Sparky got a comfort mod, with the installation of Cycle Gear heated grips. The budget $20 on sale version. Since I had plenty of extra wire to make all the connections and I wanted to keep the Pillow Top grips, I chose this labor of love instead of going with a complete package like Oxford.
First step was to figure out the wiring as the grip heaters came with limited instructions. I used the Black/White wire behind the headlight as the ground connection. Then I used the Blue/White wire from the headlight relay as "Control" power. This relay is located on left side of bike to the rear of the bike, or just about 8" to the right of the battery. Its tucked up tight along the frame. "Control" power is routed to 87 on the relay ($7 Auto Zone). This power energizes the relay and allows the "Operating" power (30 on relay) to flow. Like a light switch turns on the light, the relay is turned on. The headlight relay wire I used Blue/White is only energized when the engine is running. A neat feature of the WR250R wiring design. So the heated grips will only work when the engine is running. The "Operating" power is taken from the battery with in-line 7amp fused link, that I had as left-over wiring. I replaced the cheep plastic hi/low switch with a rubber covered 3 position switch from Rocky Mt. ATV ($5), and while I was there I got two small green LED's for another ($5) and new set of Pillow Top grips ($12).
Next, I needed a location to mount the rocker switch, and found inspiration from Highway Dirtbikes handlebar mounts. So I bought a small galvanized plate at Lowe's ($1.14) and commenced to shaping. This process took considerable amount of time and patience working with hacksaw and small dremel. I also need a place to mount the resistor that comes hard wired to the grips. This resistor turns current into heat and reduces the current to the "low" side of the grip power. It gets very hot (measured @ 150°) and should NOT be placed next to anything that might melt !!! So I chose to mount it inside a small metal pipe ($1) with some JB Weld ($7). I mounted the resistor/pipe assembly under the handlebar crossbar with a pipe clamp.
With everything wired up I was able to test function. The heat output 94° on Low and 114° on High. Some choose to not wire up the Low side of the grip heating and eliminate the resistor heating thing all together. With my thin Pillow Top grips I wanted both settings to work and thought I would pass on some actual heating measurements. Everything worked, so was time to mount it all up and tidy up the wiring. I put a zip-tie around the grip wiring connectors to help keep them in place from possible movement. I used some heat shrink tubing around the two throttle side wires to make it stronger as they move 1/4 turn with throttle use.
I ended up making a few modifications to my switch mounting plate as the first one was a bit too large and blocked view of the instrument panel. I mounted a small voltage meter inline with the turn signal indicator LED's. I ditched the HI/Low indicator plate as this is a trail bike and I like the simple unlabeled look, and sprayed the plate with a few coats bedliner paint. I used a small section of old inner tube to form a shield in front of the plate where the switches were exposed. Even though I used water-proof connectors and shrink wrap tubing around them.
Here is the final Aux-Dash. Unobstructed view of OEM dash. Hole on right side of voltmeter is for another switch to operate Aux Driving Lights in possible future mod. Everything worked over the recent 2-day, 550 mile ride:
http://www.twtex.com/forums/showthread.php?t=112821
All together it cost about $60 for this mod. I probably got a little carried away with the turn signal LED's, as I still leave them on at times (ha-ha). They have glass lenses and can sometimes be hard to see in direct sunlight. The WR voltage ranged from 13.6-14.1 and is nice to know. The grip heat on "Low" was perfect under my Pillow Top grips in mild 60-70 degree temps and thin gloves. What a comfort to have my hands warmer than my face. On the "High" setting, they were very warm and heat the stock steel bars up quick. I soon turned them down to low, but think they will be great in 50° temps or below on those high elevation BDR sections. As mentioned earlier this really was a "labor of love" as the 2hr install turned into more like two days. But, I must admit the satisfaction of custom set-up is very rewarding.
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