Will I have enough juice?

[dasadab]

Hi,

Just bought an '09--love it! I want to add a pair of Motolights for being seen. Great lights. I had them on my old BMW (bah!) and they are great lights. I get the amber bulbs and you get a great triangle of low yellow lights and the white headlight. A pair draws 5.8 amps. If I ride two-up and use Gerbings heated liner at 6.4 amps per jacket or 12.8 amps total for the jackets, I am then up to 18.6 amps. I then want to add heated grips and a GPS. Will I have enough juice to run everything? Thanks. Dean

 

[Capt. Bob]

Here's a start. Clicky

 

[Zorlac]

"Will I have enough juice to run everything?"

No, not at the same time.

 

[Silent]

If I fire off my FF50's while my grips and jacket liner are on med-high, my grips shut down. So I'd guess no.

 

[dnac]

Hi, Just bought an '09--love it! I want to add a pair of Motolights for being seen. Great lights. I had them on my old BMW (bah!) and they are great lights. I get the amber bulbs and you get a great triangle of low yellow lights and the white headlight. A pair draws 5.8 amps. If I ride two-up and use Gerbings heated liner at 6.4 amps per jacket or 12.8 amps total for the jackets, I am then up to 18.6 amps. I then want to add heated grips and a GPS. Will I have enough juice to run everything? Thanks. Dean

Here is a list of everything that is on the bike and the wattage it consumes (from the service manual for an 08 model). The LED lights are negligable, all of them on at once are considered to consume 1 watt. Note I estimated the cooling fan because I could not find a listing for it in the manual.

Alternator Output 590 watts

Neutral led

Turn Signal Indicator led

High Beam indicator led

Engine Trouble led

Headlight High Beam 60W x 2 120

Talilight 5W x 2 10

Brakelight 21W x 2 42

Turn Signal Front 21W each 42

Position Lights Front 5W x 2 10

Rear Turn 21W each 42

Meter Light led

Horn 36

Turn Signal Relay 4

Fuel Pmp 72

Radiator Fan (estimate) 60

Total 438

Excess Capacity 152

So with everything running All lights on, high beam, brakes applied 4 way and in neutral while beeping the horn you have 152 watts left. 19 amps (your gear minus the garmin) x 14v = 266 watts which means you are short 114 watts which is very bad.

So to be more realistic if you were in a condition of Normal Running with the Fan, Turn Signal, Brake light and high beam on you would have 230 watts of excess capacity which is still short of the 266 needed.

You get the idea, just add and srbtract the wattages if you are over the max capacity its like an overdrawn checking account very bad (probably costly too).

 

[weekend rider]

You use 12 volts for your calculation not 14

 

[dasadab]

Thanks a lot for the information. I am going to add the Yamaha heated grips which I understand act like a regulator, i.e., they produce less heat if the electrical load starts going into the negative. I think that the Gerbings figures are for max. heat, which, for me is pretty rare to use. It seems that if my wife and I are both using the Gerbings, safe bet is to turn off the Motolights. Its a little like "Apollo 13" when they are trying to find a few extra amps. Thanks a lot for the replies. I really appreciate them. Dean

 

[dasadab]

You use 12 volts for your calculation not 14

Not sure I understand the statement. As I understand it, the battery would ideally like be in a position where the usage is not drawing it below about 13.7 to 14.5 volts?

 

[dasadab]

Let me see if I understand this. Gerbings says its heated jacket liner draws 77 watts at 12 volts. The FJR produces 14 volts at 5000 rpm. Therefore, for purposes of my calculations: the Gerbings draws 55 watts if I use 14 volts (77watts divided by 14 volts). Therefore, assuming I am over 5000 rpm, I should use 55 watts, not 77 watts as the basis for my calculation?

 

[Khunajawdge]

If I fire off my FF50's while my grips and jacket liner are on med-high, my grips shut down. So I'd guess no.

Well here, I beg to differ! I use a Widder 44 watt vest, a pair of 14 watt (velcro attached) heated grips from Aerostitch, AND, a set of Heli FF 50's and "if" I'm running at 4000 + RPM for a "duration", I am GOOD with ALL of these ON for hours on end (save = of course running into an urban center with with low RPM's at stoplights etc). I am on a Gen 1 FJR, have wired ALL the accessories through bigger wire size (10) and use a "remote" fuse box. Lastly, have an upgraded Electro(?) alternator (supposedly giving me an additional 100 watts or so) over the stock unit. No worries, and I sometimes go far from home....?

I use my Datel meter to monitor it all. 14+ is good, 13.2 - is getting pretty low, so I shut something off.

 

[C&C]

Add one more farkle (a volt meter), then monitor your voltage. There are tons of discussion about volt meter uses and how to monitor your electrical usage. And remember, in order to get all those 590 watts, you need to be turning 5,000 rpm's; that's going to put you into the, going way-too-fast category unless you're in a lower gear or on the autobahn.

 

[Checkswrecks]

Add one more farkle (a volt meter), then monitor your voltage. There are tons of discussion about volt meter uses and how to monitor your electrical usage. And remember, in order to get all those 590 watts, you need to be turning 5,000 rpm's; that's going to put you into the, going way-too-fast category unless you're in a lower gear or on the autobahn.

Best answer yet!

 

[lnewlf]

How much draw for the ECM and the four injectors?

 

[Zorlac]

Ummm, less than the max? :dribble:

 

[RadioHowie]

Ummm, less than the max? :dribble:

Zippy hits a homer!!!

 

[wfooshee]

Zippy hits a homer!!!

And BEST EVAH relationship between avatar and post!!

 

[RadioHowie]

Zippy hits a homer!!!

And BEST EVAH relationship between avatar and post!!

+1

[SIZE=8pt](us Floh-Uh-duh boys gots to stick tuhgetha!)[/SIZE]

 

[lazbm]

Page 3-27 of Owner's Manual:

======================================================================================

The accessory connected to the auxiliary DC jack should not be used with the engine turned off, and the load must never

exceed 30 W (2.5 A), otherwise the battery may discharge.

======================================================================================

Go figure! I read it as the spare capacity that Yamaha is willing to stand behind is 30W before the battery starts discharging.

 

[dnac]

Let me see if I understand this. Gerbings says its heated jacket liner draws 77 watts at 12 volts. The FJR produces 14 volts at 5000 rpm. Therefore, for purposes of my calculations: the Gerbings draws 55 watts if I use 14 volts (77watts divided by 14 volts). Therefore, assuming I am over 5000 rpm, I should use 55 watts, not 77 watts as the basis for my calculation?

No the jacket will dissipate more wattage when the voltage is raised. Kind of like a light bulb burns brighter and hotter if the voltage is raised. Just put a 6 volt rated bulb in a 12v socket and turn it on, it will be very bright and very hot for a very short time.

Here's why, in a DC circuit E (Electro Motive Force - Volts) is equal to I (current - amps) x R (resistance - ohms)

And P (Power - Watts) is equal to E x I

So at 12 V with a current of 6.4 amps the wattage is 12v x 6.4amps = 76.8 watts and

At 12v with 6.4 amps the resistance of the wires in the jacket is E/I = R or 12/6.4 = 1.875 Ohms

Since ohms don’t change because the wire in the jacket is a fixed length and type the Resistance can be used to calculate the wattage dissipated at different voltages.

So at 14v and a 1.875 ohm load the current would be 14/1.875 = 7.47 amps

and 14v x 7.47 amps is 104.5 watts so higher voltage causes more watts to be dissipated.

I used 14 in the previous calculation because that is a worst case scenario (most watts used), you can use 12v however that reduces the safety margin of the calc.

Its much easier to connect a voltmeter and turn stuff off when the meter shows low battery voltage.