how do i make it go faster?

[boghopper]

Hi all, I'm new here and new to ebikes. I've been interested in the phenomenon for a while but they have always been out of my budget.

With the cost coming down and an increased desire to ride to work, I decided to go for it.

I restricted my budget to £250 and found an unbranded Chinese bike. It's obviously quite a low spec bike but its got an Ali frame, disc brakes and shimano gears.

Other than than I think it has a brushed 200w motor, 24v 12ah battery, pedelec sensor and throttle speed limited to 15mph.

It has a fairly decent controller with safety cut out on the brakes and under voltage protection.

As far as performance goes its ok. Bearing in mind I have nothing to compare it to other than my regular mountain bike I would say I am satisfied: I get to work in about the same amount of time but with about 50% of the effort. It is still going strong after the 12m journey and fully charges before I leave again.

But as you can guess, I would like a little more speed...

With peddling and throttle on the flat I cruise at about 17mph this gives me a journey time of about 45m. I would love to have top speed of 20-25mph giving me journey time of half an hour.

There is some resistance at top speed and I can't imagine I could pedal faster to achieve more speed. So I'm thinking:
A) derestrict some how
B) higher voltage
C) higher torque motor.

By the way, most of my journey is off road on flat terrain.

Any thoughts welcome!

Cheers
Dan

 

[Scottyf]

Depending on the hub drive you can overvolt to get to that 20mph figure. However it will cost you a new brushed controller and battery.

Really would need to know the motor and controller to really get a handle on it though. The logic is quite simple to get a push bike to go quicker in an ebike.

 

[morphix]

I find staying in top gear works best for me. I keep my chain on the largest chainset sprocket and I just move along all together quicker and easier under power.. I've heard flecc and others talk about fitting larger sprockets (i.e. 52T) to make it go faster. Then there's possibly increasing voltage to your motor, depending on your controller rating. Fitting better quality tyres and having a decent pump to get proper air pressure too can make a significant difference to performance.

 

[Deleted member 4366]

If you want it to go a lot faster, you could try throwing it off a cliff. Should get to about 120 mph.
Seriously though, probably the cheapest way to more speed is to get a Bafang BPM kit from BMSbattery. You get the motor in a wheel, controller, pedal sensor and other bits for less than £200 delivered. A suitable battery can be had for about £250 from them also, or you can get one from Ping - more expensive, but he has a good reputation.
Bafang BPM Rear Driving E-Bike Kit - BMSBATTERY
You could over-volt your present setup, but you'll probably need to change the controller and then you might get problems with your motor depending on which one you have. The BPM motor is very robust and it has real power. It should give you what you want, but will weigh about another 6 to 10 kg with the battery.

 

[banbury frank]

Hi

If you want to do 25 + MPH you need a good bike with Hydraulic disc brakes


Cost about £500 New

or look on Ebay type in bike then select distance nearest

Then you need a minimum 1,000 watt kit 48 volt lithium Battery

12 miles needs 12 AH to 15 AH battery one way

you then have a commuter bike to get you to work without breaking a sweat


If your budget is limited you can buy a 1,000 watt kit from BMS If you Email Annie

with your spec as above

Annie Lei <sales@ecitypower.com>

We sell kits and finished bike but mainly we sell service and support

BUT this costs

Above is the best unbiased information I have


Frank

 

[boghopper]

Hmmm do you think maybe 36v/48v is where its at right now?

Maybe the 24v systems delivering 200w are a little under powered. I seem to remember a human rider delivers about 250w so any less than that and you feel like you could do better on your own.

If my battery is made of separate cells maybe I could reconfigure it to a higher voltage?

I will take it apart and have a look. If that's no good then maybe a new battery is what I need. if my controller and motor aren't up to the higher voltage then maybe I will need to upgrade them too. It's a slippery (expensive) slope...

Good point morphix about the gearing, I could get a buy more thus way buy its more assistance I would prefer

Cheers
Dan

 

[banbury frank]

Hi boghopper

We have decided to make all our kits 48 volts so even a 10 AH battery is 520 watt hours

Also all our kits are restricted to 15MPH cough, cough , for on road use

we are in Banbury and open 7 days a week you are welcome to test ride one off our bikes fitted with a kit

Experience the XIPI grin

It is a no pressure sell we wont even ask for you tel number

WARNING

once you have ridden one off our bikes you will want one



This Is a open invitation to ALL

Frank

 

[stevebills]

Hmmm do you think maybe 36v/48v is where its at right now?

Maybe the 24v systems delivering 200w are a little under powered. I seem to remember a human rider delivers about 250w so any less than that and you feel like you could do better on your own.

If my battery is made of separate cells maybe I could reconfigure it to a higher voltage?

I will take it apart and have a look. If that's no good then maybe a new battery is what I need. if my controller and motor aren't up to the higher voltage then maybe I will need to upgrade them too. It's a slippery (expensive) slope...

Good point morphix about the gearing, I could get a buy more thus way buy its more assistance I would prefer

Cheers
Dan

Get a stealth bomber bike forget the rest they do 50 mph I am after one

 

[banbury frank]

Hi Steve

Thy do 50 Mph you have to get into training to catch one

Excuse my Humor


Frank

 

[NRG]

The average rider can output about 100w continous, a fit club rider could probably do 250w.

The 200/250w motor rating is just that a continous power rating, in reality the peak power achieved by the motor is far greater than this even with a 24v system.

You can get a bit more speed by increasing the voltage but you need to be aware that the controller will have a max rating so it should not be exceeded. Also, increasing speed increases aerodynamic drag and the power requirements for even a modest 5mph increase rise quickly so the faster you go means a more powerful controller is required and possibly a new battery to cope with the increased power draw and possibly a new motor to be able cope with the stress.

Legal issues aside ask yourself if you want a push bike with assistance or a moped with rider assistance....if the latter then get a moped it will work out cheaper in the long run.

 

[stevebills]

Hi Steve

Thy do 50 Mph you have to get into training to catch one

Excuse my Humor


Frank

I dont think you have seen me run just take a look below I can shift

YouTube - Man running faster than leopard

 

[Deleted member 4366]

I agree with NRG. As you go up to bigger and more powerful motors, you need bigger and heavier batteries. By the time you get to a bike that'll cruise at 20mph or more, you need bigger tyres and brakes as well and you've got something that looks like a moped and is totally illegal without licence and registration etc. If you have an accident, you'll be in really big trouble - possibly paying for the rest of your life - not worth it! It's easier and cheaper to buy a moped, which will be faster, more comfortable and have a better range.

 

[RoadieRoger]

Want to go faster ?

One of my machines is a Classic 1982 Suzuki CS 50 `Roadie` moped Scooter and to think I moan that it is limited to 30mph ! As suggested, if you want to go faster on your Commute get a Moped .

 

[Scottyf]

Hang about, his not asked to go moped speeds just a little more assistance / speed from the standard commute.

Getting a moped leaves you without freedom of a bike and we are not talknig about a super fast motorbike build.

About the question of a reconfiguring of cells. Theory - Yes you can do that at a limited amount amps. You'd get the higher voltage at the cost of current (Amps or range) thats before you start changing the BMS and the charger to suit the new config. No matter how the cells are arrange your total Wattage will always be the same.

Unfortuantly with your current setup as with all E-bikes you'd need to replace parts to get more out of the motor.
This would include at least a new Battery and controller to boot.

You may - depending on the quality of caps in the controller over volt the motor and controller effectivly by repalcing the battery to one with a higher voltage. You'd need to open the controller up to see what capacitors it has.
All starts to get a bit techy though and you could replace the caps if you handy with a soldering iron.

However its easier to replace the controller as a set.

 

[stevebills]

I agree he wants the freedom of a bike that uses the bike lane and best advice is use what you have for a year as it will give you more of a workout and you then might change your mind or upgrade to a bike with a 750 or a 1000 watt hub motor and they should give you about 21 mph unassited and cruise at 25 mph with peddling and it wont be cheap expect to pay over £700 for good a kit and a 48 volt lifepo4 battery

 

[Scottyf]

I believe police do not have time to really spend badgering cyclist.
They have more important things to do like think about there paycuts / Jobs - and bacon!

You'll never take me alive!

 

[stevebills]

All police should work for the minimum wage of £5.93 a hour a hour and see why people commit crime to live

 

[Mussels]

I believe police do not have time to really spend badgering cyclist.
They have more important things to do like think about there paycuts / Jobs - and bacon!

You'll never take me alive!

If you get stopped don't mention paycuts, that almost a guarantee to get your bike taken away for inspection.

As for the OP, his bike sounds very good for £250 and it's going to cost a lot more to get 25mph and cruising at that speed will get him noticed. I'd agree with the 50cc moped answer as being cheaper and easier overall.
If you want to stay electric there are plenty of cheap e-mopeds that will cruise at 20mph for that distance.

 

[Scottyf]

I pedal on the flat at around 20mph takes a bit more effort to get past that speed espcially if there is wind. Hardly think he would get noticed.

Don't get an E moped, you'll look like a tool.

 

[kitchenman]

By the way, most of my journey is off road on flat terrain.
Dan

I'm thinking of creating a new thread "route swapping" where members can try each others routes. My route is 15.2 miles, best time of 49.19 mins at an average speed of 18.7 mph - look out for it!