Newbie needs help with this sytem stats

[electricbandit]

Hello I am currently new to ebikes but have tried o figure it out on my own for the most part but know i need help.

I am currently looking at this set up from sickbikeparts because i was going to get a cyclone kit but the shipping is twice what th kit costs.
http://www.sickbikeparts.com/catalog/product_info.php?cPath=26&products_id=170&osCsid=rocuhb0eaioskfopavg0nmuch2

and i was going to run 2 24volt 18ah batterys in series to extend my range from sick bike parts
http://www.sickbikeparts.com/catalog/product_info.php?products_id=172&osCsid=rocuhb0eaioskfopavg0nmuch2


what i need help determining is range and top speed i dont think im doing the math right. the bike weighs 42 pounds has a 3 speed internel hub with 26 inch wheels

i have been calculating range as 24v x 40ah = 960wh then 960 divided by 650watts(motor ouput) 1.47 x 32kms(the fastest i legally can travel but will try faster on trails) which if i did it right theoretically gives me a range of 47 miles?

i am also thinking of upgrading to a 36 volt controller to increase speed but how do i increase amps?

 

[docnjoj]

If you now have a 24 volt battery you will need to increase it to 36 volts to get the increase in speed. Also your 47 miles is a bit overstated due to efficiency losses due to wind resistance, friction, hills etc. Your motor at times will draw more than 650 watts, even at 24 volts. The 36 volts will be a bit more efficient unless you use the additional 12 volts to increase speed. The 36 volt controller might have a low voltage cutoff that will not accept 24 volts without a 36 volt battery. The parallel 24 volts will give extended range over a single 24 volt battery, but probably not double due to the above mentioned efficiency losses. I hope this helps a bit.
otherDoc

 

[electricbandit]

Also your 47 miles is a bit overstated due to efficiency losses due to wind resistance, friction, hills etc. Your motor at times will draw more than 650 watts, even at 24 volts

ya i kinda figured it might be i was kinda trying to replicate how companys do thier math realistically i thing 30miles is more realistic?

 

[wesnewell]

Please go to the User Control Panel, select Profile, and then enter your city, state/province, and country into the Location field (country minimum). This will help people help you. Example: Wylie, TX, USA. Without knowing what country you are in it's hard to make any recommendations. Thank you.

 

[dogman dan]

1 ah per mile with 36v batteries is a good rule of thumb for 20-25 mph. This rule has a lot of fudge factor in it, for leaving some extra capacity.

This rule is for lithium, so half that for lead. Call it 1.3 ah per mile for 24v, and your range will be about 7 miles. 9 ah usable / 1.3 ah This can be doubled by going slow, say about 15 mph, but 15 miles is going to be about your absolute max you should go. It will be possible to get more, but it will damage the battery to discharge it deep.

The point? Get lithium. Then you will have about 20-30 miles of range from 20 ah of it. Bottom line is, you will use 20-30 wh per mile regardless of the kind of motor or battery.

 

[electricbandit]

1 ah per mile with 36v batteries is a good rule of thumb for 20-25 mph. This rule has a lot of fudge factor in it, for leaving some extra capacity.

This rule is for lithium, so half that for lead. Call it 1.3 ah per mile for 24v, and your range will be about 7 miles. 9 ah usable / 1.3 ah This can be doubled by going slow, say about 15 mph, but 15 miles is going to be about your absolute max you should go. It will be possible to get more, but it will damage the battery to discharge it deep.

The point? Get lithium. Then you will have about 20-30 miles of range from 20 ah of it. Bottom line is, you will use 20-30 wh per mile regardless of the kind of motor or battery.

The batteries from sick bikes is lifepo4 and i wanna run them parellell

 

[electricbandit]

Please go to the User Control Panel, select Profile, and then enter your city, state/province, and country into the Location field (country minimum). This will help people help you. Example: Wylie, TX, USA. Without knowing what country you are in it's hard to make any recommendations. Thank you.

I checked says everything already

 

[wesnewell]

Try changing it to this: Victoria, BC, Canada. Assuming you're in that Victoria. Or just Canada.

 

[dogman dan]

Pardon me for assuming 24v 18 ah was lead. It's an odd size for lithium, so I assumed lead.

Oughta get 15-25 miles then, depending on the speed.

 

[electricbandit]

Try changing it to this: Victoria, BC, Canada. Assuming you're in that Victoria. Or just Canada.

Ya i am theres only one victoria british columbia lol :wink:

 

[electricbandit]

Pardon me for assuming 24v 18 ah was lead. It's an odd size for lithium, so I assumed lead.

Oughta get 15-25 miles then, depending on the speed.

You are Pardoned Sir. Ya its a good small size to. The measurements ar 13x5x5 and What do you think i could get for milage with 2 of them in parralel