Noob needs help upgrading bike

[mike662]

Hi everyone! So I built my first ebike a little over a year ago and I want more speed out of it now. Right now I'm running a rear 1000W 48V 26" Golden Motor hub with the standard GM cruise controller and their 48V 12ah lithium battery. I have done a lot of reading and I still have a few questions. First off, what controller should I get? I would like to go at least 60-70 km/h top speed, so what voltage will I require? And what batteries would be best to get? I see a lot of people getting li-po's but it seems to me like they are very difficult to take care of. Would it be possible to just buy another GM 48V battery and wire it in series to up the voltage to 96V? And I hear a lot of talk about FET's and stuff in controllers and adding them in and taking them out to get more/less power. What is so important about the amount and type of them?

I know this is a lot of q's but I really, really appreciate any and all help. My goal was to get a motorcycle but I decided to up the speed on my bike instead and buy all the motorcycle safety gear anyway. Range is not much of an issue to me, I mostly just need to commute 5 kilometers each way as fast as possible (lots of traffic where I live, it takes almost 10 minutes a kilometer, no joke), although I would like to go further on occasional rides, but that's just a want and not a need.

Here are some pics of the bike:

This is how the bike looks with the battery on

Here I have no battery on the rack but I included it to show that I put the controller in a bag on the front of the frame.

Mike

 

[mvly]

Wow nice clean build. I see a chain lock. Do you actually lock this up?

To answer your question. 60-70KM/h = 43mph (I am only counting the higher speed). Sorry I am in US so I will use mph instead of kmph.
I am assuming this speed desired is on flats and NOT climbing hills

Here are a couple of options from my experience and reading a lot of post on ES

a) Up the voltage on your GM. I hear people have gotten 40+mph using 72V on GM. It would be even better if you go 96V. But definitely check the limits of your controller. However you can always get a Lyen's controller (PM him) and I am sure he will sell you a decent controller that can handle up to 100V.
Summary: Get Lyen's controller for higher voltage OR check if your controller can handle 96V. Get another 48V12Ah and put in series and you are set. Make sure you charge them separately. Keep current limit low for testing and then up it until you get desired speed.

b) Get a new hub motor. This path might be more expensive since you have to get a new wheel and probably a new controller set since the new motor might not be compatible with all your current parts. For example, I have a BMC V3 motor with 48V50A controller and 48V30Ah battery and I can hit 40mph easy with current limit set to 35A. However sustaining this might be a problem and I have to wait carefully heat dissipated as heat vs kinetic energy. However there are other hub motors like HS35x or the x5 Crystalyte that MIGHT get you the speed you want with less heat problem at the same battery configuration.
Summary: Get a new hub motor and probably a new controller set. Mount everything and use your current battery. Make sure you get controller that can push 30A+ and you should be able to get 40+mph depending on your weight. : ) Just know that it's better to push more voltage vs more current. I only suggest this if you DO NOT want to get another battery. If your battery CANNOT handle the high current, you might be better off with a).

Good luck on the mod and be smart/safe on your 40+mph ride.

 

[wesnewell]

Buy this controller and 24s lipo pack. Charge to 100V. hang on when you hit the throttle.

http://www.dhgate.com/72v-1500w-brushless-speed-controller-for/p-ff808081283845f5012848d41bf455fb.html

Oh, don't try and series 2 48V packs in series. That'll end up around 120V. At least not unless you buy a controller that will handle that kind of voltage.

 

[amberwolf]

I would like to go at least 60-70 km/h top speed

Before doing any other upgrades to go faster, the first one I'd start with is the one to help you stop when you have to and thus: get good modulatable disc brakes at least in the front. Your fork already has the mounts for the caliper, though I don't know if your hub has the mounts for the rotor. If not, you'd have to replace the hub and spokes, relacing the wheel, or just replace the whole front wheel.

Next, I'd recommend replacing the bike rims and tires with moped or motorcycle rims and tires, so they will survive any poor road conditions/etc. at the speeds you're talking about. (37-44MPH)

Next, I'd make sure your suspension can handle the road conditions at those speeds. If you have all smooth roads with no debris and no potholes/etc, it won't matter, but it makes a huge difference hitting a 1" deep pothole or chunk of asphalt/etc. at 20MPH and 40MPH. At one it's just annoying if the suspension bottoms out or doesn't respond fast enough, at the other it could cause loss of control and a crash.


Just a side question: What causes it to take so much time per km? If it is time waiting for other traffic to be out of the way, or waiting at traffic controls, then having a faster bike isn't really going to change things much, if at all.

If it is time actually riding, then it seems like the bike you have is already fast enough to do the whole 5km in not much more than 10min., if that.

 

[dogman dan]

What is your top speed now?

You shoud be able to see at least 55-60 kph with a 1500 watt controller like the one mentioned above. At 1500 watts, it's pretty low amps so you should be able to stack a 24v battery with your current one and get away with it. I see nothing wrong with upgrading your bike to 72v with a low amp controller. That might get you into 55 kph. ( about 35 mph)

Since wind resistance is exponential, the speed you can reach with 1500 w is limited regardless of the voltage you run. You are going to need about 100v and 40 amps of that to be going 60-70 kph. 40 amps will quickly murdrer your existing battery. So get ready to spend some $$$$$. You'll need a hot controlller in the 90-120v range, high discharge rate batteries up to the task, and some really great torque plates to keep the wheel from just ripping itself right out of the dropouts with 5 hp of torque. Then to stop you will need some good disk brakes at least for the front wheel.

Since you are riding in traffic going 6kph? I'm confused what you need such speed for.

I can't recomend this highly enough, leave your existing bike alone, and start over with the best possible bike. That one is not suitable for over 55 kph. Then a motor possibly mounted on a motorcycle rim so you can upgrade tires to stuff designed for those speeds, motorcycle brakes, etc. Up to 55 kph, you can fudge it and use normal bike stuff, but having had a bike that did 70 kph I can tell you it was scketchy as hell. You can wear out tires from the heat alone cooking the cord apart in very few miles. Forget being safe trying to stop with rim brakes at that speed. I was riding this bike on a race track, or parking lots. So no cars. With cars, you need good tires, good brakes etc to go much faster than 55kph safely.

 

[mike662]

Thanks for the replies everyone! I currently can not invest in a more quality bike so it looks like I will just not go as fast for now.

Wow nice clean build. I see a chain lock. Do you actually lock this up?

When I built my ebike I was going for stealth. If I had known more about battery technology at the time I would have invested in some Lipo's to make it even stealthier. I lock my bike up all the time. It's an On Guard chain and the guy who sold it to me at the store (around $48 with tax) said you need a hydraulic cutter to get through it, so that's good enough for me

It would be even better if you go 96V. But definitely check the limits of your controller. However you can always get a Lyen's controller (PM him) and I am sure he will sell you a decent controller that can handle up to 100V.

Apparantly the 48V GM controllers can't go past 60V so I will definitely be replacing the controller. I hear good things about the Lyen controllers. What advantage would I have with going with this controller vs. the one that wesnewell posted:

Buy this controller and 24s lipo pack. Charge to 100V. hang on when you hit the throttle.

http://www.dhgate.com/72v-1500w-brushless-speed-controller-for/p-ff808081283845f5012848d41bf455fb.html

I like the thought of buying this controller as it is inexpensive, but can someone give me reasons as to why the Lyen might be a better investment?

Next, I'd make sure your suspension can handle the road conditions at those speeds. If you have all smooth roads with no debris and no potholes/etc, it won't matter, but it makes a huge difference hitting a 1" deep pothole or chunk of asphalt/etc. at 20MPH and 40MPH. At one it's just annoying if the suspension bottoms out or doesn't respond fast enough, at the other it could cause loss of control and a crash.


Just a side question: What causes it to take so much time per km? If it is time waiting for other traffic to be out of the way, or waiting at traffic controls, then having a faster bike isn't really going to change things much, if at all.

If it is time actually riding, then it seems like the bike you have is already fast enough to do the whole 5km in not much more than 10min., if that.

The roads I take are actually quite smooth and I travel them enough to know exactly where any holes are, so the suspension problem would not be too much of an issue. If I go anywhere else then I just wouldn't travel as fast. As for why it takes so much time per km, it's because the main road that goes from my house connects many major highways here as well as major streets, all within a few km of each other. Add to that the fact that I live in Canada's technology capital where there are lots of business buildings open all the time and the fact that there is major construction being done blocking off 1 lane in each direction for the next 4 years, traffic almost comes to a halt. I actually walked down the sidewalk here once along the road and stayed with traffic for almost 2 kilometers, until I passed the area where the highway entrance is. I usually take side roads to get to where I need so that increases my distance to travel and I need a good top speed to make up for the lost time. Also, sometimes I just need to take the busy road and the speed limit is 70 (60 now since it's under construction) and keeping up with the traffic would be a lot safer in my opinion as the drivers are very inattentive on this road. But even when it's packed full of traffic, I can easily zip by in the far right lane since there is a lot of space between the curb and cars there

What is your top speed now?

About 45km/h on the flat, tucked, no wind and allowed to speed up to that speed over about 20 seconds. Ontario loves putting stop signs everywhere instead of using yield signs or roundabouts, so I almost never get to accelerate to such a speed anyway.

You shoud be able to see at least 55-60 kph with a 1500 watt controller like the one mentioned above. At 1500 watts, it's pretty low amps so you should be able to stack a 24v battery with your current one and get away with it. I see nothing wrong with upgrading your bike to 72v with a low amp controller. That might get you into 55 kph. ( about 35 mph)

I ordered some of Doctorbass's torque arms so I am no longer afraid of adding in more torque to the bike, so a higher amp controller would be fine with me now What kind of 24v battery should I add? Can I mix a lipo battery in series with the lithium one I already have, or is that just a bad idea? I am still reading up all about lipo's and other battery options so for now I haven't made a decision on what to do in terms of batteries.

One last question. If I do get a top speed of around 55-60 km/h with the 1500W and 72V, what kind of range can I expect with how many ah? Say I were to add a 24V 10ah battery to my current system. What range could I expect? I figure that if I won't be going as fast as I wished, I might as well increase the range

Thanks so very very much guys for all of your help! This has been such a great learning experience for me and I'm glad there are so many helpful people on this forum

 

[dogman dan]

I would say I'm very happy with my 72v 20 amp lyens 9 fet controller. It wasn't real expensive, but comes with Lyens brain attached to it, so to speak. That can be priceless. Lyens really stands behind his stuff if you have problems. Often he can give you the right wire color codes, which can be real nice. Perhaps easily worth a few extra dollars compared to the cheapest possible competitor.

I run such a different motor on my 9fet 1500w controller that my range data is going to be pretty useless to you. That bike has a top speed of 25 mph so it's real efficient. But on similar motors and other 72v controllers I have seen about 50 wh per mile.

So 72v 10 ah will go at least 8- 10 miles at 35 mph. 15 k to 18k I'd guesstimate. Perhaps even slightly further with the 1500w controller. I was getting that range at slightly faster speeds with a 40 amp controller and 3000 w.

You can use 6s lipo to boost your current pack, then get more lipo later if you like it. Use diodes to prevent the bms getting damage on the lifepo4 pack. You will have to monitor the lipo seperately for low voltage.

 

[amberwolf]

It's an On Guard chain and the guy who sold it to me at the store (around $48 with tax) said you need a hydraulic cutter to get through it, so that's good enough for me

Or a battery-powered portable angle-grinder with metal cutoff disc. Probably take a few seconds more than a regular chain.

Also, sometimes I just need to take the busy road and the speed limit is 70 (60 now since it's under construction) and keeping up with the traffic would be a lot safer in my opinion as the drivers are very inattentive on this road.

That's probably true.

There are several roads here in the valley I do not take because I'd have to go at least 45MPH or more to not get flattened from behind by inattentive or impatient drivers. When I have alternate routes, I tend to avoid streets with 40MPH+ speed limits, but sometimes there simply is no other path.

Problem here is that the motor-assisted bike speed limit is 20MPH, and it's been enforced in some places...including a few where those roads go thru as the only alternative around or over a "mountain". I'd rather not have to deal with even a small chance of the "big three" tickets and fines, as that'd cost me at least an eighth of a year's pay that I can't afford.

But even when it's packed full of traffic, I can easily zip by in the far right lane since there is a lot of space between the curb and cars there

Enough space to completely clear their suddenly opening doors, without moving over at all (cuz you won't have time to react)? Cuz you never know when somebody just suddenly decides to open the door and let someone out when they're stuck in traffic, cuz they're just in too much of a hurry--and they never look first.

One last question. If I do get a top speed of around 55-60 km/h with the 1500W and 72V, what kind of range can I expect with how many ah? Say I were to add a 24V 10ah battery to my current system. What range could I expect?

That'll depend on how much power your bike uses up. I'd recommend using the simulator over at http://ebikes.ca/simulator to see what that might be, if you don't already have a wattmeter to test it (and then estimate upwards for faster speeds based on wind resistance/etc.).

 

[dogman dan]

Getting doored at 35 mph would be a thrill.

Don't mind me, after I got out of the hospital with $15,000 in charges,( insured thank god) I definetely became a real conservative street rider. For a few years I rode a 150cc scooter for the days I did want to get to work fast. On the way to turn it over to a buyer, I watched a stupid bitch sandwich a poor harley rider between her car and another at a stop light. Just reinforces my caution. Trusing any other driver, whether on your bike or driving a dump truck is for fools.

Personally, I'll take the back road at a speed I choose over jumping out into traffic and trusting those text reading sob's.

 

[mike662]

You can use 6s lipo to boost your current pack, then get more lipo later if you like it. Use diodes to prevent the bms getting damage on the lifepo4 pack. You will have to monitor the lipo seperately for low voltage.

The battery I currently have is Lithium ion. It doesn't say what the exact chemistry is, but I don't think it's lifepo4. Is it still ok to parallel the lipos with it? I think I will get 3 of these in parallel to create a 15ah pack. I'm still trying to figure out what charger to get and how to charge them. Lots of reading left to do. For now, my understanding is that it is best to disconnect the paralleled lipos and hook each one up individually to the charger along with the balance connectors. I would rather be able to plug one cable into the charger and charge all 3 batteries at once, but my understanding is that that is an advanced procedure. Also, how would I be able to monitor the lipos' voltage during a ride, seperately from the lion battery? Would I just connect the cycle analyst to the paralleled lipos?

I will also get a Lyen's controller, hopefully one that can take a higher voltage than what I plan to use for now so that when I do upgrade my voltage one day, I won't need to upgrade the controller.

Enough space to completely clear their suddenly opening doors, without moving over at all (cuz you won't have time to react)? Cuz you never know when somebody just suddenly decides to open the door and let someone out when they're stuck in traffic, cuz they're just in too much of a hurry--and they never look first.

I'll admit that I took the risk once by travelling in between two lanes as I had to hop 3 lanes to get to the left turn lane. The adrenaline made me take the risk but I don't plan on putting myself in such a position ever again as it's a stupid thing to do. As for travelling in the far right lane, I'd either go slower if I am within a car door's range, or if I want to go faster I will ride in the lanes that are blocked off by pylons due to construction. They're going to be blocked off for the next couple of years anyway so it's a pretty good spot to ride safely in without having to worry about cars.

 

[wesnewell]

Buy this controller and 24s lipo pack. Charge to 100V. hang on when you hit the throttle.

http://www.dhgate.com/72v-1500w-brushless-speed-controller-for/p-ff808081283845f5012848d41bf455fb.html

I like the thought of buying this controller as it is inexpensive, but can someone give me reasons as to why the Lyen might be a better investment?

Lyens controllers are well known. The Hua Tong controller is not. It was originally designed for a scooter and info on it here was basically nil until recently. Since I hooked mine up, it has become popular and several people are just now starting to find features on it that were common knowledge on Lyens controllers like regen braking, speed switches, etc. With this controller, you'll have to change connectors for the power and phase wires and add a connector and switch for cruise control if you want it. If you want some of the other features, you'll have to move some wires in the controller for the features you want. Luckily, there's plenty of wires that come out of the controller that you won't need, and you can use them. So, $33 for this one and some work, or ~$200 for Lyens 15 fet controller.

 

[mike662]

Buy this controller and 24s lipo pack. Charge to 100V. hang on when you hit the throttle.

http://www.dhgate.com/72v-1500w-brushless-speed-controller-for/p-ff808081283845f5012848d41bf455fb.html

I like the thought of buying this controller as it is inexpensive, but can someone give me reasons as to why the Lyen might be a better investment?

Lyens controllers are well known. The Hua Tong controller is not. It was originally designed for a scooter and info on it here was basically nil until recently. Since I hooked mine up, it has become popular and several people are just now starting to find features on it that were common knowledge on Lyens controllers like regen braking, speed switches, etc. With this controller, you'll have to change connectors for the power and phase wires and add a connector and switch for cruise control if you want it. If you want some of the other features, you'll have to move some wires in the controller for the features you want. Luckily, there's plenty of wires that come out of the controller that you won't need, and you can use them. So, $33 for this one and some work, or ~$200 for Lyens 15 fet controller.

This is actually very, very interesting. I do not need a whole bunch of features like regen or speed control. If anything, I'd like to be able to program the max current output of the controller. Could you please provide some links on the forum that talk about this controller? Is there a cycle analyst input on it (I am guessing not)? And you said hook up 100v to it. Is this controller capable to safely take 100v or is that near its max? For now I will probably do 72V but I'd like to keep the same controller in case I upgrade.

Just wondering about your bike. What kind of range do you get on it with your 5ah pack? Thanks for the help!

 

[mike662]

Scratch the request for links, I found them. Looks like I'm gonna get this controller, it's an awesome deal! Thanks so much for the link to that.

 

[dogman dan]

Looks like a good deal on a controller. What's the amps on it? 1500 watts would be a 20 amp. That would be about ideal for a commuter and 18s lipo.

Lots of info on the lipo noob links in the battery faq area. To run 18s you hook the batteries together in series. To charge all three at 6s, you disconnect and connect again using a paralell charging board. Not so complicated. Look at chargers that go at least 150 watts. The little 50 watt ones are too slow. Avoid the quad chargers too, those are designed for folks using smaller batteries than we do.

Monitor the lipo with one of the many low voltage warning devices or monitors in the HK catalog. Or you can use a CA to monitor the whole pack, but watchin at least at 6s level is more likely to stop you in time.

 

[wesnewell]

Looks like a good deal on a controller. What's the amps on it? 1500 watts would be a 20 amp. That would be about ideal for a commuter and 18s lipo.

Max amp output is 40+/-2. Not sure if the speed switches for it lowers that. I believe LVC is set at 62V, which would be about perfect for 18s lipo. I just hooked up a $3 dvm to my mine. I've run 18-24s without a problem.

 

[dogman dan]

Doncha just love the specs on stuff. 72v x 40 amp is 2880 watts. But they call it a 1500 watt controller.

The Lyens 9 fet 72v 20 amp controller I was talking about shows me 1500 watts on the CA in the real world. I would recomend that or a similar 20 amp controller. 3000 watts can melt your motor if you aren't carefull, I've proved that several times now to my self.

That is a pretty unbelievable low price for a decent 12 fet 40 amp controller.

 

[FMB42]

That controller in WN's link is interesting. I think a might consider using one for a "super cheap" 72V-ish build (i.e. GM DD, HK lipo, etc).

However, I don't think I'd need to be drawing 40 amps through it continuously tho. I figure 32-35mph would be plenty of speed for the type of riding I do (I would like a "lot" of torque tho).

Makes you wonder just how "cheap" you can go with a 1500 or so watt system...

 

[amberwolf]

Most likely it is only built for 1500W total dissipation--if you run it at the higher current *and* full voltage at the same time, it probably gets too hot too fast and dies, under sustained power usage.

 

[wesnewell]

It's rated for use on up to 1500W motors, but that could also mean rated for continuous use at 1500W. I know I've run it at 100V wot for a mile or so, and it didn't even get warm. Of course the motor won't draw full amperage under normal conditions for more than a few seconds. BTW, it's a 15 fet controller, not 12. Build quality is very good. A lot cleaner looking board than my infiinion EB215 board. Still don't know all the features it has yet, but we're getting there. Found regen, and speed control pads so far. There's lots of unused pads in it. I've got a spare one that I intend to experiment with in the near future and try and find out what some of the others are.

 

[dogman dan]

That's what I mean about doncha love the specs. This controller may well be able to do the full 3000w for some time, but meanwhile a guy with a battery just able to provide 1500 w before it dies a squealing death buys the controller thinking it's going to run at 1500 w. Then he hits the throttle and sucks 3000w from the poor ebay battery.

I dunno, just seems pretty wrong to call a 40 amp 72v controller 1500w.

 

[wesnewell]

There all rated like that afaik. My other controllers are rated at 500W and 800W, but they will both pull 30A at 48V.

 

[mike662]

So I've been doing a whole bunch of reading for the past week on lipos and still have a lot more reading to do, but I have a couple of questions.

These seem to be the best deal to get right now, but I think I'll wait to order once they have them in stock as I'm not in a rush to purchase yet: http://www.hobbyking.com/hobbyking/store/__15521__Turnigy_5000mAh_4S1P_14_8v_20C_hardcase_pack.html
Gonna get 10 of these 4S1P5Ah to run at 74V10Ah. Anyone have any experience on how quickly stock replenishes? And do us Canadians have to order from the China warehouse or is there a workaround to order from the USA warehouse?

As far as charging goes, I don't really need to charge too fast. What is a cheap charger that won't blow the packs up? It looks like the meanwell mod for bulk charging would be a good idea, no?

One last thing. I see that people parallel their balance connections. Doesn't this mean that the charger is no longer monitoring individual cells? Or will it charge one cell to the HVC and then if they are left in parallel they will just balance each other out?

That's all I can think of for now. If anyone can also recommend what is currently the cheapest device(s) to monitor LVC for each cell while riding, that'd be most appreciated I assume I'd need something to monitor every single cell during the ride, or would the pack voltage be good enough?

 

[Beavinator]

The only controller that I would ever consider using is a Lyen controller. They are the absolute best and for what you get they are very well priced! If you arent afraid to do a bit of work then I highly recommend the HS 3540 motors. In their stock form they are nothing special but if you add some cooling holes, larger phase wires and a temp probe you will have a bike that will easily take you to your desired speed and be very reliable. Disc brakes are an absolute must too. This is especially true for the HS motor because using regen is not recommended so the motor has some time to cool.

 

[wesnewell]

I'm sure Lyen's are very good. but I'd never buy one. Why? Because what you consider a good price, I consider an extravagant price. I consider anything over $50 for a 72V controller overpriced. I'll admit I've never seen one of his controllers, but build quality can't be better than the $33 72v controller I have now. The board is clean of jumper mods, and it even has a protective coating over the whole board protecting it from water shorts. It'll run 24s lipo without a problem, and it's cheap enough I could buy 5 or more for the price of one of Lyen's controllers. Well, that's my opinion since it seems everybody here has one.

 

[dogman dan]

I would not hold my breath waiting for HK to restock. Some items never do. Never order an out of stock item, it will hold up the whole order.

Idealy, buy batteries from the local warehouse, the shipping is often cheaper or even free. So the at your door price is not as high as it may seem.

Hmm, All controllers are underrated. Perhaps so. ALL the controllers I ever owned were rated by amps, not watts. All have poved to be pretty close to stated spec. The worst are the 20 amp controllers that actually put out 22. I'm not talking about some spike I see for a milisecond, but the power put out after the controller starts controlling.

I've been very happy with my Lyens products, because they come with Lyens customer support. Worth the $$ for me.