battery position advice

[handbaked]

Hi

So my ebike is getting dangerously close to being ready! But i have come up against one last big hurdle.

I am using a small jump bike frame as seen in the pic so it did not have bottle cage mounts. I fitted 3 rivnuts on the down tube for mounting. I knew it was going to be a tight fit regarding taking the battery on and off. Unfortunately it doesn't bloody fit!

So i have 3 extra holes in the frame i don't need (nevermind) but the question of where to mount the battery. The only real option is on the top tube as its a small frame i wonder how off that would be balance wise. i think i would need to push it bit closer towards the bars (half way along top tube) so that it didnt clash with my thighs.

Any other ideas? Other than get a new frame...

 

[D C]

Would there be clearance under the down tube?
Dave

 

[Deleted member 4366]

Did you trie inverting it ob the downtube so that the vontroller is at the top, which would give more clearance to lift the battery off its holder. It might look a bit wierd though.

 

[handbaked]

Would there be clearance under the down tube?
Dave

I was thinking this may work. But is it a solid enough bracket for upside down mounting?

 

[handbaked]

Did you trie inverting it ob the downtube so that the vontroller is at the top, which would give more clearance to lift the battery off its holder. It might look a bit wierd though.

Hmm. Not tried this. But not sure there is the head height for the battery at all. Will try this in next couple of days

 

[D C]

I was thinking this may work. But is it a solid enough bracket for upside down mounting?

Good point, maybe some good quality Velcro straps for extra support if you have clearance over the front wheel of course.
Might not be the best option regarding splash back and mud etc.
Dave.

 

[selrahc1992]

Hi

So my ebike is getting dangerously close to being ready! But i have come up against one last big hurdle.

I am using a small jump bike frame as seen in the pic so it did not have bottle cage mounts. I fitted 3 rivnuts on the down tube for mounting. I knew it was going to be a tight fit regarding taking the battery on and off. Unfortunately it doesn't bloody fit!

So i have 3 extra holes in the frame i don't need (nevermind) but the question of where to mount the battery. The only real option is on the top tube as its a small frame i wonder how off that would be balance wise. i think i would need to push it bit closer towards the bars (half way along top tube) so that it didnt clash with my thighs.

Any other ideas? Other than get a new frame...

My brompton always feel perfectly balanced when with front luggage and weight in front: crazy thought,but will a few rivnuts intrude too much into the head tube? If not could the battery mount vertically there,is there enough cable. I have same battery on oxydrive and she me how imagine vertically it will rattle led through potholes

 

[handbaked]

My brompton always feel perfectly balanced when with front luggage and weight in front: crazy thought,but will a few rivnuts intrude too much into the head tube? If not could the battery mount vertically there,is there enough cable. I have same battery on oxydrive and she me how imagine vertically it will rattle led through potholes

Maybe not such a crazy thought. It would even out the weight what with a rear wheel drive. And it wouldn't be mounted to bars or forks so steering would not physically be heavier.

I'm not bothered about adding extra rivnuts if needs be.

Hi

So my ebike is getting dangerously close to being ready! But i have come up against one last big hurdle.

I am using a small jump bike frame as seen in the pic so it did not have bottle cage mounts. I fitted 3 rivnuts on the down tube for mounting. I knew it was going to be a tight fit regarding taking the battery on and off. Unfortunately it doesn't bloody fit!

So i have 3 extra holes in the frame i don't need (nevermind) but the question of where to mount the battery. The only real option is on the top tube as its a small frame i wonder how off that would be balance wise. i think i would need to push it bit closer towards the bars (half way along top tube) so that it didnt clash with my thighs.

Any other ideas? Other than get a new frame...

 

[handbaked]

Ok so i have tried a couple of different things and are still stumped. ..

Unfortunately simply turning the battery around within the triangle as suggested does not work as there is not enough movement to clip it on and off.

There is also not enough vertical space between the bars and wheel to have it mounted on the head tube.

Which leaves me with just a handful of other options.

* on the cross bar, forward towards the bars - high centre of gravity, look a bit 'wrong'
* on a rear pannier - lots of weight to rear what with rear motor
* on a front pannier - heavy steering, look strange on this type of bike
* in a backpack - unwanted weight on back plus slightly more dangerous

If anyone is willing to put in their pennies worth it would be appreciated. The bike is now fully built and wired just waiting to mount and plug in the battery to test ride!

 

[Deleted member 4366]

A rear motor and battery on the rack works as long as you get rhe battery as close to the seatpost as possible and as close to the wheel as possible. It's not so good on a bike with rear suspension because of the extra height you need.

If it's a bottle battery that'll fit in the triangle, but you can't get the battery on/off its holder, you can use alternative fixing methods to mount it pemanently there. There's lots at the top that you can put a strap though and you can strap or U-clamp the bottom end.

 

[handbaked]

I guess i could go the permanent fixing method within the triangle but it just means i need to run a power cable to my shed to charge. I saw there was a strap point at one end but what kind of strap do you recommend? And what fixing are you referring to when you say a u clamp for the other end? Do you mean one long enough to go over the entire battery?

Cheers.

 

[Deleted member 4366]

Do you have the integrated controller or is the compartment empty?

 

[selrahc1992]

I guess i could go the permanent fixing method within the triangle but it just means i need to run a power cable to my shed to charge. I saw there was a strap point at one end but what kind of strap do you recommend? And what fixing are you referring to when you say a u clamp for the other end? Do you mean one long enough to go over the entire battery?

Cheers.

I had the same struggle with a diy build Raleigh twenty to mount battery. one very messy solution (my controller and battery are separate) that struck me like a bolt out of the blue is to simply stuff it in a carradice saddlebag. that way its removable, reasonably safe in accidents, need no mounting, near the COG. Not tidy but a solution.

 

[handbaked]

That's a possibility but going to be another £60+ by the looks of it. I'm thinking bolting it on more permanently may be the right thing to do...

 

[mfj197]

I use an Apidura Saddlepack to house the battery. I need to carry things for commuting (clothes, tools etc.) anyway so need a bit of luggage space. Looks like this when it's expanded right out, but it will get a lot smaller if you don't take much.

Michael

 

[handbaked]

I use an Apidura Saddlepack to house the battery. I need to carry things for commuting (clothes, tools etc.) anyway so need a bit of luggage space. Looks like this when it's expanded right out, but it will get a lot smaller if you don't take much.

Michael

Looks good but at £85 I'm going to have to find a (much) cheaper option.

 

[handbaked]

Well i have bought a couple of u clamps. Actually car exhaust clamps. I cant work out a way to clamp the battery solidly enough. I now dont mind if the battery is fixed in a more permanent fashion but cant work out a way to clamp it.

Does anyone have any suggestions? This last hurdle is doing my nut in.

 

[handbaked]

Do you have the integrated controller or is the compartment empty?

Not sure what you mean by this. My controller is separate in a small saddlebag...

 

[selrahc1992]

Well i have bought a couple of u clamps. Actually car exhaust clamps. I cant work out a way to clamp the battery solidly enough. I now dont mind if the battery is fixed in a more permanent fashion but cant work out a way to clamp it.

Does anyone have any suggestions? This last hurdle is doing my nut in.

i attached my oxygen lcd with an exhaust clamp - i discovered exhaust clamps are strangely brittle and don't like being bent or vibrated too much (it snaps), however, i then bravely/foolishly nonetheless enlarged one of the serrations on the clamps that it screws on and put a small flat-head bolt through before putting the clamp back around the handlebars. it forms a kind of crap, impromptu "rivboltW, so to speak - and so far (over several very shaky months over potholes) it's held. I wouldn't trust it to hold a battery's weight though - id go back to finding a way to rivnut it, somehow rivnuts never go loose

 

[handbaked]

Thanks for the insight. I dont fully understand what you were trying to explain but brittle and not like to be vibrated isnt what i want for holding on a 3.5kg battery!

The reason i cant rivnut is because the space for the battery in the central triangle of the frame is so tight. There is not enough room to be able to take the battery off of the battery holder that screws to the rivnuts. So there is no way of actually screwing it on. ...