Kick Start

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Summary: An optional feature, Kick Start provides an additional nudge to start the motor.

Short Definition

Decoder function to help overcome motor and drivetrain stiction when a locomotive starts to move from standstill.

Kick Start is an optional multifunction decoder feature used provide additional torque to overcome motor and drivetrain stiction when a locomotive starts to move from standstill. It is controlled by CV 65.

Note: Kickstart is the name of the ROM portion of the Amiga OS. This is the result a search engine may return. For the CV65 feature, search for Kick Start.

Getting It Going

It takes more power to get an electric motor started than to keep it running; this is known as stiction. If you want to get a locomotive running slowly, you may find yourself bumping up the throttle speed and then backing it back down to the speed you want. Kick start does this for you.

With DCC, there are few ways to modify the power going to your locomotives motor (Kick Start and Dither {any others?}). Using a combination of the two, you should be able to get any locomotive started from a dead stop to nearly any speed you want - and have the decoder keep it there.

Kick Start provides an extra burst of power to get the loco started when speed step 1 is first selected. This nudge is provided for a few pulses when you first access speed step 1, then the assistance from Kick Start stops. If you've set your speed table in such a way that speed step 1 has the locomotive moving at a crawl, when the throttle is set at speed step 1 the locomotive should start crawling at that speed. You no longer need to increase the throttle and then back it down to your desired speed.

Getting Kick Start Working

Kick Start is programmed using Configuration Variable 65, and its value is determined by experimentation. By changing the value in CV 65, you change the specified amount of Kick Start applied to the motor when the throttle transitions from stop to the first speed step.

  1. Before starting to adjust CVs:
    1. Determine the CVs the multifunction decoder supports, and investigate the presence of additional CVs the manufacturer may have included for motor control purposes
    2. The locomotive in question should be well maintained, lubricated, well running, and operate it for a few minutes to warm up the motor and lubricate the mechanism.
  2. Ensure your locomotive moves at speed step 1. Get your locomotive started then back it down to speed step 1. If it stops moving, adjust the speed table or dither features first.
  3. Finding the magic number for Kick Start takes a little time. If you have speed step 1 set to keep the locomotive running, but it will not start moving on speed step 1, increase the value in Kick Start. If the loco abruptly starts, or jolts to life, then settles back down to speed step 1, lower Kick Start value. When the locomotive instantly starts to crawl at the speed step 1 speed when first entering speed step 1, you've found the perfect setting.

Kick start is usally used in conjunction with user-loadable Speed Table. It is suggested you setup your speed table before tinkering with dither or Kick Start.

System and Equipment Requirements

  • Like many decoder features, Kick Start is not intrusive to your operations. You do not need to configure it unless you want to use it.
  • Kick Start is strictly a decoder feature. Once configured, it will continue to work on any DCC system. If you use your locomotive on other layouts, there is no (re)configuration of the decoder or command station. If you want Kick Start, be sure to buy decoders that have Kick Start implemented.
  • Kick Start resides in CV 65, you must have a system or other means of programming that CV. Many of todays systems are capable of programming this CV.
  • Occasionally a manufacturer will have another feature that negates the need for Kick Start. For example, dither can take the place of Kick Start.

Notes on Various Manufacturers

As mentioned before, this CV is an optional feature.

NCE

NCE decoders have Kick Start implemented for both the resident speed curve and the user-loadable speed table. However, according to the user guide, the value in Kick Start is the number of 1/1000s of a second to "kick" the motor. This is different from the above, instead of the value controlling how much, it controls how long the built-in kick will last.

Throttle Up! and Lenz

Throttle Up! (SoundTraxx) and Lenz decoders do not have Kick Start implemented.

Further Reading

Speed Table Speed Steps