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1Back to top Go down    OEM heated grips - how many watts/amps? on Wed May 09, 2018 8:32 am

duck

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IIRC it's 36W or 3A for both combined. Is that correct?


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Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

RicK G

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That sounds a bit low. The Oxford grips are 40W IIRC a side so maybe 36 a side would be more like it. Not 100% sure and its dark outside and the drop bears are around so will have to wait to morning to check. Very Happy
The resistance would be around 3 ohms if it's 36 a side, if that helps.


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

Inge K.

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Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

duck

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Look like its 36W per side. (According to that weird Duck guy on ADV Laughing )

I have some old BMW HGs in a box. Maybe I'll pull them out later today and test the resistance.


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Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

Inge K.

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In the notes on the screendump in the link you can see that each handle
draws 1455 mA at 12.7V.


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Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

kioolt

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@Inge K. wrote:In the notes on the screendump in the link you can see that each handle
draws 1455 mA at 12.7V.
That works out to about 18.5 watts. 1.455 amps times 12.7 volts equals 18.4785 watts.


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2004 R1150RT 186,800 miles
1991 K100LT 128,700 miles
1982 R100RT 106,900 miles
Total422,400 BMW miles

AMA,BMWRA,BMWMOA


The cheapest thing on a BMW is the nut that connects the handlebars to the seat.
    

Gaz

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I took the readings in the hand written notes on the factory circuit diagram that Inge has linked to while I was repairing and testing one of the failures I had on the low setting. I have played with a few sets of used OEM heated grips and all of the grips have a resistance around 9 ohms.

I'm a glutton for punishment as I repaired the damaged intermediate harness after the first episode and carefully wrapped with gauze cloth tape thinking that the melting harness would not happen again with better cooling - wrong, same thing occurred next winter. I now have Duck's suggestion of PWM control on 2 of my bikes - works great. Rick G uses them too.

I am helping a friend with the installation of a set of used factory grips on a renovation project and we are using the intermediate harness but have removed the high resistance orange wire and replaced it with one of these 2.5 ohm 25 watt resistors to achieve the low setting. Should work - we'll mount the resistor clear of wiring with some airflow.



Here's a small PWM unit mounted in an OEM blank. It incorporates the on/off switching at the maximum anti-clockwise position like an old style radio volume control (some may be old enough to remember them) and I tightly wrapped it in self amalgamating tape before mounting in the dash pad.




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Gaz
95 K1100LT 0232224; 90 K75 6427509; 87 R80G/S PD 6292136
    

RicK G

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Well 9 ohms makes it look like it is 36W overall (or even less) so the Oxford are probably 40W on full power and at 50% they get too hot even on a -5 morning. That is far more efficient than I had allowed for.


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

duck

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Gaz: A definite yes on mounting those load resistors where they get some airflow and are away from things you don't want to melt as they do generate some heat.

That PWM looks perfectly sized. I just ordered one of those from ebay which is why I started this thread. For what it's worth, the specs on Ebay claim that PWM can handle 90W which should be more than enough capacity for heated grips.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

duck

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Gaz: What's that other LED in the dash? A side stand down warning light?

I have bright flashing LEDs for that in dash blanks in the upper panels on my K1100LTs.

For the K1 I wired in an LED flasher relay so that once you've hit both brakes and the BMU indicator goes out, the BMU indicator will then flash if the the side stand is down.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

Gaz

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Duck, you got it in one.

That dash pad is going on my R80G/S and I am not a fan of the spring return sidestand on those models so have made mine an over-centre type that stays down. I'm old enough that for most of my life I had to remember to put up the stand but just in case I get more forgetful in the advancing years I have put a magnetic reed switch in near the footpeg and as soon as I turn on the ignition that Red LED will start flashing at me if the stand is down.

The graphic I have used below the LED is from a marine set that indicated outboard motor leg control. The graphic I used for the heated grip control is a winch symbol. I've sealed the graphics with clear nail lacquer. The other two holes will have switches for Daylight Running Lights and Driving Lights, both LED types.

Cheers


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Gaz
95 K1100LT 0232224; 90 K75 6427509; 87 R80G/S PD 6292136
    

duck

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My flashing LEDs are pretty bright but have a 15-20 degree viewing angle so when I mount them in the switch blank I epoxy them from behind so that the beam is aimed at the rider's eyes.



__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

RicK G

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What piece of electronic wizardry is that thing below the clock Duck?


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

14Back to top Go down    Re: OEM heated grips - how many watts/amps? on Fri May 11, 2018 12:55 pm

duck

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@RicK G wrote:What piece of electronic wizardry is that thing below the clock Duck?

It's a digital LED voltmeter. Since I have lots of bikes I like to make it easy to check the batteries. It grounds from the turn signal cancel so all I have to do to check the voltage is hit the turn signal cancel. 12V comes from one of the always hot fuses (3 or 4, can't remember which I used) so I don't even need a key to check the voltage.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

RicK G

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Ah Very clever


__________________________________________________
"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

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