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Frankenstein budget build, possible future electric conversion project..

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Discussion starter · #42 ·
Shawn0331 said:
This is awesome. I cant believe you followed through with the build, Good job!
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Me either haha, i didnt think this would be done/working until next year! Cheers!

rooster18 said:
Do you have links for the motor and controllers setups?
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do you mean the controller software or the "manual"? there isn't one for the motor (or not that ive seen) I had a lot of help from reading the threads on endless sphere forum which sped up the process a lot
 
Discussion starter · #45 ·
#48 ·
ioxide said:
No worries, you tempted to convert one? its so much fun I don't even care about the limited range its such a blast during those 10-15miles haha.

Some more big roosts from yesterday

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My best friend is looking into it for a mini bike. We race them fairly seriously (mostly drags, some pavement circle track), and we are big into RC crawlers. I showed him your build and he was flaming at the mouth trying to find what you used haha.
 
#49 ·
ioxide said:
No worries, you tempted to convert one? its so much fun I don't even care about the limited range its such a blast during those 10-15miles haha.

Some more big roosts from yesterday

Click to expand...
I'm trying to get rid of a few bikes and finish up my z50a build but this is next thing on my list once those are done. I realized the other day I may have the perfect chassis to do this conversion sitting in my backyard. I have a ttr125 chassis with kx100 suspension fabricated to fit.

I see you say you may be getting 10-15miles, what type of riding are you doing with that? I'm trying to figure out how many batteries I need to get an hour of riding under 50% throttle, mostly just cruising at at 25% running around on fairly flat property to get around doing maintenance
 
Discussion starter · #50 ·
rooster18 said:
My best friend is looking into it for a mini bike. We race them fairly seriously (mostly drags, some pavement circle track), and we are big into RC crawlers. I showed him your build and he was flaming at the mouth trying to find what you used haha.
Click to expand...
Haha thats great!, Id really love to see what you come up with if you do build one!

mr.skywalker said:
I'm trying to get rid of a few bikes and finish up my z50a build but this is next thing on my list once those are done. I realized the other day I may have the perfect chassis to do this conversion sitting in my backyard. I have a ttr125 chassis with kx100 suspension fabricated to fit.

I see you say you may be getting 10-15miles, what type of riding are you doing with that? I'm trying to figure out how many batteries I need to get an hour of riding under 50% throttle, mostly just cruising at at 25% running around on fairly flat property to get around doing maintenance
Click to expand...
That would be a sweet project! is it 14/17size wheels? whilst the 2000w motor which I have will pull that size bike easily the larger wheels equate to a higher gear ratio and so a larger rear sprocket may be needed, or a reduction drive unit if a sprocket isn't available.

I have only been measuring my range by gps tracker and as I don't have a cycle analyst on my bike i'm not entirely sure how many watt hour miles im getting, and when I ride its a complete mixed bag of cruising, fast bursts, etc I try not to maintain high speeds if im actually going somewhere I just cruise slowly at 15mph or less,.

my battery pack currently is around 1340wh and as a rough estimate being as efficient as i can at 10-15mph id be getting 50-60 wh mile which could be 20-25 mile range, but being on loose dirt with small wheels and mx tyres saps a lot of power, and being trigger happy like me I get much less.

Some examples..

The alta redshift mx bike has a 5800wh pack so is roughly 4.3x the capacity what I have on my bike
Alta claims a range of 60 miles for city riding at 20-30mph on paved roads and 34 miles or 4 hours of run time on probably very twisty tight slow trails.

The Sur Ron light bee has a 1920wh battery pack and they also claim 60 miles range which is probably with road treads super high psi no wind perfect surface and a very lightweight rider etc etc but in reality most people get 10-15 mile range on that too..
 
Discussion starter · #52 ·
dirtbkr188 said:
Two questions that I have for you... 1. Do you have to run the batteries down to nothing before you can recharge them? 2. How long is a typical recharging time?
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Good question as lipo batteries can be funny and do require looking after.

each individual cell fully charged is 4.2 volts and fully discharged is 3.7v, lipo batteries start to get damaged very badly once the voltage goes below 3.6-3.7v and when i ride i actually stop at 3.8v, also if you only charge to 4.1v instead of 4.2v you can massively improve the cycle life (amount of full charges) of the battery.

You don't need to fully discharge before recharging though and its actually better for the battery if you don't fully discharge it, its also bad for the battery to leave it fully charged for long periods of time eg 24+ hours and a storage voltage of 3.8v is better.

I recently got a new charger which will charge my batteries from flat 3.7v to 4.2v in 2 hours.

My charger can put out 30A continuous charging current and my batteries (in parallel on the charger are a total of 60Ah) so it would half charge it in 1 hour or fully charge in 2.


with a 60a charger it would charge in 1 hour but then the charger is becomes quite expensive $200+ and whilst the battery can handle being charged this fast, again it degrades the batteries life span more.


Lipo chemistry is pretty volatile and does require some safety knowledge and research as people have had their houses burnt down!
 
#53 · (Edited)
ioxide said:
Haha thats great!, Id really love to see what you come up with if you do build one!



That would be a sweet project! is it 14/17size wheels? whilst the 2000w motor which I have will pull that size bike easily the larger wheels equate to a higher gear ratio and so a larger rear sprocket may be needed, or a reduction drive unit if a sprocket isn't available.

I have only been measuring my range by gps tracker and as I don't have a cycle analyst on my bike i'm not entirely sure how many watt hour miles im getting, and when I ride its a complete mixed bag of cruising, fast bursts, etc I try not to maintain high speeds if im actually going somewhere I just cruise slowly at 15mph or less,.

my battery pack currently is around 1340wh and as a rough estimate being as efficient as i can at 10-15mph id be getting 50-60 wh mile which could be 20-25 mile range, but being on loose dirt with small wheels and mx tyres saps a lot of power, and being trigger happy like me I get much less.

Some examples..

The alta redshift mx bike has a 5800wh pack so is roughly 4.3x the capacity what I have on my bike
Alta claims a range of 60 miles for city riding at 20-30mph on paved roads and 34 miles or 4 hours of run time on probably very twisty tight slow trails.

The Sur Ron light bee has a 1920wh battery pack and they also claim 60 miles range which is probably with road treads super high psi no wind perfect surface and a very lightweight rider etc etc but in reality most people get 10-15 mile range on that too..
Click to expand...
Actually mine is 19/16 so it would be just a step below a full size bike which to me is perfect for trail work and not so small its bouncing everywhere on rough trails. Yea I know Id have to gear it down alot to get the speeds right unless I wanted to have a top speed of 100mph lol

Good info, so it sounds like you battery setup should have enough for what I'm planning based on the limited data. I could always upgrade later if needed. Thats what my rough calcs said when I tried figuring it out just wanted to see if it translated to real world numbers. if there is room in my larger chassis maybe I can look into doubling up on batteries to get that longer run time if i need to do actual trail rides with a group
 
#54 ·
ioxide said:
Good question as lipo batteries can be funny and do require looking after.

each individual cell fully charged is 4.2 volts and fully discharged is 3.7v, lipo batteries start to get damaged very badly once the voltage goes below 3.6-3.7v and when i ride i actually stop at 3.8v, also if you only charge to 4.1v instead of 4.2v you can massively improve the cycle life (amount of full charges) of the battery.

You don't need to fully discharge before recharging though and its actually better for the battery if you don't fully discharge it, its also bad for the battery to leave it fully charged for long periods of time eg 24+ hours and a storage voltage of 3.8v is better.

I recently got a new charger which will charge my batteries from flat 3.7v to 4.2v in 2 hours.

My charger can put out 30A continuous charging current and my batteries (in parallel on the charger are a total of 60Ah) so it would half charge it in 1 hour or fully charge in 2.


with a 60a charger it would charge in 1 hour but then the charger is becomes quite expensive $200+ and whilst the battery can handle being charged this fast, again it degrades the batteries life span more.


Lipo chemistry is pretty volatile and does require some safety knowledge and research as people have had their houses burnt down!
Click to expand...
Yep Ive done a bit of pass time study for EV and phones and the 80/20 rule is definitely the best way to go to fight battery degradation. For those who dont know, its charge to max of 80% and recharge at 20% whenever possible. Obviously you can do higher charges and run down if you need the range but it comes at a cost of reduced battery life cycles
 
Discussion starter · #55 ·
mr.skywalker said:
Actually mine is 19/16 so it would be just a step below a full size bike which to me is perfect for trail work and not so small its bouncing everywhere on rough trails. Yea I know Id have to gear it down alot to get the speeds right unless I wanted to have a top speed of 100mph lol

Good info, so it sounds like you battery setup should have enough for what I'm planning based on the limited data. I could always upgrade later if needed. Thats what my rough calcs said when I tried figuring it out just wanted to see if it translated to real world numbers. if there is room in my larger chassis maybe I can look into doubling up on batteries to get that longer run time if i need to do actual trail rides with a group
Click to expand...
on the endless sphere forum there is a guy who converts full size mx bikes called SilentEnduro, he uses the slightly larger 3000w 138 70h motor but also makes a reduction drive and seems to make some great conversions he does have youtube videos also.

I'd say for your size bike double the capacity that I have would be a good start, im sure you have way more room than I do, if you plan it smart you could even have one lightweight pack for a nimble bike and a larger one for long range.

One trouble is if you buy some batteries and then later you want to add more in parallel for extra capacity its not always safe as the first set of cells have already been used and don't often keep in balance with the newer cells, just to bear in mind its better to buy all the cells at once and use them all at the same time and recharge all at the same time etc

I'd also recommend at least looking/researching into 18650 and other battery packs just to help understand the pros and cons of the different types of batteries as you never know it may suit your needs better than the rc lipo packs im using.
 
Discussion starter · #59 ·
mr.skywalker said:
Ok yea those 18650 look great as an option for custom shape building to keep fitment easier and they are fairly cheap. I think that may be my method.
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yeah definitely better for specific shapes, but a bit more complicated when spot welding all the cells together, 18650s will often have a higher energy density but often cannot deliver sustained peak amps like lipos can

tmas said:
What happens if you get the QS MOTOR 120 2000W motor wet or muddy? Will it just wash off or will water destroy it?
tmas
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I have only hosed and scrubbed it down a couple of times but and no issues yet ? , on aliexpress it says the motor is ip54 rated so it should be fine to wash down but i wouldn't pressure wash it, the controller surprisingly is ip67 but I wouldn't pressure wash that either..
 
#60 ·
ioxide said:
yeah definitely better for specific shapes, but a bit more complicated when spot welding all the cells together, 18650s will often have a higher energy density but often cannot deliver sustained peak amps like lipos can
Click to expand...
Yea I watched a few ways to build the cells but there are expandable kits available that avoid the whole spot welding so it like legos essentially(but comes at a higher cost but builds a very nice clean cell with great connections and much easier to assemble). I'll have to look into that aspect of the sustained amps. i guess on the electric bicycle where 18650s are often used dont have high requirements for the higher sustained peak amps but then again what I use it for, will mostly be just putting around and on tight single track, rarely has high sustained draw other than occasional longer hill climbs so might be ok
 
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