• heated grips kit from HotGrips
• Dremel
• drill
• wire stripper
• zip ties
• 16mm socket wrench
• epoxy or some other grip glue (optional; use if you think you need it)
• multimeter (optional)

background.
Even though I live in California, it still gets pretty chilly while riding on a winter night. Due to my tendonitis, I wear wrist braces while riding, and it was getting difficult to wear the braces and glove liners underneath my gloves. All of the layers were causing my wrists to have to work harder to bend, which made the tendonitis even worse. So, I bought this heated grips kit from HotGrips, in the hopes that I could leave the gloves liners out. The grips themselves are $90, and come with an on/off switch -- I opted for the variable heat controller for an additional $35.

Thank you to Scott Friday for his write-up, which was useful to Peter and I during our installation.

pre-procedure.
The first thing that you need to do is remove your existing grips. Depending on whether they're glued on or not, you might be able to pull/roll them off. Otherwise, break out the hobby knife or Xacto knife.

Once the old grips are off, take a look at the plastic throttle casing on the righthand grip. If you've got a SV or SVS, you'll see that there's an outer "lip" that runs along the circumference of the grip on the very end. There are also two inner "lips" on the inside edge of the plastic, close to the control switch. You'll need to dremel off all of these lips, so that the plastic throttle is smooth from end to end. Don't worry about the horizontal ridges on the plastic molding itself; that can stay.

Note: hey, shut up about that massive crack all along my throttle. This, boys and girls, is what happens when you put a long screw through your bar end, without any washers to support it inside the grip, and then you drop your bike.

procedure.
Okedoke. Here's the easy part -- slide the new grips on! We found that the lefthand grip was too easy to slide on and off -- we ended up epoxying that one on. The righthand grip, on the other hand, required quite a bit of shoving power to get on. The only thing you really need to consider when putting on the new grips is that the righthand grip will, obviously, turn with the throttle. Make sure that the little nub that sticks out with the wire won't get in your way at any point. I put the grip partially on, then turned the throttle and squeezed the brake to make sure that the brake lever wouldn't hit the nub (that's what I'm doing in the second and third pictures).

The next thing that I did was to find the placement of the controller knob. I used Scott Friday's idea of putting the knob on the left side dash, just diagonally below the speedometer. This seems to be the best place for the knob. Make sure that you don't completely block the existing hole that's there -- that's the access hole for a screw.

Once I figured out where I wanted the knob to go, I took one of the washers off of the controller stem. The inner diameter for the washer is the same as the outer diameter of the controller's stem, so I placed the washer in the correct spot, and traced the inner diameter with a pen onto the plastic dash.

Now, use the marking on the dash as your guideline of where to drill the hole. Once the hole is in place, put the controller behind the dash, with the stem sticking up through the hole. Put the washer back on the stem, and tighten with a 16mm socket. You can put the knob on now, too, if you want.

Now comes the fun part (i.e. the part that I just stood back and let Peter do) -- the wiring. I really don't know the first thing about electrics, so this section is written as though, well, as though I really don't know the first thing about electrics. Peter will probably be crying by the time he finishes reading this write-up.

The first part is easy; take the wires that are connected to the grips, and ziptie them somewhere along the handlebars, so that they won't flop around all over. Don't forget to leave enough slack in the righthand wire so that you can turn the throttle!

Obviously, the power for the heated grips has to come from somewhere, and equally obviously, that "somewhere" is the battery. Rather than just hook the wires directly to the battery, though, we decided to use the random extra connector that hides next to the airbox on the bike's righthand side. I have no idea if this connector is on every SV and SVS, but if you've got it, it seems to work. In order to make it more accessible, I removed the seat and lifted up the gas tank while Peter was stripping the ends of the grip wires.

So, now you're going to be working with four different pairs of wires: the pair from the left grip, the pair from the right grip, and the two pairs (one on each end) on the extra wire which came with your kit. Go ahead and route your wires where you want them -- the pair of wires from each grip will go to the knob controller, and the extra wire is going to run from the connector up to the knob controller.

With each pair of wires, if you haven't already, pull the two wires apart and strip the last 3/4" or so. Therefore, your grip wires will both end up in a "Y" shape, and the extra wire will look like a "Y" on both ends.

When I talked to Peter this afternoon, asking some questions about the wiring for this write-up, I could practically hear him sobbing softly from 15 miles away. In an attempt to make me less electrics-stupid, he came up with the following labelling system. Hopefully it'll make sense when I relate it here, too. ;)

The wires coming from the left grip are going to be labeled A1 and B1. The wires coming from the right grip are A2 and B2. The extra wire, which in our case runs to the connector, supplies the power from the battery, so its wires (on the end which'll attach to the knob controller) will be called Bat+ and Bat-. I'm sure the following Photoshop file will, along with squelching any doubts as to why I'm a programmer instead of an artist, clear things right up.

[Note: on the extra wire, we used Peter's multimeter to figure out which wire of the pair was Bat+, and bent it in half so we'd remember. Peter claims this step isn't necessary, that it won't matter which wire in the Y you use for Bat+ and which for Bat-]

So, now that we're nice and confused, let's start wiring things up. For those of you who will understand what he's talking about, Peter says, "the circuit basically goes Bat+ --> knob controller --> grips --> ground" .

First off, cut off the existing connector on the side of the bike, next to the airbox. Strip the two wires, and twist them with the pair that's routed up to the knob controller (Bat+ and Bat- on the other end) -- polarity won't matter here. We used wire nuts to hold the wires together, and then just tucked them into the little rubber sheath that's up next to the airbox.

My apologies for the blurry picture. I hope it's still somewhat clear what's going on.

Next, head on up to the front of the bike and to the grip wires. This is all going to be wired in series, so twist A1 and A2 together, and then twist B1 and B2 together. Look underneath the knob controller, and notice the two wires that come out the bottom. The A wire pair is going to be twisted together with Bat-, and the B wire pair will be twisted together with the knob's black wire. Finally, twist together Bat+ and the knob's red wire.

That's it! You're all done. :) The only marginally confusing thing about the grips is that the knob turns backwards from what I find intuitive -- turn the knob clockwise all the way to turn them OFF, and turn the knob counterclockwise to turn the grips ON.

Here's how the whole thing looks together (minus the lefthand bar end, which I hadn't screwed back on yet). I'll get a better picture soon, when it isn't getting dark out. In this picture, I'd turn the knob clockwise -- sort of in the direction that the narrowest part of the swoosh is pointing -- to turn the heat down, and counterclockwise -- towards the wide part of the swoosh -- to turn the heat up.