Build Thread: best bang for $1000

[vt-05]

Hi All,

i am about to embark on my first build, I have a relatively flat 20km round trip and want to build the fastest bike $1000 will afford (excluding bike).

I have done some reading around this but am keen to hear your kind input.

lastly i like simple - there will be nothing that does not need to be there

 

[dogman dan]

Cheap direct drive motor, 72v 40 amps controller, The rest of the budget, around $500-600, goes to the battery of your choice.

Usually the biggest size for the least price is the hobby RC lithium cobalt stuff. Leave some budget for a decent charger though.

As always, don't store or charge those lico packs in a place you wouldn't build a fire.

 

[Nobuo]

have You tried to put anything on that white bar on the upper right corner?

You should share some specs You want, as rim size, front, rear or mid drive, range, frame size, suspension, etc

 

[vt-05]

A few more details;
Rider 95kg, wheels 700, frame, lugged steel 65cms, single speed.

S
What voltage should I aim for? Any recommendations for a motor or controller?

 

[wesnewell]

http://endless-sphere.com/forums/viewtopic.php?f=3&t=66302

 

[markz]

yescomusa.com for ebike kit
hobbyking.com for batteries and charger

 

[neptronix]

Leafmotor 1500w kit plus lipos.
Learn what you're doing with lipos otherwise you'll burn your house down though.

hey.. you asked for cheap and fast.

 

[riba2233]

In EU the panasonic PF's are cheaper than 20C lipo. :lol: But there's an assembly of course.

 

[Nobuo]

A few more details;
Rider 95kg, wheels 700, frame, lugged steel 65cms, single speed.

S
What voltage should I aim for? Any recommendations for a motor or controller?

48V is your friend

 

[Nobuo]

In EU the panasonic PF's are cheaper than 20C lipo. :lol: But there's an assembly of course.

Thats worth for big packs, and some free time

 

[vt-05]

thanks for all your advice guys, so here is what i think i will need;

ZIPPY Flightmax 8000mAh 6S1P 30C - if i go for 4 - 89v will it fry or fly? - 91.5 * 4 = $366 - could it take 100v?
1500w leaf motor delivered - $313


please could someone recommend me a charger and a secure case i can bolt in (will probably weld brackets) or a frame bag to get me going

 

[friendly1uk]

You might want to stick to 72v. A higher voltage will give top speed, but your budget won't buy the battery to do your 20k. You can't ride it at half it's top speed to provide range, as efficiency will be poor. You need to build a bike to do the speed your going to do. If you want to do 50kmh you don't build a 75kmh bike. It will under perform at 50kmh.

I have no idea how fast you want to go. It sounds like a conversation down the pub. We are going nowhere.

Many people come here, build the fast bike they think they need, then realise 30kmh is all they do on it. Most of us in fact. Which makes the DD motor unsuitable. I run a 500w geared hub with a 500w controller and it makes 3 times the torque of a 1000w DD ebay motor on a 1000w controller. So I'm going up hills and embankments the DD can't climb, yet I have half the battery and the same range. However, I can manage maybe 45kmh while the DD can reach 55kmh. I have that v8 grunt, but the DD is a 1.6 turbo. At the pub the DD wins on top speed, but at the traffic lights the geared motor is away. The two cross over around 30kmh. Under which the 500w geared is better, and over which the DD is better.

You don't want to learn all this today, so tell us how fast you want to go. Be realistic. Consider how fast have you ever been on a bicycle. Don't get confused with motorcycles.

The pub-man mentality guides us towards 72v 40A which is all that 1000w motor can be expected to take. Perhaps too much. It's near 3000w. Excellent pub figures. Though I imagine my 500w setup would beat it off the lights, and can be pedaled easily. The motor weighs half. Batteries smaller. I wouldn't dream of a DD motor myself. They just don't have the torque. But then I rarely pass 40kph, because I'm not on a long deserted road. I'm an urban cyclist.

 

[dogman dan]

72v at 3000w will fry the cheap 28mm magnet hubmotors in about 10 miles of continuous wide open throttle. But you don't need that much distance. So you'd be fine with 72v. If you need longer distance, drop it to 2000w, or get a bigger motor.

100v requires a different, usually more expensive controller, and wider magnets in the motor. You'd get a totally different recommendation if you said you have 2-3 thou to spend. Big power means huge battery costs for any kind of long ride.

Also you'd get much different advice if you mentioned the word safe.

40 mph club on a thou doesn't change much, 72v 40 amps controller, cheap hobby batteries, cheaper bike with likely insufficient brakes, See ya in the emergency room. :lol: Save some of that budget for riding armor. Man, a skinny tire bike going 40mph is easy to lay down.

 

[spinningmagnets]

I like geared hubs for most recommendations, and theres a reason they are the most popular for 20-28 MPH. But...you mentioned fast and for anything over 30-MPH up to 40-MPH...geared hubs just can't take the heat and the peak-amps on the gear-teeth.

The Yescom kit is cheap, and Dogman has been doing this for a very long time. I agree with him, you'll need 72V to go very fast, and...as far as the heat in a DD hub when you are dogging it at 40-MPH? Get a hole-saw and a can of motor stator enamel. Pull the motor apart, spray it down for rust-proofing and water-resistance....drill ventilation holes into the side-plates to let the heat out (there's a thread on this)...and that's about as good as it gets for $1,000.

To go faster than that, you will need more money...to be more reliable, you will need more money.

 

[neptronix]

Stay away from the zippy brand. They are overrated and overspecced. Read up some more on the various forms of lipo before you buy anything.
Read my lipo tutorial in the battery section before you order. Read a few other lipo tutorials, too. Getting lipo from the start is what i did.. but let's be honest, it is kind of like buying a fully decked out AR-15 with no safety features as your first gun, or handing your kid a ferrari as their first car.

The leafmotor is cool because it's the most efficient DD hub in it's size range that you can buy right now. 7-10% more efficient than the yescom, and not too much more expensive. A great way to get cheap speed.

thanks for all your advice guys, so here is what i think i will need;

ZIPPY Flightmax 8000mAh 6S1P 30C - if i go for 4 - 89v will it fry or fly? - 91.5 * 4 = $366 - could it take 100v?
1500w leaf motor delivered - $313


please could someone recommend me a charger and a secure case i can bolt in (will probably weld brackets) or a frame bag to get me going

 

[vt-05]

as you guys like info i have attached the route including my elevation - 7.5km of bike trail - 5km on 90% straight 60kmh road - i have to arrive at 0630 so reduced riding time is more time in bed. IT CAN NOT GO TO FAST!!!

thinking about making this guy an offer as the suspension and disks may be good;
http://www.ebay.com.au/itm/261792826392?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

[vt-05]

hey neptronix what batteries are you powering the 1500w leaf motor setup with?

 

[1KW]

leafmotor 1500w also has 2x the torque…40mm stator?

 

[ebikedelight]

My cheap yescomusa/ xcessories motor will pull me around 36 mph on flat land ...with a 20ah/ 48 volt lifepo4..which weighs around 21 lbs..and I weigh around 230 lbs.

90% of the time, I stay around 16- 22 mph...so the top speed is barely used.

I think most people who get in this hobby, often concentrate to much on top speed and not enough on torque for going up inclines or capacity for travelling longer distances.

For me, the best of all worlds is a cheap setup like the yecomusa motor for $199 shipped and a matched battery/ controller that will allow a max top speed of 35- 40 mph but with solid torque/ power to go up some short 15-25 % inclines and longer 5-10% inclines and for riding some nice dirt trails . ...and the ability to do this, not only inexpensively, but reliably.

 

[ebikedelight]

So the general consensus for the 1000 watt yescomusa motors is using 72v - 40 amps battery/ controller, to get overall best speed/ torque out of that motor, without burning it up { as long as you dont run it wide open throttle for 15 miles or wide open throttle up a 2 mile incline of 25% slope } ?


Are the hobbyking multistar packs, still the cheapest , most reliable option in batterys to get that 72 volt- 40 amp capacity ?

My Lyen controller can only adjust the voltage to a max of 75 volts ....does this mean that I could not use a 72 volt lipo setup, since that setup would be way over 75 volts when fully charged ?

 

[Samd]

Skip the leaf. Let me ship you a mxus v2 and controller.
That'll rustle nep's jimmies.

 

[wesnewell]

So the general consensus for the 1000 watt yescomusa motors is using 72v - 40 amps battery/ controller, to get overall best speed/ torque out of that motor, without burning it up { as long as you dont run it wide open throttle for 15 miles or wide open throttle up a 2 mile incline of 25% slope } ?


Are the hobbyking multistar packs, still the cheapest , most reliable option in batterys to get that 72 volt- 40 amp capacity ?

My Lyen controller can only adjust the voltage to a max of 75 volts ....does this mean that I could not use a 72 volt lipo setup, since that setup would be way over 75 volts when fully charged ?

I've run my 4 year old yescomusa motor on 24s rc lipo for the last 33 months without burning it up on the same $35 shipped 40A 72V controller I've had on it for the last 45 months. I have no idea what you can run on your controller, but if it's rated for 72V, running 20s rc lipo on it shouldn't be a problem. The most reliable cheapest batteries are the 20C 5000mah 4s hardcase packs for ~$25 each. How far you can run it before burning it up I couldn't tell you since I haven't burn mine up yet, but I've never run it wot more than a couple of miles with 100V 24s Lipo. Since a bought a tach, I can tell you the no load speed is 870 rpm on 90V. How fast that will get you loaded depends on many factors. The fastest I've had it going downhill was 61.something mph. And that was just once. I have no intentions of doing it again anytime soon. It's just too fast on a bike, and I've gone 120mph on a motorcycle before.

 

[dogman dan]

Yes, sometimes you can over volt a 72v controller and nothing happens. Other times, stuff fries when you get above the recommended max voltage of 90v, (fully charged) 20s hobby packs charges to 84v.

40 mph on the bike trail? you are going to really piss off people. Then one fine day, the cops will be waiting for you. You will be going by pissing off people daily, on a set schedule. I just assumed you'd be on a road, trying to keep up with fast cars.

You'll be as easy to catch as the flu.

Just because you can do 40 mph, doesn't mean you have to ride that way. You might best cool it on the bike trail, if it's like the ones I commuted on. Full of people walking, they'll hate you enough for passing them at 10 mph.

 

[markz]

Hardcase Lipos from Hobbyking, I bought 18 in total, at somewhere around $21 each. Pretty decent price, you need to do some research on the charger, I think the dual channel iCharger is the way to go, way more money ($100+), but well worth it. I went with a rc charger from hobbyking iMax b8, it does a decent job. Parallel charge, and do read up on all the lipo threads, it is a dangerous breed of battery but its cheap.
If nothing else, go to em3ev or ebikes and buy a ready to go setup. Looking back on it now, I should have totally gone with what a just mentioned for batteries, but its a learning process and I am still building my ebike. I have never ridden one before, theres snow falling tonight, a good few inches for sure so I am in no real rush to get it done, I have just been eyeballing some nice places to go riding. And if you buy a motor, get it laced, I am having one hard time getting mine together, Im just procastinating, but I got it laced properly now and will true it up soon. I got the mxus 3000w motor for my first ebike ever and I look at it like a monster engine so for a big guy like me I think it will do.

 

[wesnewell]

I don't recall there being any BMS's for rc lipo over 4 years ago so I bought a 14s charger. If I didn't already have my charging system today, I'd probably buy a BMS for my pack, and a cheap 6s balance charger to check individual packs.
If a 72V controller with 100V caps and 100V fets burns up at 100V, it's defective. Simple as that. I charge my pack to 100.8V every time, and never had a problem on either of my cheap 72V controllers. And they are both 4 years old.