motor can cope with it.

I assume for most of you this is may be a topic not many of you are interested in, so long the train or loco runs on tracks from point A to point B and satisfies some of nostalgia or relaxation.

my interest lays more in the performance of locos, their role as a prototype and the difference between prototype and model if any.

I've noticed in the early days of my interest in model trains, the importance it was, to understand the prototype loco and its history, its performance, its weight etc. etc. and as children we all got hooked on it, one day we can buy one of these legends and take them to their task but it didn't last for ever, with some models have made their way to its present day: SBB Ce 5/6 for instance., Roco had produced one for years but its pulling power is dismal. (tender driven).

so what has changed over the years ?
models got more precise, metal parts are no longer the main issue, plastic add on parts are now fully acceptable, prices don't seem to be an issue either., rubber tyres ? can't hear anybody complaining about it, weight seems to be ok. new motors: some resistance and driving shafts on all 4 axles seems to be also well accepted.

So what seems to be the problem ? my issue is the performance of a model compared to a prototype, everything looks like in place: the details, the accuracy, the weight, all wheel drive, new motor except enough rubber tyres which would bring any loco much nearer to its prototype.
All the advertising we see and read is about how a particular loco performed over years and years. for instance the Swiss crocodile, the BR 194 over the Geislinger Incline, the BR 44, BR 151, BR 191, BR 96 and many others.

I don't think we''ll ever see any of the new electric locos, like another 3015 crocodile appearing not for its oversize but for its weight, whereas a Roco loco is heavier with a plastic body than the Märklin model all metal,
are we becoming more feminist and only go for good looks ? or is there still some grunt and guts in us whereas one day we see a new item has all the expectations for all of us.
anyhow its good to have a good old whinge on a Monday, it keeps the air clean for the rest of the week.

what are your thoughts ?

regards.,

John

thanks for the links, very enjoyable.

The Queensland coal trains on the Coppabella to Mackay route (1067mm gauge) used diesel-electrics, 5000 tonne, two locos at front, 2 at rear, and one in the middle called a mid-train helper. This loco and the rear locomotives were controlled by a radio link to the front driver locomotive.
Now they have switched to electric locomotives, and I don't know how they deploy them on the trains, because I have not been in that geographical area for nearly 20 years.

Regarding my Marklin locos I have never had any trouble on my level layout with adhesion.
I sometimes test the pulling power of a locomotive and I cannot supply a long enough train to cause it to slip or not pull the train.

Kimball