Want to mount downtube battery to rear rack...

[Tom@WashDC]

Ok. Please don't connect both batteries at the same time. Disconnect the one battery completely before you connect the other.

 

[rich c]

Those are pretty small connectors. I have those on one of my battery packs for charging. I used XT 90 connectors for the main current. Keep an eye on them for signs of melting.

 

[mohammed]

Ok. Please don't connect both batteries at the same time. Disconnect the one battery completely before you connect the other.

For sure! I'm unable to connrct both batteries anyway, the cables aren't long enough... this is the safety feature!

 

[mohammed]

Those are pretty small connectors. I have those on one of my battery packs for charging. I used XT 90 connectors for the main current. Keep an eye on them for signs of melting.

Thanks for the tip, will do! The battery actually came with XT60 but LBS asked to swap these out as they had the correct cables already (saved them from loads of soldering etc).

 

[6zfshdb]

Thanks for the tip, will do! The battery actually came with XT60 but LBS asked to swap these out as they had the correct cables already (saved them from loads of soldering etc).

Those Anderson Powerpole connectors are good for 45 amps. They are silver plated to avoid corrosion. I use them, as well as the XT60's and have had no problems with either.

In the past, I've used my batteries individually as well as wired in parallel with an isolator. When wired together, they both discharge at the same time and I have to recharge both every time I ride. Unless you make a rig that will charge both at once, you either need two chargers or remember to switch batteries on a single charger.

I stop frequently when I'm riding anyway, so swapping a battery connector is no big deal.

 

[tomjasz]

Those are pretty small connectors. I have those on one of my battery packs for charging. I used XT 90 connectors for the main current. Keep an eye on them for signs of melting.

They can be 45A rated. Counterfeit is the problem. NOT the physical size of the Anderson connectors.

he battery actually came with XT60 but LBS asked to swap these out as they had the correct cables already (saved them from loads of soldering etc).

I would be treating them with an anti-moisture, an anticorrosive product like Boeshield T6, shame the LBS doesn't use the Anderson accessories.

 

[tomjasz]

Something I seldom see discussed but with every Hailong case I've purchased included is these rubber gasket/bumpers. I use them between the base and the rack or rack adapter.

 

[mohammed]

Something I seldom see discussed but with every Hailong case I've purchased included is these rubber gasket/bumpers. I use them between the base and the rack or rack adapter.

I had these but the LBS didn't use them!

 

[mohammed]

They can be 45A rated. Counterfeit is the problem. NOT the physical size of the Anderson connectors.


I would be treating them with an anti-moisture, an anticorrosive product like Boeshield T6, shame the LBS doesn't use the Anderson accessories.

I've looking around for the weather resistant dust caps but can't seem to find anyone in the UK selling them, strange!

 

[6zfshdb]

I've looking around for the weather resistant dust caps but can't seem to find anyone in the UK selling them, strange!

Amazon uk has the black Anderson Powerpole covers:

https://www.amazon.co.uk/Treedix-Retardant-Compatible-2-Position-Connectors-Black/dp/B08FMKHR1N/ref=sr_1_1?crid=2SZT82NZEA53O&keywords=anderson+powerpole+covers&qid=1675687589&sprefix=anderson+powerpole+covers%2Caps%2C170&sr=8-1

 

[linklemming]

I've experimented with rack mounted batteries and found the battery weight mounted that high adversely affects bike handling due to the higher center of gravity.
I did just the opposite and moved the battery from the rear rack to a lower position on the down tube. This distributes the weight lower and farther forward which, in my case, greatly improves handling. I now carry my spare batteries in panniers which are lower to the ground and don't cause center of gravity issues.

Every bike & rider are different though, so try it and see how it works out.

E

I recently added a setup to one of my ebikes like in post#5.

Not only does it add weight high, it also adds weight way out on the end.

In the case of my BBSHD equipped Surly Ogre with Origin 8 Strongbow bars (which allow me to get aero), the bike gets pretty nasty headshake when doing anything over 20mph when in the aero positions. This would also be a factor if I took my hands off the bars. With my hand in the normal flat bar position, its no problem.

This behavior is "really bad" with a super shark on the downtube and a jumbo shark on the rear mount. Im surprised I didnt crash the first time it happened. While still present with the batteries swapped, its manageable.

 

[tomjasz]

the bike gets pretty nasty headshake when doing anything over 20mph

A function of geometry IME.

 

[6zfshdb]

I recently added a setup to one of my ebikes like in post#5.

Not only does it add weight high, it also adds weight way out on the end.

In the case of my BBSHD equipped Surly Ogre with Origin 8 Strongbow bars (which allow me to get aero), the bike gets pretty nasty headshake when doing anything over 20mph when in the aero positions. This would also be a factor if I took my hands off the bars. With my hand in the normal flat bar position, its no problem.

This behavior is "really bad" with a super shark on the downtube and a jumbo shark on the rear mount. Im surprised I didnt crash the first time it happened. While still present with the batteries swapped, its manageable.

As mentioned in other posts, lately I've been experimenting with using multiple cordless tool batteries which can be placed in various locations on the bike to improve weight distribution. Their smaller size and weight allows them to be carried in panniers, a rear rack bag, handlebar bag, mounted to a downtube or any combination. I use a fast jobsite charger that will recharge 4 batteries at once in 2 to 3 hours.

The only downside is the extra few minutes it takes to wire them up before a ride. Since the battery locations can vary, it's difficult to install permanent wiring.

I should also mention that many of these cordless tool batteries do not have a low voltage cutoff circuit in the BMS. Many brands put the LVC in the tool instead. Consequently, battery voltage must be monitored to prevent over discharging.

 

[Litebike]

What I did is similar to other mods seen here but with better placement for center of gravity. I put a 20ah triangle battery on my Rad Rover 5 and used a Topeak Uni Super Tourist DX rear rack to carry the oem battery. That rack is very adjustable to position it far forward and very low to the tire. With a little modification to the upper mounting straps I was able to get most of the battery weight in front of the rear axle and just above the rear tire. My mission was to keep the extra battery weight as low and forward as possible so I cut the Rad Rover plastic fender so that the rack acts as part of the fender to put the weight even lower. By bending the rack's tail light holder outward I was able to use it to bolt on the Rad fender tip. (I cut it too short for mud). The rack is designed to carry heavy loads and it has a slide on mounting system for Topeak DX bags. I made an adapter plate from pvc that screws onto the Rad oem battery cradle, so now the battery and cradle can just be slid on and off easily and quickly. By drilling a hole in the plate, the battery still locks to the cradle and can be removed from the cradle for charging or whatever. Sliding the assembly onto the rack with the battery facing backwards allowed me to use a short connector cable too. Dropping a 1/4" bolt into a hole in the forward side of the pvc plate keeps the assembly locked in place and if I put a nut on the bolt the battery is locked onto the rack but can still be removed from the cradle with the oem key lock. If I use the Topeak pack on the rack, the battery can either fit inside (tight fit) or in one of the fold out panniers. This system works perfect for me, and never having 'range anxiety' is well worth the extra battery weight and less than ideal mounting location. Once the bike is rolling I don't even notice the weight.

 

[ronaldrodgers]

Thank you for all your posts. The posts have assisted me on my project.