09 handwarmer resistance

[yamy07]

Yes that's basically what I plan on doing, the resistor that is. Looking at Gades Fluke Scope it appeard that at full power the pulse is basically half on half off. I can't see the time scale but it really doesn't matter, it only on 50% of the time. I really think this is the main issue. According to the Hot Grips site the PWM allows 0-99.5%. Which I read as 0% or off to darn near continuously on. At 99.5% the switch in one minute would have a total off time of only 0.3 seconds. The way the stock appers to opperate it would be off for a total of 30 seconds during a minute. Little bit of a difference.

Someone needs to figure out how to re-flash the Yamy ECU so it gives a longer pulsewidth on high. But, seriously- I wonder why Yamaha limits the on time pulse to 1/2. Would it be the stator is putting out AC & we're seeing the 1/2 rectified DC? It's been a long time since my electronics classes.

 

[BLUEBALLER]

I have the SAME hotgrips on another sled and they get SMOKING hot at that wattage. I just don't get what part you guys can't wrap your head around??

You are not comparing apples to apples unless your previous example had the same amount (%) of resistance added. You will see less then half of the power you are assuming. I think you are forgetting that the resistor added in series creates a voltage drop, which will reduce the voltage on the hand warmer. The handwarmer will see less then half of the voltage and that is why your power is reduced. You are correct, you did add them to reduce the current flow, but you also reduced the voltage.... which reduced the power even more..

My other sled's hotgrips are wired in series.

Here is my math, I had to change the resistor values because the resistance I measured on my new hotgrips are actually 3.5 ohms each.
If you don't agree with me, then I can't help it.

I'm assuming 14 volts as a source. I'm sure I read that in the manual.
It is a series-parallel circuit. I'm going to now use a one ohm resistor in series with a 3.5 ohm hotgrip. Both of these are in parallel with each other with the 14 volt source.

so....... here we go.
resistance of leg 1 = 1 ohm + 3.5 ohms = 4.5 ohms total
resistance of leg 2 = 1 ohm + 3.5 ohms = 4.5 ohms total

Total resistance = 4.5 ohms x 4.5 ohms divided by 9 ohms = 20.25/9= 2.25 ohms

total power = 14 x 14 divided by 2.25 ohms = 196/2.25 = 87 watts total

power in each leg will be 43 watts

current through each leg will be 43/14 = 3.1 amps

power through each hotgrip will be 3.1 x 3.1 x 3.5 = 33.6 watts each grip

total current through ECU will be 6.2 amps.

Ruffyrider, I had to recheck my math as you pointed out, I wasn't taking into account the resistor that I added. thank you for pointing this out.

are we on the same page now? does everybody agree?

I hope so. NOW, let me enjoy Hay Days damnit Only 3 more sleeps

 

[Timeline]

This is what I have been saying I'd like to try. I think Blueballer has got the Hot Grips but I don't know if he has got the PWM controller to check the frequency of the pulses. In an earlier post someone contacted Hot Grips, I was hoping that they would chime in with some specs.
I'd like to keep the stock bars with the heated hooks.
The code could be easily fixed by installing the correct resistor of the same value as the resistance of the grips. Basically the wires that are disconnected from the grips that go to the ECM.

Yes that's basically what I plan on doing, the resistor that is. Looking at Gades Fluke Scope it appeard that at full power the pulse is basically half on half off. I can't see the time scale but it really doesn't matter, it only on 50% of the time. I really think this is the main issue. According to the Hot Grips site the PWM allows 0-99.5%. Which I read as 0% or off to darn near continuously on. At 99.5% the switch in one minute would have a total off time of only 0.3 seconds. The way the stock appers to opperate it would be off for a total of 30 seconds during a minute. Little bit of a difference.

Where is my sled so I can start doing some testing!!!

Well I did a little testing myself tonight and this is what I found.

First picture- 7.0ohms per grip.

Second picture- For those that asked earlier, this is where the 7 ohm resistor would go. The plug beside it with the numbers on it attach to it and come from the grips. This would fool your ECM to think there are grips there, therefore no code.

Third picture- This confirms that my grips are wired in parallel. Yours may be different.

Fourth picture- This is where I got a slightly different reading than Glade-Thrasher. I was able to read different voltages at different settings. Notice the bars on the display. High heat 8.82 volts.

Fifth picture- Low heat 3.790 volts.

What I didn't measure was the voltage that the reg\rec puts out. (had to shut her down as I heard the fan come on ) If the Hot Grips controller can give us 99.5 % of between 12.6 and 14 volts which the magneto puts out we could be onto something here.
I also measured the frequency and found it to be 60hz which means that the duty cycle that Glade-thrasher was reading is pulsed at 60 times a second.
I think I'll be trying the controller from Hot Grips with my own heaters.

 

[Timeline]

Blueballer your calculations are correct. These are readings I took earlier and put in another post.

Take a deep breath and relax dude. We're all in this together. There are a lot of intelligent people who have replied here. We'll get this thing figured out. In fact here, have one on me.

 

[arteeex]

Here's what little I think I know about this; a meter that reads (calculates) voltage as an RMS value is going to register a pulsed signal as a lower voltage. The root-mean square function is an averaging mechanism that would treat the larger time gaps between pulses as a larger number of lower values in the calculations. For example, imagine that the meter calculates simple average (not RMS) of ten points read each second for 10-seconds. If seven of these points are at 0V and 3 are 10V the meter will display 3V as the average voltage for this recording period. A scope or meter as was demonstrated earlier is needed to see that the peak voltage is probably still about ~12VDC during the on-cycle.

However, this doesn't really affect the view from the street. The power (work / time) output is essentially the same for this discussion. Three volts over 60-seconds will deliver the same power as 6V at a 50% duty cycle (equal time on and off) in the same period. So, the point can still be made that there isn't a great deal of output from the grip. Shortening the off-period is probably the key to hand warmer happiness.

I really appreciate all the thought going into this thread. I’ve got a dollar for the first one to crack this nut. I’d love to get the little hand warmers out of my gloves this winter.

Maybe Mr. Hot Grips can provide a plug-in solution,

 

[Turtle]

OK - I think I finally caught on to what you guys are doing.

You're going to take the '06 style grips and wire them in parallel (as many have done). But this makes them so super hot that you can't use the full sweep of the grip settings. So you are going to add a resistor in series of the grips to bring it back down a tad.

Right? ...

 

[Vector1]

I just talked with the owner at HotGrips and he said there is nothing they can do to help us. They don't have a grip that will go over the bars with the hook. He also does not thing their controller would help. So I called RSI Performance, who has a hi power grip heater element. I think they are doing some testing on the Yamahas for a fix. I asked that they join the site and offer some help.

 

[LJ 452]

Well, at any rate I orderd the PWM controller yesterday and I will find out. I've got acess to a Fluke Scope simular to the one Gade used. I really think we can get this figured out. Personally I don't think that Hot Grips realizes what we are talking about as Yamaha has completely changed there grip heating system three times in the past 4 years. Plus they are not going to tell you to do anything except wire their grips as the directions tell you. If the controller permits more "on" time I see no reason the grips would not get hotter. From what I can tell, all grips are between 7 and 11 ohms. If someone on here has access to Cat/Poo/Doo grips and can measure the resistance I think you'll find the same or close to it. So what's the difference...the control. I should have my control within a few days and hopefully I will be able to do some Scooby Dooing, I have my wifes Phazer so if need be I can do some testing on that. As said I think between all of s on here we can come up with a few different options. This stuff is simple but complicated as there are some unknowns that we are still trying to determine. It's only Sept, so we do have some time.

Right now we have two concepts going, one would maintain your stock controller the other will eliminate it. Lets keep both options going as some may prefer one over the other.

Lets keep the constructive post going.

 

[ruffryder]

The power (work / time) output is essentially the same for this discussion. Three volts over 60-seconds will deliver the same power as 6V at a 50% duty cycle (equal time on and off) in the same period. So, the point can still be made that there isn't a great deal of output from the grip. Shortening the off-period is probably the key to hand warmer happiness.,

Excellent post! This adds another layer of complexity to the situation, especially when comparing power of handwarmers between sleds.....

For the calculations being done on this thread, it is assumed 100% duty cycle, which I doesn't seem like will ever be the case. Therefore, the duty cycle should be known and factored into the power rating (average over time) and then compared to other sleds...

Though it doesn't matter very much when only talking about the nytro or other yamaha sleds....

 

[ruffryder]

So I called RSI Performance, who has a hi power grip heater element. I think they are doing some testing on the Yamahas for a fix. I asked that they join the site and offer some help.

Good job man, it looks like their setup (RSI) looks to be a good setup for finding a correct resistance. Each grip warmer has two individual elements.

Therefore the grips can be run with all 4 elements (two per side) in parallel, all in series, or in a series/parallel combination like being used above with resistors. It is also possible to not even use both pair in each grip, and use only one! Lots of possibilities for this geek! I am hoping that there will be some combinations that will work.

 

[OneBadWarrior]

Pretty awesome post going here, um I wasn't aware that so many geeks (myself included) were snowmobilers! LOL! I am enjoying following this post and have refrained from adding my $.02 until I have a test bed to share my results from. Which, by total coincidence, is on it's way as we speak! If the grip issue hasn't been resolved by then, I will gladly offer any and all the help I can. Once we figure this out we should bend Yamaha's ear to resolve this problem once and for all!!

 

[BLUEBALLER]

Gade-thrasher, I'm glad you finally see the light. I didn't mean to come across as a prick, but it was getting tiresome explaining the same thing over and over.

Here is my testing plan to calculate power as seen by the hotgrips once I return home.

Measure voltage at idle - record value
measure voltage above 4500 rpms for each of the toggle switchs 10 increments- record values

Install hotgrips & resistor in circuit and measure current flow through said circuit.

measure current at idle - record value
measure current above 4500 rpms for each of the toggle switchs 10 increments - record values

use current measured and voltage recorded to calculate power as seen by the hotgrip for each of the 10 increments

I'm not sure who took the above measurements, but on the nytro, we won't see full output till over 4500 rpms. so they say.

please refrain from calling me a geek. I usually go by nerd.

 

[Timeline]

Nice to see we are all together on this. I took those readings Blueballer. I have to get my sled up in the air securely to run it with the clutch engaged that's why they are at low rpm. I just don't trust that stand.
The Apex is at full voltage when it is at 4000 rpm so I'll try that. Someone else will have to try the Nytro.
Got Apex RTX I'm very interested to see what that controller will do. My feeling is still good about that. I just tried Royal Distributing and they don't carry it but other Hot Grips products. They aren't that far of a drive and I was hoping to pick it up on my way home and try it tonight. On order.

Keep it coming everyone!

 

[Turtle]

Gade-thrasher, I'm glad you finally see the light. I didn't mean to come across as a prick, but it was getting tiresome explaining the same thing over and over.

Cool! - No problem .. I know how hard it can be to get a point across just by typing. I had originally thought you were going to simply add resistors to the stock wiring configuration.

So ... Let us know how it turns out!

 

[r0tax]

So has anyone got an ohm (resistance) reading from the elements that RSI has? I got around to measuring my resistances on mine, and my right is definately an "open"...removed the grips and element last night.

I am planning on going with the RSI elements, but was just curious about resistances..if anyones measured them yet.

And is more resistance = hotter? or the other way around?