Handlebar Warmer problem solved!

[Rockmeister]

I plan to implement Blue Dave's idea. I have a marine grade illuminated (blue, of course) DPDT switch on order that will work very well. My local Radio Shack only had a 10 ohm resistor (1 Watt); will that work? Also, anyone now where the best place to splice into the grip "hot" (Yellow/Red wire) prior to splitting to the right/left grips?

Ran a bunch of tests on the ECU today to determine a dummy load resistance that will not cause an error code.

You need a 15 ohm 20 watt resistor.
Worst case(at 16v), this value of resistor will need to dissipate 17 watts.
Unfortunately, anything above 18 ohms would not always work.

The 10 ohm 1 watt resistor will quickly go up in smoke.
Worst case it will try to dissipate 25.6 watts.
That will last less than a minute. lol

The 15 ohm 20 watt resistor will still get very hot, be careful where you mount it.
Watch that it doesn't touch anything it could burn/melt.
Would suggest mounting it to a frame tube to help dissipate heat.

The mod still has a questionable risk of overloading the magneto causing ignition problems possibly leading to a fire.

Hope this helps!

 

[Blue Dave]

Rockmeister,

Your calculation of wattage with a 15 ohm load @ 16V is right on. I personally would use a higher wattage resistor and / or a heat sink of some sort to be safe. Perhaps two or more resistors wired in parallel to obtain the 15 ohms with the advantage of multiplying the wattage capacity and heat dissipating surface area?

I would not be concerned about overloading the magneto since we are talking about less than two amps of additional "dummy" current draw. The ECU also is safe since it will be providing less current to the "dummy" load than it does when the grips are connected.

Did you test this with the DPDT switch? The reason that I ask is that I am wondering if when you flip the "override" switch with the factory controls on, if the fraction of a second open circuit when the contacts are switching will cause a momentary fault code?

 

[xtcman]

Could a LED be used for the dummy load?
This would give you a indication that are on the bypass system.

 

[Blue Dave]

xtcman,

The LED would not draw enough current to satisfy the ECU load requirement. I had originally thought of an incandescent indicator light for the "dummy" load. The problem is that according to Rockmeister's test you would need at least a 17 watt bulb.

I will however wire an indicator light of some sort into this circuit for a visual indication when the "override" circuit is on. This could be a DPDT switch with the indicator built in or a stand alone indicator bulb wired in parallel with the "dummy" load.

 

[ralger]

This is the switch I will be using. It has on "OFF" which is not needed.

ON-OFF-ON DPDT 20 Amp 12VDC
Sealed Lighted - Blue Lens
Auto/Marine Rocker Switch
Philmore 30-16535

 

[Rockmeister]

Rockmeister,

Your calculation of wattage with a 15 ohm load @ 16V is right on. I personally would use a higher wattage resistor and / or a heat sink of some sort to be safe. Perhaps two or more resistors wired in parallel to obtain the 15 ohms with the advantage of multiplying the wattage capacity and heat dissipating surface area?

I would not be concerned about overloading the magneto since we are talking about less than two amps of additional "dummy" current draw. The ECU also is safe since it will be providing less current to the "dummy" load than it does when the grips are connected.

Did you test this with the DPDT switch? The reason that I ask is that I am wondering if when you flip the "override" switch with the factory controls on, if the fraction of a second open circuit when the contacts are switching will cause a momentary fault code?

I agree with the multiple resistors, was just providing the total resistance needed.
Can't go much over 15 ohms, 18 ohms would NOT always work.
If you go down much, you waste more power.
No point in wasting power you don't have! lol

The ECU is safe here, it isn't nearly as fragile as people think, just be careful with your wiring.

The aluminum case resistors with heat sinks usually fail when they get hot by pushing the insides out of the ends.
A very short spike will make them fail. (But they look cool! lol)

Didn't test with a switch. Was focusing on the load required.
Do know if the warmers are "off" it won't fault when dis-connected.

Overloading the magneto is a distinct possibility.
You only have about 40 watts of power left to run accessories.
The dummy load can draw a bit more than 15 watts, that's almost 40% of your available power.
I believe most electric shields are 24 watts or so.
Doesn't leave much...

The fuel injected sleds are especially sensitive to the power available, (They use more electrical power also).
If it isn't right, the injectors won't be right, same with the ignition.

I like the idea, it is functional, just don't like that it isn't foolproof and may cause a fire.

Hope this helps!

 

[Blue Dave]

Ralger,

The center off position will most likely cause a longer momentary open circuit when switching circuits. I am not sure how long the circuit can be open with the factory controls on without causing a fault code.

Of course you could turn off the factory controls before switching on the "override" circuit but if you plan on doing that everytime then you do not need the DPDT switch and dummy load anyway.

Like I said earlier, I want to be able to flip the "override" switch at any time regardless of where the factory controls are set and not trigger a fault code.

Rockmeister,

I still do not think that overloading the magneto is a valid concern because nobody is going to leave the "overload" switch on for a long time and the battery can supply short term extra "capacity" if needed. However I stll feel that even without a storage battery we are not taking more out of the electrical system than it can safely supply.

 

[ralger]

Blue Dave:

I guess I would rather have a fault code that can be reset vs. any risk of fire/damage or anything else that has been mentioned. I am looking for a simple solution; it just keeps getting more complicated all of the time.

I will be using the DPDT only to make the wireing easier since I plan to splice into the Y/R (hot) wire after the plug for each grip, which is very accessable. This will also make it very easy to go back to factory wiring. Once you have had a chance to go through the wiring, you might agree.

I will post a schematic and pics once I have implemented and tested.

Thanks

 

[RacerDave]

Anything new to report from the handgrip police?

 

[mr rxl]

Working perfect. I converted my friends 07 Attak ER and to solve the error code issue all we did was turned the warmers off and unplugged the switch. Now there is no chance of accidently turning them on and having the check engine light come on.
On my 08 GT, I just set the warmers to off and left it on shock mode. No problems.
I went through the trouble of putting a hi/low switch in, but I think just on or off would be fine. When they are on high, they are not burning your hands, just a constant heat.
If you find that your hands are too hot, just switch them off.

 

[olsmann]

So do we have a plug and play kit for the average guy yet or what?

 

[Rockmeister]

So do we have a plug and play kit for the average guy yet or what?

Probably about 2 weeks!
Will be much more than simply a switch though.

 

[xtcman]

I rode over the weekend, but first I fill my bars with spray foam.
It seems to heat up faster and hold the heat. I never ran over half heat. I may take 1 more ride before I get into wiring.

 

[boat.man]

I fixed my drawing and added a relay.
Tie right into the battery and have a fast warm up.

OK i am no EE but could you throw a diode in-line between the ecu and grip, then add switched power between the grip and diode to supplement the current to the grip? The diode would stop any feed back to the ecu.You could run both when needed and just shut off the toggle switch when your hands are to hot,,, if that is possible!

 

[Blue Dave]

I had also thought about using a diode like boat man describes above, however I had a few concerns. Specifically:

1) How the pulses from the ECU and the straight 12dc would interact.

2) Finding a diode with enough current capacity.

3) What would happen to the ECU if the diode failed and voltage could feed back into the ECU.

This is why I like the DPDT switch with dummy load. There is no chance of damaging the ECU, no fault codes, and you can switch on the "override" circuit without first having to shut off the factory controls.

However I am still very interested in seeing what Rockmeister has come up with!