GTS300 heated grips and power outlet - fitting
This post relates how I fitted heated grips (with fully variable control) and a cigar-lighter power outlet to 'Dimples' - the GTS300 I have here in the US.

A while ago I posted about adding heated grips and a power outlet to the GTS250 in the UK - which it seems had an unusual ignition switch configuration. So this post may provide pointers for those with more normal ignition switches!

Before starting, check the seat-opener works both in the ign OFF and ign ON positions, and NOT in the LOCK position - if so, you have a 'normal' switch, and you're good to go to follow these guidelines.

The requirements were for the power outlet to be 'ON' all the time except when the switch was in the 'LOCK' position (to enable easy battery tender connection and to keep a GPS running) - and for the grips to only be 'ON' when the ignition was on.

This is easily done by tapping into wires that go directly to the ignition switch. The orange wire for the grips, and the white/black wire for the power outlet. The orange wire is fused at 15A direct from the battery, and the grips come with an inline (5A in my case) fuse which will be in series with this. The white/black wire is fused at 7.5A and only feeds the seat-opener, no extra fuse needed.

First, remove the horncast, headlight and left-hand knee-cover.

Next remove the original grips - push a long narrow screwdriver all the way through, and squirt some WD40 down the side. Wiggle the screwdriver around the bar and the grip comes off easily.

The throttle control has a lip at the end, which needs to be cut off with a sharp knife.

Now fit the heated grips to the bars - glue may be necessary, but for me the throttle side was so tight I had to use WD40 to help get the new grips on.

OK, so now to the electrics. First, remove the ignition switch, get it through the LH hole, undo the connector, then feed the wires through to the front for easy soldering etc:

Strip back the black tape, and put something underneath to catch any solder drips.

Cut the orange and the white/black wires about 10cm (4") from the connector, and kink the other two so the cut ends overlap by 1cm (half-inch).

Put a suitable length (3cm, 1.25") of heatshrink as far down the wire as possible.

Strip back the cut ends - do NOT do the usual neat twist:

Jam the ends into each other and now twist together - the orange wire in particular is a very important one - so we need this connection to be as good as possible.

Cut the supplied inline fuse connector with about 7cm (3") one end and 20cm (8") the other, and strip the longer end back about 2.5cm (1") - then twist this around the other wires:

Now solder them together, ensuring the whole joint is fully wetted, then slide up the heatshrink and shrink it:

Add a 25cm (10") length of wire to the white/black ones:

Now prepare the rest. In-line solder and shrink the +ve end of the grips connector. Then using the eyelet end of the supplied grip wiring, in-line solder and heatshrink to the grips connector and a 20cm (8") length of wire. Add 1/4" female spade connectors to wires for the power outlet.

Feed all this lot back though the LH hole.

Fit the frame eyelet beneath the fixing shown:

OK, so that's the electrics prepared - now to get the mechanical bits done.

Scribe out the inner circumference of the power connector nut onto the middle of the vertical face of the knee-cover:

And drill lots of little holes around it, centred on the scribed line:

Cut between the holes with a knife, and press out:

Clean up the mess with a knife just enough for the power connector to be a tight fit:

Mark out the outline of the grips controller:

Take off the back of the controller, and use it to be a template for the fixing holes (2.5mm, 1/8"), plus another hole for the controller wires (7mm, 9/32"):

Take off the outer shrouds of the grips connectors and feed them through the 7mm hole:

Take off the backing from the adhesive pad and fit the controller:

Re-fit the controller connector shrouds and the power connector:

Connect it all up, re-fit the panel and the ignition switch:

Now re-fit the headlight and the horncast - job done.
Last Updated Fri Nov 26, 2010 10:22 am

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