Hiding battery in airbox / Lithium batteries

Right, I have my bike fully stripped :eek1 and am ready to get it coated etc but one thing I want to investigate is hiding the battery. I hate the location of the stock battery especially when there are no side covers.

Boxermetal's under frame unit looks good but a little pricey when postage to the UK is considered so I've been thinking about other places to put the battery.

How about the airbox? I intend to use pod filters anyway as this will be a fair weather form over function machine.

The little lithium batteries seem ideal and should fit in there nicely and then the cabling can be routed through the holes left in the airbox.

Anyone see any problems with something like this?

http://www.ebay.co.uk/itm/Lithium-I...95?pt=UK_Motorcycle_Parts&hash=item337dd39347

If you are removing the airbox, then do put the battery there, longways Is best, otherwise with the airbox removed there is a big empty space that just emphasizes the spindly nature of the BMW frame.

Unless you have a short wheelbase bike, you will have to fit some sort of sidecovers, otherwise you will have again a big empty space that needs to be filled.

iMHo etc etc

I intend to keep the airbox to keep that engine shape. As you say, I think it looks weird without and I'm not keen on those bikes where the battery is just bolted in place of the airbox. I reckon that one of those lithium batteries should fit, I need to make a cardboard mock-up really.

if the battery fits, i don't see why there would be any problem hiding it in there if you're going pods. my concerns would be mounting it inside the airbox so it isn't loose, and then fabbing up some sort of cap for the stock airbox holes just for aesthetics...

I like this idea - I too think that the airheads look a little weird without something finishing off that airbox area.

I think the empty space looks elegant. In my rebuild, the battery is getting tucked up under the seat so the middle of the frame is see-through.

I would eliminate the airbox, but I've not come up with anything that doesn't look hacked together to replace the air filtration. I think I'll be keeping it in place. Pod filters just aren't suited to a bike made for actual traveling -- not the best solution for dust, rain and puddles.

What about something like this.

While in theory I like the idea, anytime someone eliminates the air box, I wonder what the loss of cooling does to the electrical components. How do the lithium batteries handle heat?

I like it !That looks pretty cool.
Is that set-up for sale yet ?

It is. 70-79 models and 80-95 models

You really don't want to load on a threaded section like that.
On top of that, they appear to be cut threads.

Here's some data

I don't understand?

confused

I dont get it either you could use a 6x1.0 to hold that small load and it would never fail. In fact most "ah-murican" vehicles only use a 1/4-20 or 6x1.0 with a shitty wedge to hold the battery in and it whieighs in at 35-40 lbs.

Oh teh noes someone cut some threads; that will snap off like a 13 year old fat ginger in a 25 cent peek-a-booth.

seriously man it is a very light static load held by larger than necessary, yet stylish, hardware.

ETA it looks like 6X1.0 after I re calibrated my eyes, which make no difference in what I said

Consider what happens when the bike accelerates and decelerates.

The battery's momentum is applied to the structure in the direction of that acceleration. You are side loading those threads, with the length of the shaft acting as a lever.

The cut threads are notch points that focus the force, and the base plate attachment gives the lever a fulcrum point.

It's a nicely made bit of kit but I don't like the way the batter looks sitting there really. If there was a fibreglass cover or something that hid the battery it would be perfect but I just don't fancy it much!

I will be ordering the choke pulls from you at some point though!

I am using a very small Shorai battery tucked under the seat (LFX14a1-BS12) It is small enough to fit in the air filter if you wanted to. I was concerned at first if it would crank the bike on cold mornings. I live in Minnesota. It has been a champ so far. Event on those cold 30 degree mornings

If what you described were even remotely true, rubber and woven hold-down straps would have to be magic.

The battery is in a pocket. There is a friction component keeping the battery located within that pocket. The ONLY thing the bolts have to do is keep downward pressure on the battery and it ain't going anywhere--same as straps.

Rocking the battery exerts a lifting force and only the tiniest of bending forces. Those bending loads are negligible until long after the battery has translated enough to leave the tray. It's not going anywhere.

My biggest worry in that installation would be engine vibration being transmitted directly into the dangling lead plates in the battery. That's a sure-fire way to destroy a battery.

Draw a simple force diagram of the design we are talking about. ANY side loading on those threads is a problem.

I agree with you. Some early BMW's were solid mounted batteries and some had very small rubber bumpers for the battery to rest on. Realize that people that are doing these sort of modifications are not riding the bikes 1000's of miles a week or a month so the chance of any of this becoming an issue is slim to none.

I hope the production model is made with a larger radius?
All corners of this aluminum plate are cracked. A good rule of thumb is to use a radius 3x aluminum thickness. At least for 6000 or 3000 T3 or T4.