There are specific connections for jump starting the bike. The positive is under the seat with a plastic cover and the negative is on the right cylinder head. I keep mine hooked up to a ctek charger 24/7. I have the positive lead connected to the under seat busbar and the negative connected alongside it where the busbar is bolted to the frame. I think if you are plugging a charger into the USB connection under the tank it needs to be a specific canbus compatible type.

 

The jump connections are as @Bobber101 says. It depends where and what you are talking about when you say you are charging using the optimate connector. Can you be more specific or provide a photo? That might be why the bike battery is not charging despite hooking up a charger.

 

The optimate is connected under the seat to positive
And the negative to the bolt which appears to cover access to the battery . Perhaps the tender I have just won’t work with this bikes system?
Anyway I used a standard 12 volt charger to recharge . Attached at the right side stud for negative and at the positive stud under the seat. Charged in a few minutes and started fine.
Recommended tender for this bike?

 

I'm going to be honest and say I am still not clear on where this "Optimate" connector is connected to and if this is a genuine Optimate connector. It sounds as if it is a sort of "pigtail" arrangement. The positive side should go to the positive bus bar connection under the rider seat to the rear of the tank and the negative to a good earth point on the bike. I used a bolt on the cast alloy seat brackets (towards the middle) to earth an accessory "cigarette lighter" type of socket to power a compressor with good results. I'm not clear where the earth is that you are using - sorry. Are you absolutely sure the "optimate" connector is wired correctly?

I apologise if you already know how to test for a good earth, but I use a multimeter set to resistance scale. If I touch a known good earth point with one meter probe (such as the jump start earth bolt) and touch the earth point you are thinking about using. If you get zero or a very low resistance then it's a good earth point.

There is a big battery tender thread on this forum which you should look through for tips and suggestions of what battery chargers (tenders) are used with our bikes. I've provided a link below:

Battery Charging/Tender Thread (Merged)

I tried charging my R9T battery using a cheap battery tender with a adaptor plug into the aux socket, it wouldn't work, I tried turn on the ignition and off, it worked for 5 min then off, then I found this charger on the website TecMate OptiMate 4 Dual Program Battery Charger for BMW CANbus -...

www.ninetowners.com

As always (and no offence intended) if you are unclear or hesitant about tackling wiring on your bike I would trust the work to a mechanic or auto electrician as it could prove safer and less hassle in the long run.

 

It is a pigtail plug in with an "OPTIMATE READY" tag on it. the pigtail connects to the positive post under the seat, and the negative portion of the pigtail connects by a screw in bolt attaching a cover over the battery well , below and behind the gas tank. It was installed when I purchased the bike new, so I never asked about it. I wonder if the older tender just is not up to the task, or incompatible.

I will scroll thru that thread, Thanks

 

Does this pigtail have an in-line fuse like the Battery Tender pig tails? If so I'd check the fuse.

 

no fuse

 

good advice thanks

 

I recently had to restore/charge my battery from a completely drained state (they key was left in "on"), the voltage got so low (~3.0v), CAN-BUS was not waking up and connecting the charger just to the battery terminal did not work (Optimate prevents repairs on batteries when they connected to the wiring). I have disconnected battery wire from the positive terminal (under plastic cover) and started the repair/charging (the negative was attached to an aluminum bar which goes under the seat). It took almost 2 days, but now the battery is reported as healthy. In the ideal situation I would take the battery out, but was just monitoring the temperature by hand.