I think what the OP was saying is not that the engine runs too slowly, but that it reaches full speed at about 1/2 throttle instead of full throttle, and they want it to run at half-speed at 1/2 thottle and full-speed at full throttle. It would seem most likely it's a decoder setting that's wrong, perhaps CV6 (mid-speed) was set to a high number in error.
I think both micromark and NWSL has them. (Or had them) But they only work on open frame motors. Opening a can is likely to damage it if you don't know what you are doing.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
This is an easy fix. Either your vmax is off, or the motor isn't strong enough and your speed table needs adjusting.That said when at full throttle, does it run at the speed you require for prototypical operations? If not, you need a stronger motor.
It sounds like you have a wacky speed curve set up where it reaches full power at speed step 14 or 15 instead of 28. Maybe check CV29 to make sure it's the appropriate number to turn off speed curves, so you just use CV 2-6 for speed and momentum.
I think that the default for that Digitrax decoder is that CVs 2, 5 and 6 are set at zero. But you can check that. Programming speed on 28 steps with JMRI will help to slow it down. If you don't have that setup at home, maybe a friend or a hobby shop can help you (if you have access to one that provides that service!).
The DC71 open-frame motors can work OK, and changing the magnets with rare-earth magnets will reduce the amps required to make the engine move. But to get a really smooth performer at low speeds, you really need to change the motor.
It's not to difficult on the Bowser engines. You need to remove the worm gear (I use an NWSL gear puller), install it on a good quality can motor. You'll find these on Ebay. I like the ones sold at MicroMark tools and NWSL. Get one with a flywheel option. Just measure the diameter shaft of the old motor, and buy a motor with the proper shaft size for your worm gear. Alternatively, you can buy a sleeve from NWSL. Build a small support for your motor out of plastic, and use silicone to "glue" it on the frame. A few tries might be necessary to get the right angle. But your efforts will be rewarded. The loco will be quiet and will run at much lower speeds than an open-frame motor.
Simon
Andy.
My go to source is K&J magnetics. The last order for magnets was for four #B842 and two B841 magnets. Very inexpensive and high quality magnets. I also get under track uncoupling magnets but that's another story.
Micrmark also has a 20 piece set of magnets for $20. There's no thin magnet so you may have to shim with thin sheet metal to get the proper stack height.
Pete.
Pete: do recommend a source? Are round or small rectangles. Can I stack them?
Thanks. acutually want to try this!
Tom: Digitrax DH166, non sound. Thank you sir.
The DC71 motor is not bad out of the box. But if you change the iron magnet to neodymium magnets you'll get a motor that is really powerful throughout the whole speed range and it lowers the top speed and makes it more responsive.
Using JMRI, I found this worked on "slowing down" the overall response of an engine:
Go to the "basic speed control" pane. There are 3 sliders ("start voltage", "Vmid" and "Vhigh".
Try lowering "Vhigh" downwards, perhaps to 2/3 of the default position of "all the way" to the right. Then, put the "Vmid" slider midway between the 0 position and the "Vhigh" position.
Some "fiddlin'" will be necessary. If you don't like the results, just put the sliders back where they were (Vmid at 50% and Vhigh at 100%).
Andy,
What decoder did you install?
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
I replaced stock motor with new 5 pole skew wound motor from Bowser. It picks up current from all drivers and tender wheels. However, it reaches maximum speed at 1/2 throttle setting. The speed range is narrower than I would have thought. All CV's are factory set. What am I missing? Thanks