imported post
If you can get under the skin of the saddle it can easily be done. All you'd need isabout 20 to 30 feet of #30 AWG stranded, teflon coated wire (as the heating element), and associated connectors, switch, etc. It's important that the wire is stranded because if it's solid it will quickly break. This is really, really tiny wire.
The biggest challenge is to provide strain relief for the tiny #30 wire... although flexible, it can break easily under tension.
Here's how I'd do it... I've never done a seat, but I have done jacket liners.
Remove the seat vinyl.
Use about 25 to 30 feet of the #30 wire and run it back and forth, evenly spaced,over the seat foam to cover the whole thing. Use tape to temporarily hold it in place.
Solder a length of thicker wire (#16 or so) to each end of theelement wire,then insulate the connectionswith shrink-tubing (these will be the lead-in wires). Anchor the lead-in wires ina way so there is no chance that they will pull on the element wires. Use enough of the thicker wireso you'll be able to tap into wherever you'll eventually get power and installyour switch. Plan ahead so the lead-in wires come out of the seat where you want them - preferrably in a place where they will be protected from abuse.
Spray-glue alayer of clear plastic sheeting on top ofthe saddle foam and wiresto keep it waterproof and stabilize the thin wires, then install the skin (vinyl) of the saddle.
Now all you'll have to do is figure out where to place the switch and where you'll get power.
This arrangement will draw about 3 amps. That's enough to quickly killyour battery if the engine is not running. For this reason be sure to tap in where the power is turned off when the key is turned off. Also be certain to protect the circuit with a fuse of around 4 or 5 amps.
This setup is pretty much a short circuit, but since the small wire has so much resistance, the electricity is released as heat. This is the way all electric jacket liners, grips, and seats work. A lightbulb works in a similar way, but instead of just heat being released, light is also being released.