K11 Owners Group

[Flying Duck]

My farkin' LT tried to self-immolate today. GRRRRRRR!
Went for a 70 mile ride to meet someone, pull into the parking lot and there's GOBS of magic smoke pouring otu form under the tank.

Anybody wanna hazard a guess as to the cause?

(I know the answer, I"m not looking for technical advice.)
_________________
93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[Klinker]

Rodent's nest next to some hot parts?
_________________
tlp
1994 K1100RS

Only the Reasonists. They believe in an evidence-based world, something called Rationalism. But it's a tiny group, not so influential.
- Page Griffin

[Flying Duck]

[rydor]

A short in the fuel gauge sending unit wiring resulting in burning insulation under the fuel tank?

[Flying Duck]

[Off the grid]

Fuel hose popped off?
_________________
Bane of your existence since July 2006
2007 Triumph Tiger ABS. "Sabertooth"
2009 Husqvarna TE610. "The dirty Italian mistress"

[Flying Duck]

[Off the grid]

Silver bullet vibrator?
_________________
Bane of your existence since July 2006
2007 Triumph Tiger ABS. "Sabertooth"
2009 Husqvarna TE610. "The dirty Italian mistress"

[Flying Duck]

OK, I'll give. In their infinite lack of wisdom, the highly-esteemed German engineers at BMW didn't think it was necessary to put a fuse in the heated grip circuit.

This has been known to burn other K bikes to the ground. (Imagine watching your fuel tank go off. ) You'd think they would've fixed it by the time the K1100s came out, huh?

I was lucky. It destroyed the intermediate HG wiring harness and was starting to melt surrounding wires' insulation but I got the bike turned off just in time to prevent further shorting and mayhem.

MORAL OF THE STORY: If your heatred grips stop working, it's a good idea to stop and take a peak under the left side of the tank.

And my LT only has 30k on it too.

The guy I was meeting was very impressed at how quicly I got the seat and tank removed. I was pretty motivated though having heard other stories of this occurring.

I have an extra slot in my aux fuse blockon the LT so I'll be adding a fuse to the circuit when I fix this up. After today, I'm going to rewire the HGs on my K1100RS too in the near future. I do not want to experience this again.
_________________
93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[Off the grid]

I was actually going to say the heated grip wiring but I thought they were more in the center cluster.

I know because mine burnt to a crisp too.
_________________
Bane of your existence since July 2006
2007 Triumph Tiger ABS. "Sabertooth"
2009 Husqvarna TE610. "The dirty Italian mistress"

[Lone Rider of Santa Fe]

Diito. Happened while on the road in Nelson, BC. Caught it before the smoke got out but nevertheless fried several wires in the harness. Created somewhat of a comotion with the locals while tearing down the machine in order to troubleshoot the problem what with parts spread out along the sidewalk
_________________
Paul
'96 K11RS "Victor"

[Flying Duck]

Update: I was wrong.

The heated grips ARE fused through fuse #1.

What causes this problem is that when you use the low setting, the current runs through a resistive wire. This lowers the voltage to the HGs and thus produces less heat. BUT those extra volts are heating up the resistive wire sitting under your tank. If you have your HGs on the low setting for an extended period of time.....

I suspect the reason the fuse doesn't blow is that with the resistive wire in the circuit, once it's shorted, it doesn't pull enough current to blow the 15A fuse like a "real" short would.

But it's still a sucky design if it turns a $15,000 motorcycle into a marshmallow. IMO, BMW should've done something about this when they did the major redesign for the 4 valve Ks. (or even issued a recall on the 2 valves.) Something that can cause your bike to burn up seems rather dangerous to me.

REVISED MORAL OF THE STORY: Don't use the low setting on your HGs.
_________________
93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[jarnbak]

The wiring for the heated gribs?

Palle.
(with a k11lt with burned out wiring for grib heating)

[rkildu]

When I put heated grips on my airhead, this was a snowmobile system, the unit came with a ceramic ballast resister. The instructions said to mount this where it could be cooled by some airflow.

It sounds like some electrical guru, I definately do not qualify, could spec out a resister and design a modification to fix this issue. I know I would be very interested in it.

I will look through my maintenance logs and see if I can find the specs on that resister and pass it along.

This is about the third time I have heard of our K's catching fire! I wonder if all had a similar problem?

Duck, can you describe exactly what and where to look for this resister wire so we can do an inspection?


Thanks
Rod

[Flying Duck]

The resistor part is easy. You could also use a 6ohm 50W load resistor like this:
http://www.streetbeatcustoms.com/jam650le.html

I may wire one of those in when I fix my HGs but I may just replace the intermediate HG harness and never use the low setting.

That one's a bit expensive. They're about $5 at an electronics supply store but that's the first one that came up on Google. They do get hot though (that extra power has to go somewhere) so it's important to mount it where it can dissipate heat without burning anything as you noted.

The heated grip wiring connector is under the left rear corner of the tank. There's small black two-lead connector with VERY short leads coming out of the main wiring harness along the left frame rail. It has green (or maybe it's green with a black stripe) and brwon wires coming into it.

The intermediate wiring harness that plugs into it that and branches off to a square white connector that goes to your heated grips and the other branch goes to a flat white three wire connector that goes to the HG switch. The wiring that goes to the HG switch has black, green and orange wiring.

It's the taped up clumpy thing in the middle of the intermediate wiring harness which holds the resistive components.

Here's a post-flambeau pic I took yesterday which will help you locate the HG wiring:



The easiest way to prevent this from happening without even removing your tank is to disable the low setting. Pop the heated grip switch out of the dash and snip the orange wire coming out of the top of it. (Snip it right where it's soldered to the back of the switch.) Voila! No more burning bikes.
_________________
93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[Shoganai]

Wow, I've been following this thread with intrest.

Tell me, how is it different between the high and low settings as it relates to risk of producing a fire?

Would replacing the HG wiring harness with new solve / prevent this issue?

Do you have a pic of the damaged area?
_________________
1993 K1100RS aka The Shop Whore
1994 K1100RS aka Blue Streak

The long road is a rainbow and the pot of gold lies there.
So slip the chain and I'm off again,
You'll find me everywhere. I'm a Rover. - JT


Nana korobi ya oki

[Flying Duck]

This happened only VERY occasionally on K75s and K100s but it doesn't seem to be near as bad as the frequency on the K11s. Perhaps there was "bad batch" that made it into some K11s. I don't know. Will dropping $40 on a new one at the dealer make a difference? Well, at least it will be newer so I imagine less prone to this sort of faiulre. Perahps it's been upgraded. The ETK doesn't show a parts supercession though so who knows?

On high, the power to the HGs is the normal bike voltage with no resistive circuitry and the current travels through normal wire. On low, the power is routed through the resistive circuitry - which is the stuff that burns up. This cuts the voltage at the grips to reduce the heat level there. So that's why I don't think this is an issue if you avoid use of the low setting since the resistive circuitry isn'y in play. Also, I suspect the resistive circuitry, when it shorts, does not blow the fuse because it's not a "real" short since there's still some resistance in the circuit.

The 2 valves had a 7.5 volt fuse in #1 so maybe that helped avoid this by blowing before things get nasty. On the four valves they went to all 15A fuses. Perhaps this was overlooked? I'll bet trying a 7.5A or 10A fuse might reduce the chances of this happening without blowing a fuse.

Not sure what I"m going to do, May just rewire it so high iis the only mode, might replace the intermediate harness, may replace the foactory low ciccuit with a 6 ohm load resistor is a "safe" place.

The damage was in that pic. the resistive circuitry has all of it's inculation metled off, behind the word "Power" in my diagram is a very melted Posi-Lock connector for my driving lights. Didn't look under the tank at the insulation but I doubt there's anything other than a char mark.
_________________
93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[max]

Duck:

Simple fix for this would be to not use a resistor at all, but use a delay relay to pulse the elements on/off with a varying duty cycle - 100% on = high, 1/2 on 1/2 off = low, etc etc... you'd just need to find something like an add-on windwcreen wiper variable delay kit and fix it to see 12v on its enable line when the switch is in LOW (and make the adjustment potentiometer a preset trimmer, and make sure the relay can take the element current, or get it to drive a bigger relay).

HTH (and I don't get Jim replying for me again)

Max

[Jim]

[max]