You have about 80W of headroom to the ragged edge limit. That said, your engine speed will need to be at about 4000RPM.

I run a vest that is rated similarly to yours. At idling speed, I have to either crank down the heat setting of the vest, or turn-off the grips to maintain charge. Cruising along, it hold charge just fine.

I also have an LED tail light, so I'm saving bout 10W there. Anyway, the loads you speak of is about all the bike will handle.

 

You have quite a bit of headroom on the circuit Neil speaks of...certainly enough for a GPS. I think it would take the same amount of time to run the outlet wiring back to the battery, though, if you don't mind the un-switched part. It seems like a 12V outlet just begs to have more and more stuff hooked to it.

There are also options like small fuze blocks with built-in relays. http://fuzeblocks.com/index.php?pid=1#board The relay runs the switched portion of the fuzes and can be energized with something as simple as your tail light wire. 'Switched or un-switched' is set for each circuit by moving the position of the fuze. The fuzeblock also eliminates having a gaggle of wires hooked to your battery terminals as you ad other accessories. Slick piece of kit

Anyway, lots of options.

 

I use my socket to charge my phone, charge my UHF transceiver and to power my small air compressor. All relatively low power devices and the compressor would only be used for a few minutes anyway.

If I was running higher power devices I would probably wire it back to the battery. And via a relay if I wanted it switched.

I like deej's idea of using the socket to charge the battery but be careful with a plug with a live centre contact. Can see that ending in tears if not handled carefully.

 

Yeah straight to the battery with a 20 amp flat fuse and holder in-line.

 

Nice GPS....great minds think alike.

 

I wonder if anyone here is familiar with the temp controller tourmaster uses on its heated garments. Specifically, werther it draws less current on the low setting, than high. I was under the impression that only a rheostat does this, and a digital controller pulls the full wattage regardless of the heat setting. I emailed Tourmaster this question, but they never responded.

I have a vest rated at 52W, that I run on low 80% of the time and med the other 20%. I'd like to add their gloves,which I believe are rated at 22W, presumably for the pair. Because the heated vest extends my winter riding range, it has exacerbated the problem of cold hands. My winter gloves are only good for the first hour, after that they're useless and burning pain in my fingers becomes the chief limiting factor in my ride.

 

Well, this is classic energy versus power. Not the same thing and often confused.

Power is an instantaneous thing. It's the load value.
Energy is power over time.
A battery stores energy not power.

Why is this relevant you ask?
Well is its battery drain you are concerned with then its energy use you need to be mindful of. But if its wiring capabilities etc you're concerned with then its load or power. If its the alternator capacity you're concerned with then it would be wise to take in to consideration both.

I don't know the Tourmaster system specifically but I would suspect it uses pulse width modulator to control the vest. By switching the vest element on and off, and controlling the amount of on time versus off time, you will control the temperature. But at any given moment the current draw will either be maximum or zero. Thats how a light dimmer usually works.

So, in one way the load is the same regardless of what temp setting you have, but, the load is switched on for a shorter period of time so you use less energy over time and the vest will not get so hot. This switching happens many times a second. Its a far more efficient way to control temp as the energy loss is minimal.

If there is a thermostat or some other temperature sensing method used, then usually full power is applied until the nominated temperature is reached and the load is switched off. The switching here is sort of similar to the pulse width modulator described above as in it's the average load over time that is determining the energy draw and therefore temperature, but the switching frequency is much lower. Interestingly the on/off or mark/space ratio will be the same.

In summary a digital temperature controller does load the system the same amount regardless of the setting chosen but it does it for less time so the energy used is less.

Sorry for the ramble.

 

That makes perfect sense, like you said, if it's a pulse width modulator it must be switching on and off many times per second as the heat output feels very even. Without a response from Tourmaster, I guess the only thing to do is give the gloves a try and hope for the best.

 

Post up more pics, specifically of the wire splice or battery terminal hook up.
I like the switched power point. I would leave something on, and drain my battery.

 

and... why is that?