V7 III - Disposable Alternator Capacity?

[GreyGooseGuy]

Would any of you happen to know, of the V7 III's 268-watt alternator output, how many of those watts are mine to play with at 3,000 RPM? I have an Aerostich heated bib that I've used with great benefit over the years. It "only" draws 30 watts. That would be in addition to my GPS, which is unlikely ever to draw more than 6 watts, and usually less.

I ordered a digital voltmeter for the bike this morning. I guess that will tell me, as voltage drops with increased electrical load, when I've gone too far... no?

Thanks!

[moto-uno]

  You'll have lots left over .  Peter

[Vagrant]

I run a heat troller usually at 40% with a Gerbing jacket liner. I run oxford heated grips at 30-40% a Garmin and a Valentine radar detector. I know I'm right on the edge of discharge because the center light on the grips starts flashing meaning low voltage at lights. I'd like to disconnect the headlight for safety or replace it with a LED but seeing as I never ride at night the cost makes no sense. I shut off the gps when I remember because I really just use it for a speedometer anyway. and try to shut off everything else 5 minutes before shutting down. most importantly never run it below 4000 RPM! then2015 V7 had plenty the V7III is weak at best.

[pyoungbl]

3K rpm is too low for full electrical output.  You won't see full output until at least 3500 rpm and 4000 is a much better sweet spot all around.  After you install your volt meter you'll be able to reach your own conclusion and I believe you'll see exactly what I'm predicting.  It's all too tempting to get into 6th as soon as possible, thus plodding along at 3K rpm.  On a Guzzi you are much better off getting the engine to spin at about 4K rpm.  You are not causing any damage to the motive lump, it's made for that rpm range.  Drop down a gear or two and keep the engine spinning.  Much better all around.

Peter Y.

[GreyGooseGuy]

Thanks, everyone. I was trying to be conservative with that 3,000-RPM figure. It's happier (and so am I) at or above 4,000... just being cautious.

At what reading on the voltmeter am I concerned that I'm burning more watts than I'm replacing?

[ohiorider]

3K rpm is too low for full electrical output.  You won't see full output until at least 3500 rpm and 4000 is a much better sweet spot all around.  After you install your volt meter you'll be able to reach your own conclusion and I believe you'll see exactly what I'm predicting.  It's all too tempting to get into 6th as soon as possible, thus plodding along at 3K rpm.  On a Guzzi you are much better off getting the engine to spin at about 4K rpm.  You are not causing any damage to the motive lump, it's made for that rpm range.  Drop down a gear or two and keep the engine spinning.  Much better all around.

Peter Y.

Sounds a lot like the Bosch charging system on my 1991 BMW R100GS.  I think maximum alternator output is 280w.  I've been under the impression for years that this particular alternator doesn't output a lot of juice anywhere under 3000rpm.  So I make sure to stay in a gear that keeps me somewhere around 3500 rpm.  These older BMWs came with large batteries to compensate.  I think the most recent replacement battery I installed was a 26 ah.  Over the years, I've ridden this bike on several day rides and multi day trips with an older Widder vest and heated grips (don't know wattage.)  No issues, and I'd think the new Guzzi V7 would have a better charging system than a nearly 30 year old bike.

Just thought .... the old Beemer doesn't have many devices that draw current.  No fuel pump, no ABS, and I've installed a multi-LED taillight.

[Kiwi_Roy]

The V7iii will not handle a heated vest and gloves around town, I learned that the hard way, Gerbing gloves are ok but the Gerbing vest is over the top and will result in having to push start.
It's ok if you remember to turn off the heat 10 minutes before you stop.
Girbing sent me one of their new Bluetooth controllers, its very nice I fitted the power controller under the LH side cover with the controls at the bars, no wires.

[Perazzimx14]

A volt meter is the best way to monitor the electrical output of the system. As mentioned peak electrical output will not happen sitting at red lights or riding through town so it easy to start consuming more power than the bike is creating.

[Dave Swanson]

I suppose the new Night Pack model with all LED would have more available electrons for heated gear

[blu guzz]

I took a ride on my 1984R100RS on a very cold day around 1998 to a very large motorcycle store south of Columbus, Ohio.  It was there and then that I bought my first ever pair of heated gloves.  It was like I had died and gone to Miami.  But, I was warned to turn them off below 3000 rpm.  Sure enough, the alternator light would come on if I was coasting down.  I later got the matching vest and had to be even more careful, but oh, the warmth after nearly 20 years of freezing my butt off.  As far as I know, by being careful with this, I never did any damage to the charging system.
Stay warm and enjoy.

[antmanbee]

Gerbing 12V Vest Liner Technical Specs: Max Heat: 135° F @ 54W; Power: 12V DC 4.5 Amp

I use this vest on my 750 Breva and also have heated grips. I usually do not have them on full power.
I use a PWM controller which will reduce the Watts used at less than full on settings.
If I was having a problem with not enough alternator output I would just change the headlight bulb to LED. That is the biggest draw.
I have never had my bike not start due to battery drain down from the vest.
I typically don't ride a lot where I am idling at lights and in traffic.

[n3303j]

Spent a week in DC doing local day tours on my BMW R100RT. Averge speed in DC seems to be 3 mph. Every day I'd see a bit less on the Voltmeter. Thanks to BIG Odyssey we survived the week. The highway run south to The Dragon put everything back to rights. Ideal situation would have been to put the bike on the charger at each day's end. Opportunity did not present itself.

[Kev m]

No issues, and I'd think the new Guzzi V7 would have a better charging system than a nearly 30 year old bike.

I believe the limiting factor is physics and not the year of manufacture.

I.E. rotor on the engine of the crankshaft design means it can spin so fast in both cases, that's why belt driven alternators were adapted to later designs including the CARCs and Cali 1400s.

I don't know the reason/logic they went to the wet alternator though, which actually dropped capacity slightly.

Then again I've never had a deficiency in the charging system on any of my Guzzis from load, though I don't use heated gear often.

I do believe the most common answer is to go full LED on the lighting thereby freeing up a bit more capacity.

[ohiorider]

Kev, I recall reading 'somewhere,'  that BMW increased the clearance between the crankshaft-mounted alternator and the stationary field windings because when they were developing their R90 bikes for the track (think Reg Pridmore and early Superbike Racing,) the bikes began developing some flex in the crankshaft at high rpm, causing the rotor to make contact with the stator windings.  I'd have to research this to find out whether it's truth or fiction.  Maybe someone else versed in Beemers knows.

[moto-uno]

  Are we getting away from the subject ? . Entertaining as it is .  Peter
And yes a voltmeter should tell you what's happening with your charging system.

[GreyGooseGuy]

Thanks, everybody. I appreciate your input. Since night riding is something I plan to do occasionally, I looked into a full LED headlight conversion, rather than just a bulb swap. The price tag, IIRC, was somewhere north of $900 all told. So that just ain't gonna happen.

I'll try the heated bib, carefully, when I need it, and will monitor the voltmeter.

Thanks again,

[moto-uno]

  There are 30 watt halogen head light bulbs that are pretty bright and cut the current draw in half  .
  Those LED kits are over the moon price wise !   Peter

[n3303j]

https://tinyurl.com/ybw8umpx

I've installed the previous version of this company's H4 bulb in 3 bikes.

Lower drain and so far working fine. One just completed cross country round trip.

[Huzo]

A zero centre ammeter will tell you if you’re “ pushing or pulling”.

[GreyGooseGuy]

A zero centre ammeter will tell you if you’re “ pushing or pulling”.

True, but much more of a PITA than I'm looking for.

[Andy1]

I use a voltmeter on my R100R BMW that is a small LED lamp that changes colour depending on voltage - green when good, orange when a little high or low, red when out of spec.  It is permanently wired in (via a fuse) so whenever the key is on it is working and is mounted where I can see it on the handlebars.   It is superb at helping to show up problems as 25 year old charging systems can fail!  It would also show if your jacket was lowering the voltage.
AndyB

[Zoom Zoom]

You're on the right track getting a volt meter. Managing the extra watts is nothing new. Many of us have played that game over time. When I had my EV, running down the road at speed was not too much of a problem. If I went into a town where speeds were lower, I would turn off my aux lights and/or my heated gear just to keep the volt meter in the green so to speak.

It's less about what you have and more about managing what you have. 

John Henry

[Zoom Zoom]

Question for the modern small block guys:

Is there a volt meter in the menu on the LCD part of the dash???

John Henry

[moto]

I use a voltmeter on my R100R BMW that is a small LED lamp that changes colour depending on voltage - green when good, orange when a little high or low, red when out of spec.  It is permanently wired in (via a fuse) so whenever the key is on it is working and is mounted where I can see it on the handlebars.   It is superb at helping to show up problems as 25 year old charging systems can fail!  It would also show if your jacket was lowering the voltage.
AndyB

Ditto. Excellent description of what I installed on my Buccaneer, and its usefulness. (Except that mine has a separate indication for over-voltage.) For anyone watching this thread who might be interested, England has a great, inexpensive fabricator, Gammatronix. About $15 instead of the $60 or so for an inferior US brand:





(Be careful not to click on the one priced at $1355.  )

Moto

[Kev m]

Question for the modern small block guys:

Is there a volt meter in the menu on the LCD part of the dash???

John Henry

Nope, but maybe with the Bluetooth data thingie if you installed one I forget.

[Zoom Zoom]

Thx Kev. You would know.

ZZ

[Kev m]

Nope, but maybe with the Bluetooth data thingie if you installed one I forget.

Just checked, yes the multimedia platform offers that display on hemi head smallblocks.

[greer]

https://tinyurl.com/ybw8umpx

I've installed the previous version of this company's H4 bulb in 3 bikes.

Lower drain and so far working fine. One just completed cross country round trip.

Plug and play as stated?  Nothing oddball about the beam pattern?  From reading the question/answer section this looks to be a listing for two bulbs, seems like a heck of a deal.

Sarah

[n3303j]

Plug and play as stated?  Nothing oddball about the beam pattern?  From reading the question/answer section this looks to be a listing for two bulbs, seems like a heck of a deal.

Sarah

Mine (previous iteration) required me to remove some flash from the hole in the Bosch reflector. 5 minute with a Dremel.



Also the point in the picture above put a slight dark wedge into the low beam pattern. Conveniently this was the spot filled by a rider in front of me. So he didn't have my full backlight to deal with spoiling his night vision.



The newer bulb seems to have slightly reduced heat sink diameter so will probably just drop into the shell. It also does not have the point so there might be no shaded area whatsoever.

Nice thing about Amazon is the 30 day trial period. If they don't fit or work as you expect just click return and they supply a post paid return label for a convenient refund.

[Idontwantapickle]

Mine (previous iteration) required me to remove some flash from the hole in the Bosch reflector. 5 minute with a Dremel.



Also the point in the picture above put a slight dark wedge into the low beam pattern. Conveniently this was the spot filled by a rider in front of me. So he didn't have my full backlight to deal with spoiling his night vision.



The newer bulb seems to have slightly reduced heat sink diameter so will probably just drop into the shell. It also does not have the point so there might be no shaded area whatsoever.

Nice thing about Amazon is the 30 day trial period. If they don't fit or work as you expect just click return and they supply a post paid return label for a convenient refund.

Ron, I have ordered the new version. I had been contemplating LED for the LeMans as the headlight is so-so at best. I'm hoping it will help with daytime visibility as well as night riding. Since they come in pairs I'll have to flip a coin to see if the other goes in the Eldo or BMW!

Hunter