new eMTB rider with battery question/s

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silverback

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Hi all, Toronto rider here. I brought along a few questions if thats okay. Battery related.

I built this ground up Stumpjumper 2014, they only did this frame version once. I like it better, my sitting posture is almost exactly as my CR500 when i raise the seat a1" or so. The bike a hella ridable but efficiency sux with that frame. It beat me up on a few longer rides. But its really comfortable. I pulled a major mullet , the hub with the motor is only a 26 inch. The factory stock front wheel is 29 and frame is L. I will drop it down to a 27.5 w/thru axle once I get the new Marzocchi forks sorted out. I rode 29er for a year then to experiment I played with wheel sizes. I went all the way down to 26ers. Wow. Even with the large frame it was too much. But I could flic around the bike like nobodies business. I think a 27.5 up front will be prrrrfect. I got this bike a year and a half ago, It still has needs but for now its a sweet rider. And now I get to work fast than my buddy in his car, at least half the time. If you name your bike I'm naming mine silverback. Like my other wheels all turn out silver/black for some reason =)
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I'll find a before image before I post a complete bike. I also don't have one here atm. Thanks for stopping in.
 
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She hasn't had a full clean in a while. For the frame cleaning I use a 3m pad and it really blings. For now too busy riding it. New forks headset and rim will make it perfect (to me). Wet Shimano single pistons will get bigger discs. As is the bike stops on a dime. Hope discs look cooler. And stop on a dime. Thanks for dropping in.

I might upgrade motor and controller, will see. It has a 500w 36v on it for now, which already gets along decent at 36. My main concern and question is the battery. I want to double capacity to 20 AH but I can only see them in 48 volts. I don't know if thats alright or not. Can it damage anything?

I'm brand new to e-power this is my first ebike. I just finished installing all the motor components after the bike was built. Recently this past summer.

Its time to get on it. I ride a lot through the day/night cause I like it. But its starting to get cold here man, especially at 6 am.
 
Can you tell me, what rear motor kit is that and how much voltage? It seems to sit well in your frame without becoming too bulky. What are your bikes rear dropouts width ?
 
The dropouts are 5.75 inches inside, motor is 350w and its a 36 volt system. the battery is on the smaller side ( 13 ah ) I would like to change it to 20 ah if I can find a compatible battery that fits in the same position. Part of my goal is to keep things as clutter free as possible. I'm still going to bury the derailleur cable inside the down tube and fit the others in a single wire loom. I just havent gotten to it yet. A full Surron twist throttle is on the list with the rest. They feel natural plus I can use both odi grips. I got a bud to cut the vinyl. Even though its not model correct I think it looks good anyway.

My question would a battery for a 48 volt kit be compatible and safe etc? The trouble with a smaller 350w I'm having trouble finding a battery with more capacity. I could use 4x what I have but even close to double ( 18-20 amp hours) would be a big help. I dont have tome to recharge 3 or 4 times a day.

I guess I could install a back rack to carry a second battery but I'm not thrilled with that option.

Annie, I forgot to mention my frame is a large. Every bit helps with tucking parts in cleanly. I think a larger rectangular shape batter will fit in there great. If I manage to get one with the specs I need. Its a Bafang 350w. A local store is selling the same model loose for 100 bucks and 150 laced in 26" wheel. Brand new. I'm debating weather to pick up a spare just in case.

Side question: How many kms will they go on the average? Under "normal" riding conditions through all four seasons.

thanks
 

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You could add a bottle battery with or without a blender. It would plug into the batteries "water bottle cage" and I would think you would have plenty of range. You could put the cage behind your seat.This one has Samsung cells. Aliexpress has a coupon at the beginning of each month. I have 20 amp hr 48v battery on my Kona and I wish I didn't. It is a ton of weight and I never use it all up. I wouldn't put 48v battery on a 36v system. Fully charged it is 54.6v, that is way too much for your setup.

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These might work for me. I'd prefer 1 larger battery if its doable. Maybe I can get someone local to build one for me, if the extra expense remains feasible?
 
I don't understand why it says this battery is compatible https://www.amazon.ca/dp/B0DHCTNKZ5?ref=emc_s_m_5_i_atc&th=1

It states the following..

Parameter : This 48V 20Ah e-bike battery (Sam-*sung Cells) is compatible with mid motors and hub motors ranging from 50W to 1500W , including 1500W , 1200W , 1000W , 750W and 500W models.

50w to 1500w. They make it sound like it will work with my 350w. Or is it more dependent on what controller I have?

Its confusing. All I want is a large capacity battery =(

I also seen something called a "step down converter" Would something like that or similar to that let me safely run more battery volts? I know with AC step down converters, they allow you to operate a 120 volt appliance with a 220 volt AC source, Thats where the confusion started.

It seems over complicated all I want to do it travel further, dam**t.
 
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Whyat is the bottom line mate?
You just want to have More saddle time/Ride time? Like you want to get on your ebike and ride farther than you do now?
You can add another battery top tube on your ebike up there.

Don't complicate it just do it ;)

You use amazon eh? so amazon search for a dual battery discharge balancer and another 36v battery.
If you want to go up to 48 volts you'll have to have BOTH batteries at 48v. so you'll need to change some settings or even the controller and display if need be.

Ya wanna travel farther eh? Dual battery that ebike ya have there and do it at 48/52v 35ah and you'll go really farther ;)
The man below can help with details if need be :)
(860) 951-1468
nebattsys@gmail.com
You'll wanna speak with Kevin and tell him HumanPerson from here sent you ;)
 
well, what i would do if it were my kit on that bike, i'd just over volt the system and see what it does while i wait for another kit
@48v :)
 
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HP, it's only 36 volts. If you tow a goldfish with a jetski, the little fishy's fins will fly off. On top of that, Canada has set counter tariffs into place from the US, so a battery built by Kevin will cost 25% more. He's better off with UPP or any other Chinese battery, as it won't be tariffed and I'm sure you've seen the wires coming out of a 36 volt controller, a warm bowl of soup would melt them. I'm going on the record as saying 48 volts is a bad idea. I just reread things and I guess you are suggesting he change out everything. My brain isn't working today. Still he might as well build a whole new ebike. :shrug:
 
Thanks fella's. I guess I don't need the bike to go faster, just further. It would also be nice to maintain the crisp throttle response longer as when the battery is fully freshly charged.

Its my first go at e power. it went pretty good I think. I decided to hold off changing the current kit and leaving it as is for now. And upgrade to a bigger kit, by bigger I mean 3-4 x the size.

I prefer not adding a second battery for a few reasons. It clutters up the bike too much and adds weight. Plus its a would be even closer to frank and beans if it ever went catastrophic. Stranger things have happened. The battery on the down tube is already kinda' close for comfort.
 
silverback said:
Thanks fella's. I guess I don't need the bike to go faster, just further. It would also be nice to maintain the crisp throttle response longer as when the battery is fully freshly charged.

Its my first go at e power. it went pretty good I think. I decided to hold off changing the current kit and leaving it as is for now. And upgrade to a bigger kit, by bigger I mean 3-4 x the size.

I prefer not adding a second battery for a few reasons. It clutters up the bike too much and adds weight. Plus its a would be even closer to frank and beans if it ever went catastrophic. Stranger things have happened. The battery on the down tube is already kinda' close for comfort.
Click to expand...

Most all bike / battery fires are caused by HIGH POWER not 350 500 750 or 1000 watts. Most of the rest were just poorly made with bad connections.....................
 
Good to know. And I see how some ppl cobble things together. Those type of mechanics arent allowed round my stuff. Like I was saying, stranger things happen. Still good to know.

I have $1300 CAD to find the best kit I can, 750-1000 watt. I might have enough left for my 27.5 wheels while Im at it. I found a local bro thats pretty good to me with open box parts. He may even be able to get me a kit and I won't have to screw with shipping at all. When I do I buy direct from Asia.

P.S tarifs be damned. I stopped ordering anything from down south. It hasn't slowed my hobbies down a bit.
 

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