Keeping her hands warm – by Frank firstname.lastname@example.org
The Germans (BMW) and the Brits (Triumph) know that warm hands make happy riders. Both companies offer heated grips for their bikes. Somehow Japanese manufacturers haven’t yet discovered the cup holders of motrcycledom. As a BMW owner, I’m aware how much more comfortable it is to ride in the winter when my hands are warm. For Christmas my wife got a new Suzuki SV650. She wanted a light bike to ride, both in town and on trips. She wasn’t ready for a bike as heavy as one of the European sport-tourers, and she wanted a (nearly) naked bike, having seen how expensive it is when a faired bike falls over. (Her learner bike fell against the BMW, knocking it over into the lawnmower. No damage to her 535 Virago.)
Wanting her to be comfortable during our Virginia winter, I searched for aftermarket cupholders..er, heated grips for her Suzuki. I found two companies making replacement grips, Custom Heat Inc, http://www.customheat.com/main.shtml and Hot Grips, http://www.hotgrips.com/index.htm. Custom Heat makes very nice grips with easily replaceable foam covers. However these grips are styled to compliment cruisers, not sporty or naked bikes. Hot Grips are more traditional and much closer to the Suzuki original grips. In addition, Hot Grips offers an optional miniature switch and handlebar-mounted housing. In addition, Jim Hollander, Hot Grips owner, will drill the grips for bikes with bar end weights. Finally, both companies include a 2 ohm resistor to give a “low” heat range for the grips. The owners of both companies were very helpful and the products were first rate.
Here is the Hot Grips parts. The large switch isn’t used. Notice the little switch, sealed cover and housing.
Installing the grips is very straightforward. The Suzuki grips are soft rubber and easily cut with a utility knife. Glue on the left bar can be removed with a citrus cleaner. I roughed up the bar a little with a file after cleaning off the old glue. The throttle grip is not glued. It is easily split and removed.
Before the heated grip could be fitted I had to modify the throttle. There are three flanges molded into the throttle. The outer two flanges must be cut off before the new grip will slide on. I cut off the outermost flange with a utility knife and used a mototool with a cut-off disk to remove the first inner flange. I also cut off the two little ears on the innermost flange so the grip would fit tight against the flange. This is obvious when you look at your throttle.
The instructions that came with the heated grips suggest you should remove the ribs on the throttle. Do not do this! I found the throttle grip fit perfectly over the ribs.
Once the old grips are removed and the throttle modified, check the fit of the new grips. I found the throttle fit perfectly with no further work, but had to grind out the end of the left grip before it would slid all the was onto the bar. It is really important to fit the grips before proceeding as the grips are mounted with epoxy. You can’t easily modify the grips once you start to epoxy them to the handlebars. Now mix up the epoxy. Since the grips get hot, chose an epoxy that will not soften when it is heated. Expecting the company would know which epoxy would work well I ordered mine from Hotgrips. I applied a thin, even layer of epoxy to the first three inches of the handlebar and throttle and slipped the new grips on. Adjust the throttle grip so the wire is at about the six o’clock position (straight down). The grips have groves molded on the inside. The epoxy is forced into these grooves and locks the grip to the bar or throttle. By only putting the epoxy on the first three inches very little excess epoxy had to be wiped off the bar. I let the epoxy cure overnight.
The next day I wired the grips and switch. The directions warn you to use a switched + 12 volt source to keep from running the battery down if you forget to turn off the grips. This is very easy on the SV650. There is an unused plug in the headlight housing. The brown wire is ground and the black/white wire is 12 volts when the ignition switch is on. I cut off the plug and soldered a fuseholder to the plus 12 volt black/white wire. I prefer the new spade lug fuses, so chose a holder for this kind of fuse.
I decided to make all connections inside the headlight housing so I ran the pairs of wires from the grips, three wires from the switch and two wires from the resistor into the back of the headlight housing. I attached the resistor to the inside of the left headlight mount with silicon rubber (don’t use epoxy. Apparently the vibration and different expansion rates pop the resistor right off the aluminum bracket. Ask me how I know this!) The wires are tie-wrapped to the existing wires. Make sure you leave a three inch radius loop of wire at the throttle. Hotgrips claims the wire will flex many thousands of times without breaking if you don’t bend it too sharply, thus the loop.
One thing I did find. The switch contacts are not mechanically robust. Do not try and bend the wire once it is soldered to the switch! Jim Hollander was kind enough to send me a second switch. He also soldered a set of wires to it for me. I had the honor to be the first person to break a switch contact! The best way, as explained on the Hot Grips web site, is to strip 1/8” of insulation from each wire. Tin the wires with a little solder and bend the end to give an “L” with about 1/16” on each leg. Fit the wire into the switch contact, adjust so that the wires will fit in the housing and solder with a small iron. Excess wire can be trimmed easily with small side cutters, or better, cut off excess before soldering. If you solder with the switch in the housing be careful, the
housing will melt.
Here is the wiring diagram I used. Remember, I ran all wires, 2 sets from the grips, three from the switch and two from the resistor, into the headlight housing. I used nylon cable ties and the existing wire guides to keep everything neat.
One wire from each grip was soldered to the ground (brown) wire. The other grip wires were soldered to the wire connected to the middle contact of the switch. One side of the switch and a wire from the 2 ohm resistor were soldered to the fuseholder. Finally I soldered the wire from the third switch contact to the second resistor wire.. I used heatshrink tubing from Radio Shack to insulate all connections.
The finished installation looks “factory.” Now my wife’s hands are warm even when the temperature is below freezing. Most of the time she can wear midweight gloves which give her much better control of the bike. She is appropriately grateful. Contrary to the popular saying, it’s warm hands that make for a warm heart!