My First Real Build

[416]

Hi all
I'm new to the whole forum thing, but I wanted to be part of the community to share my bike and battery builds and gain some more knowledge along the way, but overall I'm here to have fun!

So... Here goes....

I bought this bike in September 2020.
It was a Radrover 5.
It's gone though a few different iterations, but here's it final form. (Minus a fardriver 72680 coming soon!)

5000w QS 205
Sabvoton 72150
72v 50ah P42A Molicel pack ( I'll start on the pack in a few days)
At the moment I'm using a 60v 43ah 135a made from 2 72v UPP batteries that I was going to get rid of , but I tore them down instead and built this pack. It runs fine and sags about 7v max which is honestly not bad for what they were.

I haven't tested the bike out yet because I'm not taking this thing out in any wet weather anymore I'll be building a thrid bike for that.

I tried to make a "custom" mount for my rear brake caliper as the spacing between the mount and the rotor is mabey 10mm or so from the rotor. I wish I had known this before hand, but not a problem. I'm mister fix it.

I JB welded 2, 203mm brake adapters together and then used a third one to mount the brake caliper and it worked! It didn't bite the rotor as much as I wanted so I tried modifying the adapter the caliper sat on by cutting down the mounting points and that worked also , but I couldn't grind them down flat enough and when I put it back on the positioning was off and it broke

I welded it back together just waiting 24h for it to dry and I'll remount it in the original position.

I've been trying to download the PC app with absolutely no luck! My bro couldn't figure it out either and he's the "computer guy" SMH. I can't even install it because my PC tells me there's a virus detected. Even tried uninstalling Windows Defender and that didn't work.

I have my regen throttle installed and I want to use it!

Apparently you have to use the PC app to switch to the regen throttle.

I'll honestly NEVER buy another Sabvoton controller ever. I have a 7280 that I ran for over 2 years and I love that thing, but their customer service is bullshit.

I don't want to make my first post too long, so I'll end this one here.

I would love your thoughts and feedback and any constructive criticism is welcomed.

Thanks guys

 

[SlowCo]

Nice project but I hope you have two torque arms on the rear especially with the higher amp controller. Not sure how the brake caliper brackets are supposed to work and not fail with only JB weld? Please be careful...

 

[416]

Nice project but I hope you have two torque arms on the rear especially with the higher amp controller. Not sure how the brake caliper brackets are supposed to work and not fail with only JB weld? Please be careful...

Thanks for the response. I'll add another torque to each side. I'm going to see if I can get a mount 3d printed or better yet, get one CNC machined out of aluminum.

 

[Risky Rob]

I converted an old hardtail mountain bike, and installed a new suspension fork, with disc brake mounts for the front. The old frame was not set up for rear disc brakes, so I just installed center pull brakes in the rear. The bike stops fine.

 

[Apartunis]

I converted an old hardtail mountain bike, and installed a new suspension fork, with disc brake mounts for the front. The old frame was not set up for rear disc brakes, so I just installed center pull brakes in the rear. The bike stops fine.

Center pull? Do you mean cantilever brakes? 70s center pull calipers probably would not have the right length for a mountain bike and aren't very impressive at stopping.

Rear brakes do not need to be powerful if there is a front brake. Either the front brake takes weight and traction off the rear wheel, or there is a slippery surface that keeps you off the front brake and makes hard rear braking impossible.

 

[Risky Rob]

Center pull? Do you mean cantilever brakes? 70s center pull calipers probably would not have the right length for a mountain bike and aren't very impressive at stopping.

Rear brakes do not need to be powerful if there is a front brake. Either the front brake takes weight and traction off the rear wheel, or there is a slippery surface that keeps you off the front brake and makes hard rear braking impossible.

Center pull brakes offer better mechanical advantage and leverage, making them effective for stopping power, especially on bikes with wider tires. They also tend to provide more consistent performance and easier maintenance compared to side pull brakes, which can require precise alignment

 

[Apartunis]

Center pull brakes offer better mechanical advantage and leverage, making them effective for stopping power, especially on bikes with wider tires. They also tend to provide more consistent performance and easier maintenance compared to side pull brakes, which can require precise alignment

My question was are you talking about these brakes

or these brakes?

The first kind are cantilever brakes. The second kind are centerpull brakes.

 

[416]

I converted an old hardtail mountain bike, and installed a new suspension fork, with disc brake mounts for the front. The old frame was not set up for rear disc brakes, so I just installed center pull brakes in the rear. The bike stops fine.

Hey Rob.

That's a good idea, but I wouldn't feel too confident with that as my rear brake, but it might be worth a try if all else fails.

I'm pretty sure I can get something 3D printed or machined. I just need the correct specs.

Does anyone know of a good CAD program I can download to my laptop and use to create a 3D image?

 

[416]

Nice project but I hope you have two torque arms on the rear especially with the higher amp controller. Not sure how the brake caliper brackets are supposed to work and not fail with only JB weld? Please be careful...

Thanks again for the advice on the torque arms. I have 2 more sets arriving tomorrow. I'll have 3 on each side and they'll all tie into each other in a triangle formation. I'll post pics when it's done.

 

[Risky Rob]

Hey Rob.

That's a good idea, but I wouldn't feel too confident with that as my rear brake, but it might be worth a try if all else fails.

I'm pretty sure I can get something 3D printed or machined. I just need the correct specs.

Does anyone know of a good CAD program I can download to my laptop and use to create a 3D image?

Most braking is from the front, and up there I put a hydraulic disc brake, with a big rotor.

 

[Apartunis]

Most braking is from the front, and up there I put a hydraulic disc brake, with a big rotor.

I use a bigger rotor in front, between 22 and 25 inches. Thermally superior material too.

 

[gromike]

Regen can do a whole lot of the braking, that is if you have a DD motor.

 

[Hummina Shadeeba]

Fish paper between series groups and fish paper donuts on the positive is very worth doing. It looks like maybe fish paper donuts u added and then shrink wrap

 

[fill]

For basic cad and an easy in TINKERCAD.. when i dabbled in 3d printing a vid directed by 'dad' and presented by 2x pre teen kids launched me in less than 10 minutes.. it is basic and learning focused but so is the arduino ide and some well executed and elegant examples of code exist within the arduino ide and its example sketches..

 

[high voltage]

Hi i seen your battery build & wondering if you know anything about ant-bms its lock me & i don't know getting to charger again .i have low cell its about 2.300 -2.600 & i can't the bms to balance the low cell i don't get whats happening .can please help .

 

[high voltage]

Oh yeah its a 72volt 50ah i think ?

 

[Risky Rob]

Hi i seen your battery build & wondering if you know anything about ant-bms its lock me & i don't know getting to charger again .i have low cell its about 2.300 -2.600 & i can't the bms to balance the low cell i don't get whats happening .can please help .

I had a old, weak battery that wouldn't charge. I put it into the bike and discharged it a bit more, and then voila, it would then charge.
It never fully charged, but I used it for a few weeks for testing and short rides.

 

[Hummina Shadeeba]

Hi i seen your battery build & wondering if you know anything about ant-bms its lock me & i don't know getting to charger again .i have low cell its about 2.300 -2.600 & i can't the bms to balance the low cell i don't get whats happening .can please help .

Maybe u have to charge the low groups individually to get them above the threshold it will charge, maybe up to 2.5 or 3v, then it will charge. Maybe the bms only top balances the cells

 

[416]

Hi i seen your battery build & wondering if you know anything about ant-bms its lock me & i don't know getting to charger again .i have low cell its about 2.300 -2.600 & i can't the bms to balance the low cell i don't get whats happening .can please help .

Hey dude.

Try the link I've attached.

It's for the ANT BMS website. Tells you everything you'll ever need to know about thier BMS'.

I hope it helps

ANT BMS APP User Manual – Download – ANT BMS

antbms.vip