Motorcycle Camping

[Dagwood_55]

I've got a motorcycle camping trip coming up in May. Probably 8 or 9 nights of tent camping with no power. Our camping will be boondocking
in tents.

I'm willing to buy a Z1 or Transcend Cpap and a supporting battery, but I'm concerned about fully charging the battery
each day from my bikes cig charger. I have information from another bike traveler in another forum that has and uses a Z1
cpap with the little battery thay sell that fits in the little case. He has the same bike as I do and he says he can only get
a 30% charge in a full days riding, so he has to use 3 batteries to keep up, which would be quite expensive.

Anyone been down this road with advice?

[realshelby]

I don't have the Z1 factory battery. Quite expensive for the convenience it offers. I don't know how that battery is set up to be recharged, but if not charging off the bikes power outlet there is either something wrong with that outlets available power ( think BMW with CanBus ports that shut off if power parameters are exceeded ) or the charger being used isn't putting out enough when converting the power.

The Z1 can apparently run directly from a 12v power source. You can buy a power adaptor with the Z1 that has battery cable clamps on one end. I would buy a small AGM battery for a mower, scooter, or whatever was a good size for you and power the Z1 directly from it. Then you could direct wire it to the bikes battery ( fused of course ) and charge directly from there. I would probably adapt my Gerbings heated gear power outlet for this. That will insure a fully charged battery. If you get a big enough battery it could operate 2-3 days easily without recharging if necessary.

[Danalex]

something's wrong if a full day's riding won't fully charge the small Z1 battery.

On my old GS there was a space under the tank for the ABS module which mine didn't have so I put a second Odyssey PC680 and it fit just fine.

[Dagwood_55]

Thanks for the replys. I'm not even close to knowing much about figuring electrical stuff, but is there
a way to tell if a certain bike will charge a certain battery and how long?

[realshelby]

I have voltmeters on all my motorcycles. If you are over 13 volts you are charging. 13.8-14.2 is optimum range. If your bike is able to maintain that, the battery is being fully charged.

There could be a complication. The batteries that come with the Z1 package are Lithium Ion. These require a higher voltage to fully charge. 2-5 tenths higher volt to charge them correctly. If your friends bike is marginal, it may simply not be able to charge that battery.

But only charging it to 30%? That is suspect to me. Has to be something else going on in my opinion.

[CapnLoki]

Thanks for the replys. I'm not even close to knowing much about figuring electrical stuff, but is there
a way to tell if a certain bike will charge a certain battery and how long?

The problem is likely not with the bike, its with the charger & battery. I don't have this pump (and haven't had a bike in 50 years) but that won't stop me ...
First, the pump is very low power, typically about 3 amp-hours a night (at 12V) which is somewhat less than the full sized pumps. Not knowing the pressure, or the efficiency of the charging system we could round that way up to 8 amp-hours of charging and still only have a one amp load. Its likely that the alternator puts out at least 10 amps and probably a lot more. Harley's are around 32 amps. Of course its possible that there is a lot of additional load, but its a good bet there's at least an amp left over. If your system is actually overloaded, you'd probably know it by the lights dimming at idle!

On the other hand, charging a small battery from 0 to 100% with a small charger is problematical. You might get to 60% in a hour, but then it starts to slow down. many systems will say something like 85% in 5 hours, 100% in 24 hours. Its quite possible that if the day's run is under 4 hours, you're simply not going to get a full charge. This problem is common to most battery systems. Cruising sailboats (and off grid RVs) solve this by running the battery bank from 50% to 85% (for lead acid) so that they stay in the "sweet spot" of the charging curve. It means that they need a bank 3 time the daily load so that they only charge for a few hours a day. Tesla's often run from about 30% to 80%. In general, the easiest solution is to add battery size, since a larger battery will accept a charge faster.

The advice of adding a small AGM scooter battery is good, though there is a weight problem. I use a 35 AH battery at home, but that weighs 24 lbs. You could go down a size - anything about about 15 ah would give a a fair reserve compared to the 3ah one night load. I hope this makes some sense - please report back any observations.

[realshelby]

I just weighed a motorcycle battery I have here. 9 lbs, 6 oz. Which is still quite a bit of weight, but not too large in size. It has an 11 amp hour rating. NAPA 12-BS.

[Danalex]

here's a whole long thread on Adventure Rider about cpap on a motorcycle.

https://advrider.com/f/threads/cpap-is- ... no.825663/