New 26" Ebike Conversion...

[jason72]

Hello guys once again!

A friend of mine trusted his bike to me so as to convert it to electric.
He wants it as a commuter for his job.
He lives in Athens [near me] and his job is located to Piraeus.
at least 20km distance just to go and another 20km to come back.
He will use the E75 national road [highway] so he wants a decent cruise speed at least 50km/h.
Here in Greece there is no restriction about ebike's speed so we wont have a problem.

I would like to propose me 3 different setups.
One cheap. One value for money. And one expensive.

Thank you for your time.

 

[dogman dan]

Might look into stock direct drive motors such as 9 continent 2807, Conhis, golden etc. Then run it on a 72v 20 amp controller.

You should have about 55 kph when fully charged, but not burn the motor up in 20k. More amps would risk a meltdown, and have even more speed.

I've been using the Lyens 9 fet 72v 20 amp controller. See Lyens in the for sale section.

A 72v 10 ah battery should be big enough, but he will have to charge when he gets there.

The motor and controller will be relatively cheap. The battery never is, and will cost a lot for all three variations. To carry only 10 ah, it will not be able to be a cheap 2c lifepo4.

The cheap option would be similar motors, but run on 48v 15 ah using pingbattery or some other 2c lifepo4. But you may only get about 40-45 kph out of that. So a 2806 winding would be faster. Also known to be a bit fast is the Mac speed version from emissions free.

 

[newb]

having lived in athens i know the roads and how the greeks drive so i'd suggest a geared motor for the extra torque. something like the bmc v2 spd (or mac equivalent) so they have the torque w/o having to up the amps to get the power to accelerate off the line and get out of the way yet have the spd of 50-60 kph at 48v. it wont be the cheapest way to go but its lighter, more efficient, freewheels and the extra torque will be appreciated in traffic and will tackle the hills in athens w/ greater ease.

 

[wesnewell]

1000W dd motor. 72V controller. 15-20ah of 18s lipo. About 60kph top speed.

 

[veloman]

1000W dd motor. 72V controller. 15-20ah of 18s lipo. About 60kph top speed.

I don't think building an ebike for a friend (evidence right there - he can't build it himself - doesn't have the knowledge or interest in anything more than turnkey) and using lipo is a good idea. Lipo is great for us hobbists, but normal people want to just plug and play, and have no worries of safety.

A123 lifepo4 from cellman with a mac geared motor is the way to go.

 

[dogman dan]

Likely the best compromise. 48v cellman battery and the speed version mac will get him about 50 kph. http://www.emissions-free.com/id47.html

Lipo's not for noobs.

 

[veloman]

48v on the high speed mac (6 turn) wants to go 65-68kph. Get the 8 turn if 48v.

 

[dnmun]

riding an ebike on a major roadway is a whole different dimension. why would he not choose a motor bike to maintain speed with traffic? there are several high speed commuters like GCinDC and DrBass but i don't see them on major roadways, maybe if it was all traffic jams like in moscow it would different. maybe.

 

[kmxtornado]

I'm no expert, but just wanted to suggest that if you're going to be responsible for building a bike for someone else, reliability should be your number one priority. He's relying on decisions you're making and you don't want him blaming you when @#$@#$ hits the fan.

 

[wesnewell]

Lipo's not for noobs.

Sure it is. It's just not for idiots. Handled properly, it's perfectly safe.

 

[john7700]

Lipo's not for noobs.

Sure it is. It's just not for idiots. Handled properly, it's perfectly safe.

Nitroglycerin, if handled properly, is perfectly safe. But I wouldn't put it in a starter chemistry set.

He has already mentioned that the guy doesn't feel safe even putting the kit together. I should think the owner should get to know bikes and how everything goes together before he tackles lipo safety.

 

[jason72]

i agree guys.
i rely on what dogman said. lipos are not for noobs like me and my friend.
i prefer the safe and reliable way.

so with lipos out only lifepo4 is in the game?
what about motor? which one? i saw different brands and types posted but i can only buy one.
as for the controller i think lyen will be glad to help me again.

thank you for your answers guys.

 

[MadRhino]

I'm no expert, but just wanted to suggest that if you're going to be responsible for building a bike for someone else, reliability should be your number one priority. He's relying on decisions you're making and you don't want him blaming you when @#$@#$ hits the fan.

If you build anything with performance for someone else, he will come back for any problem cause he didn't build his bike and doesn't know how to fix it. My motto is "don't give them fish, teach them fishing.".

Then, if you have to build for someone else, it has to be low performance, stock and legal. When he wants more power, show him how and let him do it by himself.

 

[dogman dan]

At least he doesn't have to deal with US liability law.

I didn't realize the fast wind mac on 48v was that fast! 40 mph no shit? not downhill 1/2% or tailwinded? No pedaling? 14s lipo or less?
I thought it was more like 50kph on a more typical "48v" of about 54v actual.