R1100RT Heated Grip Circuits

[Danny caddyshack Noonan]

I'm adding aftermarket grip heaters but will use the factory switch.

 

Is there already a resistor in the harness, or switch, for the heated grips? My kit came with one on a small harness and I'd like to guesstimate what I'm going to do when all the other parts arrive.

 

thanks in advance

[T__]

74c5, yes there is already a resistor wire in the factory harness,, how well it will work with your new heated grips depends on how the new grip resistance matches up to the factory grip resistance..

 

Twisty

 

[Danny caddyshack Noonan]

Good point. 7.2 Ohms is what the new ones read.

Is there a benchmark for factory? Edit: Or the value of the resistor in the harness circuit?

[T__]

74c5, it’s been a few years since I measured the in-harness resistor wire & I don’t have my shop notes handy here but if I remember correctly that resistor wire is somewhere’s just under 2 ohms at room temperature.. Not sure that will do you much good though unless you know the working resistance of the aftermarket resistor(s)..

 

Twisty

 

[Peter Parts]

Using resistors to control resistance heating on a bike is plain daft.

 

But then I'd say the same thing about the concept of grip heaters - allowing for their convenience and the fact that the bike manufacturer can stick 'em on your bike but can't just supply you with plug-in gloves.

 

Make your own grip heaters by wrapping 31 gauge wire. Piece of cake. Like 70 feet - my memory could be way off.

 

I fooled with winding my own and worked just fine - a winding over the stock grips and below my winter-time bicycle handlebar tape layer.

 

But I find Gerbing gloves make a whole lot more sense for serious cold winter riding and using the right Thinsulate gloves works fine for cool days.

[AndyS]

Using resistors to control resistance heating on a bike is plain daft.

 

But then I'd say the same thing about the concept of grip heaters - allowing for their convenience and the fact that the bike manufacturer can stick 'em on your bike but can't just supply you with plug-in gloves.

 

Hi Pete

Do you deliberately come in with outrageous statements just to see if you can get forums to bite?

Resistors on resistance heaters have been used successfully for years and are a simple and inexpensive way for controlling output of heaters. Certainly there are much 'better' ways, but these all work out more expensive than simple power resistors. Thousands of riders are pretty impressed with the addition of heated grips (whether OEM or aftermarket units). The enable the rider at the flick of a switch - to carry on riding in comfortable summer gloves way into autumn, and winter gloves long before the need to switch to heated gloves.

As for fabricating your own heated grips, well of course it can be done...just like many out there could machine many of their m/cycle components, but unless you really have a desire to reinvent the wheel; someone else has done the work for you. (Much like the oil cooler fan project - which I am not criticising only making an observation :-}...jolly good but for the time required and costs of parts, the RT-P system would have given satisfactory results).

Andy

 

[r77toy]

Where is the resitor in the factory harness?

[Peter Parts]

Using resistors to control resistance heating on a bike is plain daft.

 

But then I'd say the same thing about the concept of grip heaters - allowing for their convenience and the fact that the bike manufacturer can stick 'em on your bike but can't just supply you with plug-in gloves.

 

Hi Pete

Do you deliberately come in with outrageous statements just to see if you can get forums to bite?

Resistors on resistance heaters have been used successfully for years and are a simple and inexpensive way for controlling output of heaters. Certainly there are much 'better' ways, but these all work out more expensive than simple power resistors. Thousands of riders are pretty impressed with the addition of heated grips (whether OEM or aftermarket units). The enable the rider at the flick of a switch - to carry on riding in comfortable summer gloves way into autumn, and winter gloves long before the need to switch to heated gloves.

As for fabricating your own heated grips, well of course it can be done...just like many out there could machine many of their m/cycle components, but unless you really have a desire to reinvent the wheel; someone else has done the work for you. (Much like the oil cooler fan project - which I am not criticising only making an observation :-}...jolly good but for the time required and costs of parts, the RT-P system would have given satisfactory results).

Andy

 

Hi Andy -

 

I try at no time to say anything I don't believe or wouldn't want to see quoted on the front page of a newspaper. While I like a bit of joking I try never to say anything sarcastic (in the sense of uttering the opposite of what I actually mean thinking everybody will get the big joke).

 

It is patently ridiculous to control heat by making heat somewhere else, and esp. on a bike for several compelling reasons.

 

If you would take a moment to eyeball after-market strip heaters, you would notice the intelligently designed ones have two circuits with shared paths and NO resistor is needed. Might take 30 seconds of thought to calculate the right series/parallel values needed. Duh.

 

Now that is the proper way and it is essentially free to make a two-level strip heater or for BMW to make theirs that way too. Never thought of doing it that way? I hope you can find some time to brush up on Ohm's Law.

 

As for my second thought you ridicule, it is likewise daft to put heat under your grip rubbers in order to heat the "handlebar" and secondarily, your palms (only your palms... which is the part of your hand that needs it least). Granted, as I said before, it is convenient, etc.

 

BTW, when a person takes time to design, make, and typically re-design some mod, they aren't wasting time - they are creating quality time.

 

Footnote for home builder: swellest way today to control Gerbing stuff or grip heaters is to build a continuously variable DC controller. Google "MX 033", it will handle 15A.

[T__]

Peter, actually the system that BMW, Harley Honda, Guzzy, etc uses is a very good system.. Simple (very simple) ,, easy to assemble,, only (1) power & (1) ground wire running to each grip,, no extra mounting of PWM’s or other power factor devices,, cheap,, allows simple wire routing.. Seems just about as reliable as a paper clip..

 

Doing anything different adds either cost,, and/or complexity,, and/or extra wiring,, and/ or added assembly costs.. It would definitely add complexity..

 

BMW runs the resistor wire inside the wire harness (I believe Harley does also) so the packaging & assembly is very easy & trouble free..

 

It would be nice if the heated grips could be run is series for low & parallel for high but that takes extra wiring,, adds to much resistance to get a decent heating on low,, & doesn’t gain much..

 

Obviously using a PWM set-up would be nice as that would allow variable temperature control but that adds cost,, complicates switching & mounting,, & requires a more complex switch or control assembly..

 

The bike manufactures can’t really offer heated gloves as replacements for heated grips as that would take either running wires up the sleeves or inside clothing or require keeping the hands on or very close to the hand grips ALL the time (people do run the wires inside their clothing but that isn’t really a viable option for mass consumer usage)..

 

Heated gloves do work very good but most lack palm heating & heated grips fill that void by heating the hands in the palm area..

 

I guess if I were a vehicle manufacturer & I had a long time proven simple system for heated grip control I wouldn’t want to change either..

 

 

BMW has progressed a little on the 1200 hex as they do use a pulsed type heated seat control for the large heated front seat (I’m not sure if the passenger seat does or not as I have never measured the voltage to that on low).. I’m not sure if BMW modulates the front seat for better more even seat heating control or more to save a little power as it would take a rather large resistor to drop the seat current due to the seat’s heating element size..

 

Twisty

 

[Peter Parts]

Peter, actually the system that BMW, Harley Honda, Guzzy, etc uses is a very good system.. Simple (very simple) ,, easy to assemble,, only (1) power & (1) ground wire running to each grip,, no extra mounting of PWM’s or other power factor devices,, cheap,, allows simple wire routing.. Seems just about as reliable as a paper clip..

 

Doing anything different adds either cost,, and/or complexity,, and/or extra wiring,, and/ or added assembly costs.. It would definitely add complexity..

 

snip

Twisty

 

Can you explain how BMW does it without using the same DPST switch and three wires somewhere along the way? I'm having really big trouble seeing the resistor control with the extra hot pieces and connectors as simpler than the properly designed series/parallel way the way the after-market film heaters do it.

 

GM also sticks with things because it doesn't require retraining the maintainers. Well, they used to.

[T__]

 

Peter, it just doesn’t get any simpler than this.. Only one power wire & one Ground wire to each grip heater & only 3 wires to the switch..

 

 

Twisty

[NonComp]

Twisty, my ST13 has a four position controller. Is that a similar setup to the Hi/Low scheme?

[Peter Parts]

Peter, it just doesn’t get any simpler than this.. Only one power wire & one Ground wire to each grip heater & only 3 wires to the switch..

Twisty

 

Twisty, as I am sure you know without my help, the after-market wiring is nearly the same... except there's no hot resistor needed. Sounds simpler to me, eh.

 

So I really think this argument about which is simpler is a red herring.

 

Also, there's no hot resistor cooking 5 watts or so tucked away someplace - not the sort of thing a critical eye would accept.

[T__]

Twisty, my ST13 has a four position controller. Is that a similar setup to the Hi/Low scheme?

 

 

Glen, I’m not sure what the newer ST13’s use.. It could be as simple as just adding an additional contact or two in the switch then adding a couple of extra resistor wires in parallel (or actual resistors )..

 

I don’t think they have gone to PWM (pulse width modulated) yet but I suppose it is possible as that is the future of power control.. It might be shown in your service manual..

 

Twisty

 

[Danny caddyshack Noonan]

Thanks Twisty,

My kit came with a 2 Ohm, 10W resistor. I'm going to assume it'll work and when I tear down, will short the circuit and measure the harness then at the four pin connector. It can't be too far off and, as long as I use the whole harness and switch shouldn't overload anything. It's all about testing in the garage and throwing the current meter on it. I can always go with the aftermarket wiring instead later.

 

Peter,

On the other subject of gloves vs grips for what is better? There is no answer, only opinions. If the rider wants both, like me, cool.

 

Maybe someone will come up with a "perfect" solution like using the engine oil or uranium pellets to heat the grips? That should solve the nasty problem of Ohms Law.

[Peter Parts]

snip

 

Peter,

On the other subject of gloves vs grips for what is better? There is no answer, only opinions. If the rider wants both, like me, cool.

 

Maybe someone will come up with a "perfect" solution like using the engine oil or uranium pellets to heat the grips? That should solve the nasty problem of Ohms Law.

 

You've brought together several thoughts and done so graciously.

 

The essential issue is that there are lots of valid "opinions" or matters of personal taste when the challenge is easy (say, mild cold and superslab riding). But in fact there are no adequate tech-fix solutions when the challenge is hard (say, very cold, sporty riding, and you don't want to look too weird).

 

Don't forget:

 

"Hippo Hands"

Vaseline on your face

slow-burn carbon packs in your gloves and boots

GS hand protectors

three-finger "lobster" gloves

thinking warm thoughts about your destination

 

One February, I went camping out of doors in a tent on Resolute Bay. OK, it wasn't for fun: the Canadian Coast Guard needed some data on shipwreck survival.

[Danny caddyshack Noonan]

You forgot Capsicum powder in the socks.

 

If you get any on your hands, just don't forget to wash your hands before taking a leak.....

[460Jetboat]

Or playing with your S.O.'s leaking equipment.

.......don't ask