How to make my bike go faster?

[cwah]

Hello there,

Some of you have already seen my bike:

Specs:
24kg
36 km/h (22mph) max speed
28 km (18 miles) max distance
250W Conhismotor with 36V10A Li(NiCoMn)O2 battery

I'm quite happy with the speed but I'd like to have little more (as always lol). I'd like to have a better acceleration and reach 45-50km/h (30mph). And I was wondering if there is any safe way to do that?

Could I buy some Lipo and combine that with my actual 36V10A Li(NiCoMn)O2 battery? I'd like to have all batteries in my backpack.

 

[Drunkskunk]

48V would make it go faster, but I would give that little motor 50%/50% of living or melting to a puddle at that power level.

I'd only take that risk if you can afford a new motor.

 

[AussieJester]

Volts for speed, more amps for better acceleration is the way she works, as mentioned above though, both come with consequences :wink:

KiM

 

[mike662]

Looks like you're starting the same quest I started about 1.5 months ago. Take a look in this thread I started back then, it is pretty much the same questions you have except your motor is smaller. http://endless-sphere.com/forums/viewtopic.php?f=3&t=31367

 

[cwah]

hmm... it seems that I won't be able to go faster if I want to keep my motor alive?

 

[d8veh]

The easiest and cheapest way to get a bit more power is to solder the shunt in the controller. It would be best if you had an ammeter or wattmeter on your bike first so that you can see the difference. You're probably getting about 15 amps max at the moment, and you can take it up to about 20 amps without doing too much harm. This mod will give a useful gain in acceleration, climbing ability and average speed. The mod is not reversible, but if you go too far and want to go back, you can get a replacement controller for about £15.
To do the mod, you can search this forum or the UK Pedelecs forum for "soldered shunt" and you should find instructions.
Basically, you remove the controller, unscrew the end-plates, unscrew the three heatsink screws in the side and slide out the circuit board. The shunt looks like a bit of coat-hanger wire. You cover the surface of it with solder - about 1/3 of it's length will probably be about right. Be careful that big blobs of solder don't work their way through the circuit board onto the other side. If you can't notice much difference in the power, solder half-way along the shunt. It doesn't matter which end you work from. If you're lucky, most controllers have the shunt positioned behind one of the end-plates, so you don't have to remove the circuit board.
Don't over-do the soldering. Don't be greedy: You don't want to go past 20 amps else the controller will get too hot and the increased torque can damage the gears in the motor. I reckon about 1/3 should be enough.

 

[theRealFury]

Yea sadly it looks like if you want to join the 30MPH club then you need a new motor I’m afraid. It takes me about 800-1000watts of power to cruise at 30mph and considerably more than that to accelerate up to 30mph and I just don’t think your motor can handle that. It may take it for a short while, but in the end you will shred the gears inside.

Unfortunately I did the same thing as you early on in my Ebiking addiction... I bought a small 250w geared hub in the hope it would answer all my prayers.... sadly it lasted 6 months and I outgrew it lol. Happens to us all I’m afraid

 

[Thud]

Pedal like Lance Armstrong...then add steroids, anphetimines & EPO untill you hit your desired speed.

Or just add batteries (voltage) & amperage through controller mods untill you get your speed....either way will cost money & sorten the life of some components. (yours or the bikes )







money = speed, how fast you wanna go? oh I almost forgot...speed kills.

 

[dogman dan]

Put 72v controller on that thing and it will go fast. The question is, for how long? Enough over wattage and the extra watts simply make heat, which fries the motor. I wouldn't take that thing over 800w. 36v-20 amps.

What you have there, my freind, is a small wattage kit designed perfect to do what it does. Provide and assist while you pedal.

To hot rod it is like hot rodding a 1200cc ford pinto. It can be done, but it's stupid. Start with a ford mustang, and the basic equipment can handle a bit more.

The "standard" recipe for fast is this. Direct drive motor, 72v 40 amp controller, and batteries able to put out about 60 amps continous. So A123's, headways, or hobby lipo. Usually about $1500 cost or more.

You were all concerned about stealth last week, but believe me, 30 mph or faster without pedaling is not stealthy at all. But the standard 48v 20 amp controller direct drive motor kit , at 25-30 mph while still pedaling for show can be stealthy enough. 25 mph just pedaling is done all the time by fit cyclists so you don't stick out so much as when doing 35 mph not pedaling.

 

[cwah]

oohhh nooo that's terrible. I'm going to contact the seller to see what we can do. But I suppose we can't do anything...

And by the way, I'll always peddle so I should be stealthy. I remember during the cyclism championship, cyclists can reach easily 28mph (45km/h). So if I peddle at the same time, I should be more than stealthy!!

I'll try to see for the shunt. Look for the search in the forum. But I feel that I'll have to purchase a new bike and a new kit...

 

[dogman dan]

Yup, continuing to pedal is one of the keys to stealth. But once you get real speed, nothing helps. 35 mph and up, you need really gigantic gears to keep pedaling for one, and you just stick out like crazy going that fast too.

But you can get a typical dd motor kit, and usually they will cruise at 27 mph or thereabouts when run on 48v batteries. Then if you get strong enough batteries, you can run high amperage controllers that give you great take off from the line. Which again tends to trun a head or two it it's that fast.

Welcome to the ebike progression, we start out with 15-20 mph and love it. But right away we see how nice more would be. 8)

Every ebike is some kind of compromise, efficient but slow, climbs hills well but slow, fast but climbs less well, etc. My current favorite bike is slowish, at 25 mph max, but climbs a wall. Takes off the line nice, and if you pull hard, can wheelie. It's a good combination of compromises, that does more that some other bikes. A complicated battery is the downside.

http://endless-sphere.com/forums/viewtopic.php?f=4&t=27364

 

[amberwolf]

Welcome to the ebike progression, we start out with 15-20 mph and love it. But right away we see how nice more would be. 8)

Especially after you get it on a race track without any traffic in your way.