Lithium Ion battery install
This is a quick DIY for installing a Shorai Lithium Ion battery into the Ninja 400. The battery I installed is the LFX14A4-BS12. This is the recommended replacement for the Ninja 300 according to Shorai. It has the following specs:
12 V
210 CCA- Cold Cranking Amps
14 Ah- Amp Hours
60 Wh- Watt Hours
Weight: 1.98 lbs/0.901 kg
Case Size 4: 86mm/3.39" x 148mm/5.83" x 88mm/3.46"
The stock lead acid battery has similar dimensions, but obviously is a good deal heavier. I believe it is also rated for only 130 CCA and I recall it has 8 Ah capacity. For this reason a Shorai LFX12A1-BS12 with 155 CCA and 12Ah should be sufficient for the bike and will save ~.4 lbs. I opted for the marginally heavier LFX14 since I can swap it over to a larger bike at a later date if I so desire. It will also be more likely to turn over the bike in colder weather. Some of these lithium ion batteries have had issues starting in temps below 30-40F. I'm in a warm climate so that's not really an issue for me, but it is something I keep in mind if my wife or I rides the bike in a colder environment. In that case, the battery will need to be put under load to warm it up prior to starting, see here for more details:
Shorai LFX21A6 Battery in cold weather | Adventure Rider
Before I get to the install, I'd like to say this to the individuals who gravitate away from working on their own bikes: I'm a strong believer in DIY work, since it is liberating to understand the operation and intricacies of your motorcycle, having the satisfaction of accomplishment of a job well done, and achieving that visceral man/machine connection. Instead of dropping your bike at the dealer, I'd recommend getting a small quality set of hand tools and doing the simple maintenance tasks and modifications yourself. You'll learn a good bit, save some cash, and hopefully enjoy the heck out of it. The worst thing that can happen is you break something. Then you fix it and move on with life. I'll be posting a few more simple guides as I get some more parts, most of which are from the Ninja 300. There will be some retrofitting, but that's what makes it fun!
With that said, here's a quick guide on installing the battery.
1. First, pull off the passenger seat. Don't have pics of this, but the process is in your owners manual and involves putting your key into the lock on the left hand side of your bike and pulling the seat towards the gas tank while you twist the key. The fit of my seat is quite tight so I have to be careful when removing.
2. Next, remove the rider's seat. This is easily done by pulling on the small black loop that is located in the compartment on the right side of where the passenger seat used to be. A click should be heard and the seat can lift away.
3. You should now be looking at the battery, which is retained by a piece of bent sheet metal with a fastener. Remove the fastener and sheet metal retainer, and disconnect the terminals, negative first, followed by positive. The reason to disconnect negative first is due to the fact that a bike's chassis is typically grounded. Therefore, the potential between the negative terminal and the bike is 0V, so current will not flow if you "short" the wrench between the negative terminal and the chassis. Disconnecting the positive terminal and accidentally touching any bare metal on the chassis with the wrench has a 12V potential with virtually no resistance, which can weld your wrench to the bike due to the overwhelming current flow. While the odds of this happening are low, better safe than sorry. You should now be looking at the following, although the battery will still be stock in your case:
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4. Carefully remove the stock battery, and tape up the terminals. Store in a safe place, or sell it for $$$. Turn your attention to the sheet metal retainer, which has a rubber nub that lightly preloads the battery to prevent it from moving up and down during riding. Pull the nub out and put it back the opposite way so it looks like below. You can use a small screw driver to coerce the rubber plug through the hole, since it's a pain to push through. The Shorai battery isn't as tall as the stock battery, so this allows you to retain the battery without adding any foam or shims.
5. The positive battery terminal has bends which fit over the stock battery terminal. These will not fit over the Shorai, so grab a pair of pliers or vice grips to straighten them out. You only need to straighten the two on the left and right; the one directly across from the cable clamp doesn't need to be messed with.
6. Drop the new battery in, being careful not to touch the terminals to any metal. Connect the positive terminal first, followed by ground LAST. Install the sheet metal retainer as shown. Because I flipped the retainer over, I installed a slightly longer screw to get proper thread engagement, although the old screw would probably work just fine. Make sure to put the boot over the positive terminal when finished.
7. Put the key in, make sure the gauges come on and start the bike. Shorai claims their batteries ship with ~70% charge, so you shouldn't have to charge prior to starting. I let the bike idle for a bit while I cleaned up my garage to give the alternator a chance to charge the battery. Re-install the seats and you are good to go!
