My sons 797 plus has a flat battery, strange since it’s only 6 weeks since He rode it last. A couple of questions. 1. Can the battery be charged whilst in the bike? The reason I ask is that when there was a tracker fitted ( that has a low voltage cut off thingy) the fitter had a huge problem getting the captive nut in the battery terminal to catch and I’d rather not have to go through that pain and remove the battery. 2. What is the best charger/ optimiser to use for breathing life back into the battery? 3. I note some chargers are optimised for canbus systems. Does the 797 need a canbus charger?
Sounds as if there is no optimate lead fitted in which case fit one asap as it makes life much easier.
In this instance, No. For the following reasons. Assuming the terminal voltage is near zero and a limited charger , say 3amps... Then as it attempts (and fails)...to recharge there will be a slow climb in voltage.... this can cause miss writes to software driven devices.
If you have a tracker fitted, I'd definitely leave it connected to a Optimate type charger full time. One of my bikes has a tracker and if I left it for a month, the battery would be flat.
Put a piece of plastic behind each terminal bolt so that it protrudes to the max. Makes putting the nuts on much easier.
Cut a 5mm long bit off the acid breather tube and push it under the captured nut to help...... and feel real good.
Im going to check the voltage tomorrow, if its greater than 10.5v it should be ok? Im going to search for a charger that will condition a battery as well as charge and maintain, Optimate 4 or something like that.
Daughter managed to completely flatten the battery on her CG125 by leaving the heated grips on. It was so flat that my smart charger didn’t recognise it was connected to a battery and wouldn’t switch on. Managed to retrieve the situation by jumping the CG and leaving it running long enough to get enough charge into it to enable the smart charger to do its thing. Been fine ever since but I think if the battery had been left flat for more than a few hours it would have been a very different story.
Not sure if it’s my optimate, as it’s an older one, but it won’t charge a flat battery. I got a cheap trickle charger from a garage and use that first.
I tried bump starting it but ended up with a locking back wheel. If there’s juice in it I’ll try a jump start and take it for a run
Gents please do not waste your time on batteries that have been below 10.5V. Use a drop tester and see how much useful capacity is left (CCA). Measuring terminal voltage alone will not tell you much. The fact that you can get the terminal voltage back up to 12.8 and it starts a bike doesn't mean it's NOT cattle trucked.
Yes if the terminal voltage is above 10.5V then use a charger to fully charge it. If not, bin and start again.
Well terminal voltage was 4.6v so decided to try the optimate4 which says it’s able to recover from 0.5v! Took the battery out of the bike and put it on for about 24hrs until the lights told me to take it off. Bike running was reading 13.4v, obviously output of the bike charging. Took it a run for half an hour and when switched off, read 12.4v . Happened to stick the charger on my multi, which has had a few runs out since October and started every time, it diagnosed the battery wasn’t right, so the charger is currently in test mode, to see if that battery will keep it charge! I’m gonna check the Monster in the morning to see how well it has retained the charge, although my gut feeling is it’ll be bad news! 1 certainly hope I’m not having to buy 2 batteries! I’ll also be getting a quote for getting power to my shed, can’t be leaving windows open to run an extension cable to my shed, which has no power
Running an extension lead into the shed may not be the optimum solution, but it's a whole lot better than having to buy new batteries every season! In the winter I have Optimates on the car, quad bike and Monster just for the peace of mind - knowing they will always start!
