Flat battery start

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Just bought a 2013 Sport with original battery. I am trying to replace it, see below thread.
I have read that these bikes’ batteries don’t keep their charge for long if left for any length of time. Mine is in a lockup with no power supply.
So when I return from a month business trip I expect the new battery to be flat. I am fitting Optimate leads to the new battery, so is it advisable to jump start from a , non running, car battery direct? I have also read that it is advisable in these circumstances to run the car positive to the earth on the bike, but this seems impractical. A solar charger would probably get nicked.
Any thoughts gratefully received.
 

Fast Eddie

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Trouble is, getting to the battery on these bikes is just about as big a PITA as it could possibly be!
So, doing it once, to fit switch that you can access easily seems like a good idea IMHO.
 
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Trouble is, getting to the battery on these bikes is just about as big a PITA as it could possibly be!
So, doing it once, to fit switch that you can access easily seems like a good idea IMHO.

Trying to find a switch that suits the bike though does not look easy.
 

BLIGHTYBRIT/SF

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8C59F6A9-35B7-456E-B026-27CC1F03C6BD.jpeg
C7C9CD50-003A-409A-9526-6ED205FA170B.jpeg
Just bought a 2013 Sport with original battery. I am trying to replace it, see below thread.
I have read that these bikes’ batteries don’t keep their charge for long if left for any length of time. Mine is in a lockup with no power supply.
So when I return from a month business trip I expect the new battery to be flat. I am fitting Optimate leads to the new battery, so is it advisable to jump start from a , non running, car battery direct? I have also read that it is advisable in these circumstances to run the car positive to the earth on the bike, but this seems impractical. A solar charger would probably get nicked.
Any thoughts gratefully received.
Here’s my optimate lead permanently on the battery, it’s on an optimate 4 all the time, however I have used a DC to DC charger for another bike when it was in a lock up , u get a fully charged car battery & hook it up with the crocodile clips & the bike battery gets topped up as & when from car battery,it worked for me ( not tried it on the norton ) ,if u could get hold of one of them heavy duty batteries that are used in caravans then even better as they go long periods without a charge
 
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View attachment 6007 View attachment 6008
Here’s my optimate lead permanently on the battery, it’s on an optimate 4 all the time, however I have used a DC to DC charger for another bike when it was in a lock up , u get a fully charged car battery & hook it up with the crocodile clips & the bike battery gets topped up as & when from car battery,it worked for me ( not tried it on the norton ) ,if u could get hold of one of them heavy duty batteries that are used in caravans then even better as they go long periods without a charge

Yup. I’m having that fitted.
 

Tornado

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Could you get a portable jump starter battery? I carry one that claims it can start a car about 8 times. Fits in my riding jacket pocket. Looks similar to this:
J6_w-DFCxLzun7SkPpK_xwCMVkfA7a8XtaZgrZOBLNNqMCp_5g.jpg

Also cab be used for USB device charging and mine has a flash light function. Very handy when you have a dodgey battery condition.
 

BLIGHTYBRIT/SF

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Could you get a portable jump starter battery? I carry one that claims it can start a car about 8 times. Fits in my riding jacket pocket. Looks similar to this:
J6_w-DFCxLzun7SkPpK_xwCMVkfA7a8XtaZgrZOBLNNqMCp_5g.jpg

Also cab be used for USB device charging and mine has a flash light function. Very handy when you have a dodgey battery condition.
In theory u should be able to but , u would need a special lead already from the battery or special adaptor/ connector to get on to the jump starter,I know there are a few inline fuses on the battery ( under the tank the battery is remember ) , in-line fuse on the optimate lead I have has a quick blow fuse in case of too much of a surge I guess, so I don’t how these leads with inline fuses would like it ? , May be Tony A ( our resident go to guy on electronics ) knows more or can give us the heads up on this one ?
 
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Clearly you don't want to send starting current through a small fuse. The jump pack shown above would work but as you stated would need to be attached to the battery terminals directly . OR , attached to the heavy starter cable at the starter . Either way cumbersome and a short out hazard. Why can't he take off his tank before he leaves on his trip and attach some leads to the battery before he puts the bike in the lock up ? That way his tank won't have to come off again. Also , I don't know what he means about running the positive to the earth ? Red to Red + , Black to Black - is how to hook up. If the cable is heavy enough like the jump pack above and with large enough fuse should work.
 
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Also , I don't know what he means about running the positive to the earth ? Red to Red + , Black to Black - is how to hook up.

If I remember I think the classic Commando's were positive earth, maybe that's where the confusion is?
 

Tornado

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If I remember I think the classic Commando's were positive earth, maybe that's where the confusion is?
Correct...+ve earth on the classic Commandos is how they came from factory.
To run the jump pack, I'd run at least a cable from battery positive terminal out to someplace easy to access yet relatively concealable. A higher amp fuse in line near battery is a good idea also (say 20-30 amps). I believe these jump starters work by quickly supplying a charge
to a low main battery, and do not claim to start a car without the main battery doing some of the heavy lifting. Afterall, the jumper leads are no where near the gauge of main battery leads on any car.
Put some kind of terminal on the cable (of similar or greater
diameter as the jump pack
lead)...preferably the terminal could have a cap of some kind....thinking like the Battery Tender type leads with cap.
To jump, hook positive bike cable to red jump clamp, then put black clamp to a good ground on frame/engine.
I've learned that my jump starter has a special behaviour when about to perform the jump. The square box on the red lead has LED that blink to confirm correct polarity but also it shuts off output after more than 20-40 seconds of no activity...so once connected and getting all ready blink status, don't hang around before trying starter.
 

contours

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I know I've mentioned this item too many times already, but it solved all my battery drain problems. Especially when I'm away from home for the day.

Antigravity-Battery-12v-Jump-Starter.jpg


I got the heavy duty adapter along with it and installed it as my lead from the battery.
 
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My 2013 Sport came with an optimate charging lead as standard. The connector was tucked inside the rear shock top bolt recess on the left hand side (UK near side).
 
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one option if no power in your lock up try a large Leisure battery lower discharge rate
 

Bluedog 55

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Could you get a portable jump starter battery? I carry one that claims it can start a car about 8 times. Fits in my riding jacket pocket. Looks similar to this:
J6_w-DFCxLzun7SkPpK_xwCMVkfA7a8XtaZgrZOBLNNqMCp_5g.jpg

Also cab be used for USB device charging and mine has a flash light function. Very handy when you have a dodgey battery condition.


I had to use one like this yesterday connected at the starter motor and earthed on the head bolt, I was on a three day ride had done 450km first day and 250 km 2nd day woke up to a cold morning frost the bike wound over strongly but wouldn't fire, 2nd time not so strong then next the dreaded clicking, when I did hook it up I had to give it some throttle too the standard start wouldn't cut it, the bike is 3 1/2 I had from new and it has always apart from overnight trips been on trickle charge, I'll get a new battery but I think I'll be investing in one of these too.
 
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