I noticed that the 39745 in the Marklin parts diagram shows only the fourth axle (counting from the front) is geared to the can motor. The spur gear on this axle is at the center of the axle and equal distance from either wheel. Lately, Marklin is using can motors and the pinion gear is at the center of the chassis and so the gear on the axle has to be equal distance from the 2 wheels. You will notice a bulge on the red plastic on the underside when you turn the lok over. The bulge is where the spur gear is.

I have the older 3084, also a BR50 and if you look at the parts diagram on the Marklin website, all 5 axles are geared together with the spur gears.
Swapping axles with a gear on it will be difficult as there is no bulge in the red plastic frame for the first axle. Also, connecting the driving power from 1 axle (with rubber tires) to the next axle (with rubber tires) using the coupling rods may not work well.

Maybe you will just have to run 2 of these loks together in tandem to get more pulling power.

I run 2 of my 3084 together and they look beautiful running together.

I was referring to the newer Märklin BR50's that are much like the BR44's, except the new BR50's have traction tires on the 1st axle and the 4th axle.

I also double-head 2 BR44's in long trains; but shorter trains shouldn't require 2 loks.





No such thing as a stupid question.

All of my BR44's are less than a year old. The main problem with traction is when there is any change of grade in the track; no matter how subtle it is. Since the traction tires are only on the 4th axle (out of 5 axles), any change of grade in the track lifts the 4th axle up and it loses traction. The BR50's don't have this problem since they also have traction tires on the 1st axle.

Does not seem like mârklin sells the wheels for the new Class 50 as spares?. Try a search on eBay or contact Märklin. Assuming you have measured the wheels?.

I noticed the 44 are listed with 7153 traction tires, and the 50 are listed with 7152.
So you could try some 7152 on the 44 and see if it helps. Less stretch should give ticker rubber and potentially more grip.

One other thing you could try is the reduce the spring tension on the 5th axle or test with shorter springs or possibly without it?. Ref drawing and part 23 on the 39745. That might help to shift more weight onto the 4th axle. could also be that the spring is slightly too stiff on the other axles?
(I have the 39745 but not a modern br50, and have not taken it apart.)

Hi
I reply to this thread a bit late, sorry.
Pull power is more efficient when the wheelset with tires is located behind so that during a pull effort the force pushing on the tire will increase.
Märklin also avoids using gear train on all axles on steam locos , using the coupling rods instead BUT, these cannot transmit a lot of force so, often, the geared axle is also the one fitted with traction tires.
In recent steamer designs, Märklin uses TWO unsuspended wheel sets (axle 2 and axle 4, more precisely the second and the one before last) when others are suspended and with lateral play. This means the other axles are there for cosmetic purposes AND current pick-up (but almost no traction force is to be expected because there is no apparent weight on them.

Sorry for the big speech, but the number of tires is reduced to improve the contact wheel-rail as often only one of the rails is delivering voltage while the other is for occupation detection. In your case, the last wheelset is not getting the weight of the loco but the one with traction tires (so adding more wheelsets with tires wouldn't do much is getting the weight UNLESS your track is not smooth vertically (a vertical angle between 2 track pieces).

Also recent tires have excellent adherence qualities (must throw away the old one you have since years in your spares drawer making the pulling power quite sufficient BUT (1) start and end of ramps must be CURVED and NOT use the play between two rails. On C Track this is best made by cutting vertical from the bottom of ballast using a dremel-like (Proxxon) tool and a diamond disk and (2) the tires may dry with time and need replacing (not your case, I think) or be spoiled with lubricant or smoke oil. Solution: clean with Isopropyl alcohol and a ear bud while the loco is upside down on a foam bed with power connected to it and a run command.

Cheers
Jean