Ulysses charging capacity

[miked847]

Not being electrically proficient, can anyone tell me how much excess capacity the system has after supplying the bike's needs, for accessories like, driving lights and heated grips, vest, etc? The Uly has a 494 watt 38 amp alternator.

Thanks in advance.

[TomD]

While I can't answer your question directly; I think I can't point you toward finding an answer. I'm quite sure you have enough capacity to do at least some of what you want. The quickest way to find out is with a clamp on ammeter designed for DC amps. I would think any auto shop that specializes in charging systems would have one. I work on boats and have one. It would take all of about 2 minutes for someone to do this start to finish. Start the bike up, turn everything on and take a reading. Subtract this from the rated output and you have your theoretical reserve. I say theoretical because most charging systems are not designed to put out at maximum for long periods, things get hot. I would suspect people who run their charging system near maximum output experience greater stator and regulator failures than those that don't. 25 or 30% in reserve, in other words only using about 30 of your 38 amps, would sound reasonable to me. If I'm wrong or if someone has direct knowledge, please jump in.

Tom

[Cadiero]

38 amps is alot. You should be good. Also since it is a 3 phase system it does generate less heat so you can run less of a safety factor than the older systems.

Just run a volt meter, when it drops shut something off. That's a simple way of ensuring you are in the safe zone while riding.

[miked847]

Any idea what that number might be? I'm thinking I would like to be able to use about 250 amps for add on accessories. Does that sound doable or is it hard to say?

[TomD]

Originally Posted by miked847

Any idea what that number might be? I'm thinking I would like to be able to use about 250 amps for add on accessories. Does that sound doable or is it hard to say?

250 amps is an awful lot of current; 3000 watts at 12 volts. I'm sure you meant 250 watts and at 12 volts this is almost 21 amps. This is more than half the total capacity. I really think this is a sizable load and you should find out what the bike actually draws and how close you are to maximum output. The test I described is just a matter of clipping the meter on to the positive or negative lead, which ever one is easier, starting the bike up and reading a number. Auto and marine alternators are three phase also. I can tell you absolutely that unless the alternator is "hot rated" it will not stand up to frequent prolonged maximum output. Special alternators carry extra special pricing. While I realize this is not bike specific, I do make part of my living diagnosing and repairing charging systems. I really wish someone with first hand experience would jump in and post a definitive answer. Until that time, I urge some caution with that size load. The test I'm talking about, requires only that the battery wiring be exposed. No disassembly of anything other the the seat.

Tom
.

[miked847]

Originally Posted by TomD

250 amps is an awful lot of current; 3000 watts at 12 volts. I'm sure you meant 250 watts and at 12 volts this is almost 21 amps. This is more than half the total capacity. I really think this is a sizable load and you should find out what the bike actually draws and how close you are to maximum output. The test I described is just a matter of clipping the meter on to the positive or negative lead, which ever one is easier, starting the bike up and reading a number. Auto and marine alternators are three phase also. I can tell you absolutely that unless the alternator is "hot rated" it will not stand up to frequent prolonged maximum output. Special alternators carry extra special pricing. While I realize this is not bike specific, I do make part of my living diagnosing and repairing charging systems. I really wish someone with first hand experience would jump in and post a definitive answer. Until that time, I urge some caution with that size load. The test I'm talking about, requires only that the battery wiring be exposed. No disassembly of anything other the the seat.

Tom
.

Whoa! Tom, you are so right. I meant 250 watts. At the max, I'm adding 200 watts of driving lights and about 50 in heated apparel.
I'm unfamiliar with the meter you're describing. It's as simple as a one-point connection?

[TomD]

Originally Posted by miked847

Whoa! Tom, you are so right. I meant 250 watts. At the max, I'm adding 200 watts of driving lights and about 50 in heated apparel.
I'm unfamiliar with the meter you're describing. It's as simple as a one-point connection?

It has jaws that open and simply close around the wire. No connections are disturbed. The most common are AC amps only. They are used a lot around electric motors and air conditioning compressors. DC capable meters are just a few dollars more, but most guys never use the DC feature and don't bother to pay the difference. The link below has a picture. I am not familiar with that brand and don't think there is a lot of difference in the lower priced units. I am not recommending that you buy one, just find someone who already has one. You're only going to use it once for 20 seconds.

Tom

http://www.calright.com/pd_430.aspx

[miked847]

Originally Posted by TomD

It has jaws that open and simply close around the wire. No connections are disturbed. The most common are AC amps only. They are used a lot around electric motors and air conditioning compressors. DC capable meters are just a few dollars more, but most guys never use the DC feature and don't bother to pay the difference. The link below has a picture. I am not familiar with that brand and don't think there is a lot of difference in the lower priced units. I am not recommending that you buy one, just find someone who already has one. You're only going to use it once for 20 seconds.

Tom

http://www.calright.com/pd_430.aspx

Thank you Tom for your time in replying. I've purchased a Kuryakyn led battery meter which will get installed on the triple tree so l can keep an eye on things in real time. I will seek someone locally with a DC unit as you described though as well.
Best,
Mike

[TomD]

Cadiero's post opened with 38 amps is a lot. Looking at this got me thinking and 200 watts of auxiliary lighting is also a lot. Normal low beam is 55 watts and I believe high is 65. 200 watts of lighting, if it is up front, is going to blind on coming traffic two counties away! Are you doing this for off road use or could you have your numbers wrong?

Tom

The meter sounds like a good idea. I'd really like to know what you are using this for and I'm really interested in the end result. If all goes well, some moonless night point the bike toward Sandy Hook, New Jersey and I'll wave to you.

[miked847]

Tom, the aux lights are 65 watts each, and I wired the 65 watt high beam to be on at the same time as the low beam, which is 195 watts addl. to the elec. load. All are switched independently. One of the reasons for the lights is the riding I do on back roads in areas of very high deer population. I also will likely never forget one rainy late night driving through S. Dakota on new pavement that had not been striped yet. Couldn't see squat. Also, because of the wet condition and the inadequacy of the stock light setup, if there would have been a delaminated truck tire carcass in the road I couldn't have seen it before something bad might have happened. Unsafe? Probably, but at the time, we were not in a position to pull over and check into a hotel because there were none, and slowing down to 35 or 40 on the interstate wouldn't have been a good idea either. It was one of those "you would have had to have been there" situations to understand. We've all had them. I'm in the over 50 crowd and the night vision wasn't what it was 30 years ago. I know that blinding oncoming traffic is dangerous too, so I'm sensitive to that and won't ever ride with the brights on or with misaligned lights.
Mike

[TomD]

Mike,

I'm in the pushing 60 real hard crowd and you're right about the night vision. I've found wearing my glasses helps a lot. I actually try not to be out on the bike after dark, but it does happen and I'm thinking about auxiliary lights on my Fatboy and doing something with the bulb on my YZF 600. Living in New Jersey, one begins to forget that there are places without steady traffic and street lights. Good luck with the project and I'd love to know how you make out.

Tom

[miked847]

Originally Posted by TomD

Mike,

I'm in the pushing 60 real hard crowd and you're right about the night vision. I've found wearing my glasses helps a lot. I actually try not to be out on the bike after dark, but it does happen and I'm thinking about auxiliary lights on my Fatboy and doing something with the bulb on my YZF 600. Living in New Jersey, one begins to forget that there are places without steady traffic and street lights. Good luck with the project and I'd love to know how you make out.

Tom

Tom, I've had the setup on the bike now for a couple of weeks and the testing I've done so far is good. I haven't plugged in the heated clothing, but I added heated grips. With the grips on high and with 200 watts of lighting, the alternator seems to keep up. The battery meter fluctuates slightly while underway, but stays in a favorable range.

Mike