Infrared Thermometer Owners with Heated Grips Needed

[deeve]

Hello, I've been over at the advrider forum for a while, but I keep reading about good posts/info over at UKGSer, so here I am. I'm trying to figure out why the heated grips in my 09 GS Adventure are so much colder then in my 09 RT. On high, my RT will become too hot to hold after about 15 mins. On my GS it seems that the barely get warm on high. I checked both with an infrared thermometer in my garage under the same conditions and got a temp of about 64C on high with the RT. The GS could only reach 49C on high. On low the RT was 38C and the GS was 24C. Both grips on both bikes were the same temp so I think they were working properly.

I've read some on the heat issue here and there were some posts about older GS's having different bars that retained the heat better. It seems to me that the RT has thicker grips and thicker bars so I would think they would inhibit the hear more.

I posted a similar question over at advrider and got some numbers, but I was looking for more if I could. The BMW tech I spoke to thought maybe the temp could be turned up or altered somehow via the ZFE...

Thanks!

DAVE

 

[Deleted account 190920001]

does the RT have steel bars? if so thats where the difference is. Alloy is a far better heat conductor than steel. That said I have an 09 GSA and the grips are fine, certainly hot enough to give me sweaty palms when on full.

 

[deeve]

I think the RT has a steel tube. The GS Adventure is aluminum isn't? Would aluminum conduct the heat away quicker then so they do not get so hot?

DAVE

 

[Deleted account 190920001]

yes Aluminium conducts the heat away much more rapidly hence cooler grips.

 

[Mr K]

We use aluminium ladders at work, they suck heat from your fingers like a heat sucky vampire kind of thing.

Sorry, not scientific, but......

 

[deeve]

Hmmm...thanks guys. It seems like that is probably the problem. I just read up on aluminum bars and grip heaters. It looks like a lot of the aftermarket folks recommend not installing them on aluminum bars.

On another note, I think in 2005 BMW had thin walled steel bars, but then in 2006 they switched to aluminum. So, I guess if I really want to get to the bottom of it I could buy/borrow/steal some steel bars and give it a shot.

 

[Kremmen]

That's why automotive radiators & the heat exchanger in my boiler at home are made from it ....and bloody shite it is too ...bring back cast iron, good enough for IKB good enough for me..

 

[Deleted account 190920001]

not sure but I don't think the early bars were the same diameter at the clamps so might not fit the newer top yoke.

 

[deeve]

The other idea would be to figure out a way to better insulate the bar from the heated grip.....

 

[Kremmen]

The other idea would be to figure out a way to better insulate the bar from the heated grip.....

So why not just poke something like pipe insulation lagging up the inside of the bars.. any heat which travels inwards, should be reflected back

 

[TeaPig]

So why not just poke something like pipe insulation lagging up the inside of the bars.. any heat which travels inwards, should be reflected back

A lot of the heat will also bugger off down the length of the bar, though some insulation may help prevent a small amount of heat loss to the air inside the tube. On 1150's, are not the grips seperate sections of tube on rubber isolators? That would help, as it would if the factory decreased the resistance of the heating elements so the grips simply emit more heat.

 

[deeve]

I took the clutch side bark buster/bar weight off. The grip is a plastic tube over the bar then the heating element followed by the rubber grip. The bar end weight is steel and goes inside the bar about half the length of the grip. The bolt that holds on weight threads into a steel insert that appears to go probably in far enough to be under the rest of the grip. It would be pretty hard to fill the bar with anything that would insulate it with any significant amount since most, if not all, of the space under the grip and inside the bar if filled with steel parts.

There may be enough room to slip in a plastic insulator between the tube and the bar, but that probably would only work on the clutch side with not enough clearance on the throttle side to guarantee smooth operation.

It would be nice if through the ZFE the heat could be cranked up somehow, but I bet even if there is BMW would not want to spend any time working on it. If I could get some hard numbers showing that mine are not as hot as similar GS's then I might have something, but I think mine are probably "normal" Would there be way to compare the heating elements themselves to see if there is a difference between the RT and the GS? I have both in my garage, so really I would only have to pull one apart...I just don't know what to measure.

DAVE

 

[wessie]

Have you checked the handlebar switch on the ADV? If it is faulty then your grips might stay on the lower power setting.

If the switch checks out then invest in a pair of muffs. Together with the 49C grips they will keep your hands toasty.

 

[deeve]

I did check the switch by measuring the temp with them on low and on high. I did get two distinct temps that were equal between the two. Last night I did go out on below 0 degree temps with the hippo hands from my RT and it did help quite a bit. I just miss the "shit this is hot!" feeling that I get from the RT.

 

[jeff]

So why not just poke something like pipe insulation lagging up the inside of the bars.. any heat which travels inwards, should be reflected back

Have virtually no effect. The whole purpose of insulation is to trap still air which short of a vacuum is just about the best insulator there is. The bars ore full of trapped still air.

I would suggest that the cause is the alloy bars, extremely good conductors of heat and thus very good at cooling the grips.

I have the same difference in heating performance with my GSA as against earlier BMs with steel bars. Grip puppies compound the problem.

I

 

[chad]

So why not just poke something like pipe insulation lagging up the inside of the bars.. any heat which travels inwards, should be reflected back

a good way is to fit some heat shrink to the bars . it just adds that extra layer,i would think this problem mostly lies with the left hand grip as the right is seperated from the bars by the throttle tube

so it may not just be down to the ali bars if the temp is the same on both grips.

 

[peter-k]

The BMW grips are expensive and not that good. Nobody asked for it, but for those who are considering about heated grips, the ones from Oxford are apparently the best in the market. clicky

 

[Toad]

The grips on my 05 1200 GS were hotter than the grips on my 08 1200 GSA??

 

[peter-k]

... snip
On another note, I think in 2005 BMW had thin walled steel bars, but then in 2006 they switched to aluminum. So, I guess if I really want to get to the bottom of it I could buy/borrow/steal some steel bars and give it a shot.

The 12er ADV had alu from the beginning. For the standard GS they are alu from model '08.The steel bars before were surprising heavy (to me at least).

 

[TeaPig]

It would be nice if through the ZFE the heat could be cranked up

Would there be way to compare the heating elements themselves to see if there is a difference between the RT and the GS?

DAVE

You could compare them by disconnecting the grips from the loom and then use a multimeter set to the ohms scale to measure the resistance . The lower the resistance the more current the heating element draws and hence the hotter it becomes.

traditional heated grips use a switch to connect the pair of grips in series (higher overall resistance) to make them warm or run them in parallel (lower overal resistance) to make them hot. Without a diagram to look at I've no idea how it's done on the GS as it may be that the switch simply informs the computer which setting is selected and the ZFE unit then either supplies a constant current or regulated voltage to limit the power (and hence heat) available at the grip. It would seem a over-complicated way to do it but that's nothing new.

As I've said in previous posts, using gloves with limited insulation in the palms allows more of the available heat to get to your hands. Skiing gloves work well as long as you don't intend to fall off much.