A new kit, what would you recommend?

[eriwen]

Hi!
I just decided to build an electric bike out of my mountainbike. So I have a few (a lot) of questions to ask you all.
First I am going to state my values:

1. I am going to use it for commuting to work 6 miles every day (so 12 in total).
2. It is going to be used on trails in the woods and some other types of offroad. (for fun)
3. This is the bike that I own and it has got 27 gears (9 disks in the back stack). With hydraulic disk brakes. http://www.merida.se/arkiv.aspx?menuid=99&prodid=12916
4. I do not wish to charge it when on the move, and would like to also use it as a bike quite often. So as little resistance as possible is appreciated. But if there are any advantages with a “Direct” motor, it is welcome.
5. I would prefer it to be a rear wheel hub motor. (quite hidden and no chain involved).
6. I would prefer a “bottle” battery that’s mountable in the water bottle mount (just for the estetics). I hear people talking about Samsung cells, but anything is welcome.
7. It would be awesome if it was in some degree watertight. But could also make it watertight myself. Because i may use it in the fall (rain and snow up here in Sweden).
8. My price range is about 4-500 usd but any recommendation is welcome!
9. I would like some pretty good “go” in it so a 1000w 48v motor, is it too much, too little or perfect? Speeds around 25-31 mph are preferred.

Now, it’s a jungle out there of stuff.
Which “kit” would you recommend, where can I get it? Which kit are you using and are happy with?

Really happy for answers!

Sorry for my English, I don’t use that often.

 

[motomech]

Hi!
I just decided to build an electric bike out of my mountainbike. So I have a few (a lot) of questions to ask you all.
First I am going to state my values:

1. I am going to use it for commuting to work 6 miles every day (so 12 in total).
2. It is going to be used on trails in the woods and some other types of offroad. (for fun)
3. This is the bike that I own and it has got 27 gears (9 disks in the back stack). With hydraulic disk brakes. http://www.merida.se/arkiv.aspx?menuid=99&prodid=12916
4. I do not wish to charge it when on the move, and would like to also use it as a bike quite often. So as little resistance as possible is appreciated. But if there are any advantages with a “Direct” motor, it is welcome.
5. I would prefer it to be a rear wheel hub motor. (quite hidden and no chain involved).
6. I would prefer a “bottle” battery that’s mountable in the water bottle mount (just for the estetics). I hear people talking about Samsung cells, but anything is welcome.
7. It would be awesome if it was in some degree watertight. But could also make it watertight myself. Because i may use it in the fall (rain and snow up here in Sweden).
8. My price range is about 4-500 usd but any recommendation is welcome!
9. I would like some pretty good “go” in it so a 1000w 48v motor, is it too much, too little or perfect? Speeds around 25-31 mph are preferred.

Now, it’s a jungle out there of stuff.
Which “kit” would you recommend, where can I get it? Which kit are you using and are happy with?

Really happy for answers!

Sorry for my English, I don’t use that often.

My price range is about 4-500 usd but any recommendation is welcome!

It all starts with money, so we will start there.
You can build a 30 Kph road bike with a mini-motor for this amount. But no trail bike capabilities to speak of.
If you were to add, perhaps, $300USD, you can build a light duty trail bike by using the following products.
You need to use a geared motor for less weight(some will debate this)and better responsiveness @ lower Volts.
To retain your bikes gearing system, the recommended motor is the Bafang CST;
https://bmsbattery.com/ebike-kit/492-bafang-36v500w-cst-rear-driving-hub-motor-ebike-kit.html
Order the motor alone to save on shipping and build a wider/stronger wheel ASM using a Alex DM24 rim and custom 13/14 ga. spokes. This will allow a 2.5 inch off road tire to be mounted.
You will need at least a 25 Amp controller and that means at least a 25 A max discharge rate battery, so "bottle style" batteries are out.
Your commute does not need much battery, but hills(off road) eat up the battery's capacity very fast. But a larger battery add weight. I would recommend a 36V Li-ion w/ at least 25 A max. dis-charge "shrink wrap" style from this group;
https://bmsbattery.com/70-36v-li-ion
Your challange will be to mount it in the open triangle of your bike;
http://endless-sphere.com/forums/viewtopic.php?f=3&t=12847
From BMS Battery, you will also need a spoke wrench and a throttle. Plus from other vendors, a number of other things that will add to the cost.
When this done, you will have a light duty Etrail bike. No jumping or climbing over rocks and logs and no very steep hills. It will not equal a trail motorcycle, if you want that, expect to spend 2 or 3 times your budget.

 

[wesnewell]

http://endless-sphere.com/forums/viewtopic.php?f=3&t=66302
Just edit original post.

 

[dogman dan]

You mentioned one thing that stuck out to me. You want to use the bike as a normal bike at times. One thing I often say, "don't ruin your favorite bike with a motor". Since your bike sounds like a pretty nice one, you might want to leave it alone. Get something a bit cheaper, used most likely, but still an OK bike. Put the motor on that bike. Look for one with 7 rear gears.

Otherwise, the above advice is perfect. More money, especially if you want higher speeds and power. The money will be spent on larger batteries than the bottle type ones.

 

[TheBeastie]

Yeah its a nice bike, I am just thinking in terms of keeping as many original components as possible.
a Bafang CST will allow you to keep your cassette but its not a cheap motor so it ruins your $500 budget which I think is unrealistic for a nice bike.
As for keeping your hydraulic brakes as is I recommend a magnetic movement sensor discussed here. http://endless-sphere.com/forums/viewtopic.php?f=3&t=69159#p1044105

As for a complete kit I don't recommend a china built wheel (unless its from em3ev.com) because they don't even attempt true or dish them)
I have now a self built Bafang CST with its original cassette and original gear like the hydraulic brakes and its great but took a fair bit of effort.
As far as I know hub motors are easier to swap out then mid-drives, if u want to go back to normal.

Edit, whoop my 1000th post!

 

[eriwen]

A big thanks for all of your reply's! Helps alot.

After reading through all the replies, i am considering leaving the linked bike and going for an older one with a 7 disc casette in the rear. It looks exactly the same but is a 2008 model of almost the same bike. It has no disc brakes.

One thing that might make me keep the original linked Merida is if i could change the back cassette to a 7 disc one...
- is it possible without changing anything else exept mabye the calibration?
- If i add a new 7disc cassette it will be compatible with most kits?
One other reason to keep the "nice" bike is that it is more sturdy for higher speeds.

So: Do you recommend disc or "v-brakes" for the given kind of speeds? And if i was to buy a new cassete - is there any kit that could match it all (given values with added battery capacity)

Momotech: yes, 300USD extra is possible if needed. I have a little bit limited recources when it comes to workshops for assembling a rim, but if it gives the best result, it's a must do. Is it hard to get the rim "straight" (no wobbling)? Which capacity on the battery would you recommend? (for say..31 miles of riding). And if i changed my bike to an older version of my Merida, that has 7 gear cassete, is there any kit that you could see as suitable? (sorry for changing bike)

Wesnewell: i will!

dogman dan: yeah, the thought has trough my mind. I Have an old MTB also, mabye that's a better bike to start out with. And it has a 7 gear casette.. It may also reduce the risk of "theft".
Do you have a complete kit to recommend or do you vote for the Bafang CST selfbuild? I would prefer a kit :/. Higher speeds and power would be awsome! And thanks for the recommendation what to look for, it helps alot!



TheBeastie: With a possible change of bike, what would you recommend?
Yeah, thats also why i want to go with the rear motor, to be able to change it back if i feel to lazy . So em3v.com has acceptable quality/kits? Congrats to the 1 000th post !

would one of theese work?
http://em3ev.com/store/index.php?route=product/product&path=45&product_id=186
Mabye i do not need 1000w to get good torque/speed? as many other things the watts may not tell the whole truth.. and it says that the kit could deliver 50 km/h or 30Mph.

This one has no need for control-unit, as it is built in?
https://bmsbattery.com/ebike-kit/429-magicpie3-sine-wave-rear-driving-ebike-hub-motor-ebike-kit.html#/wheelrim-26_1_5_1_95

https://bmsbattery.com/ebike-kit/529-q11-48v1kw-rear-driving-e-bike-conversion-kit-ebike-kit.html

Last question: do i need a freewheel? And which battery would fit one of these?

Also a big thanks for the links, it really helps to get a visual representation and "where to buy". I really appriciate your answers and recommendations.
P.s sorry for a late answer and wall of text, it's the time deelay.

 

[fellow]

If you want to pedal it, Q100H is perfect for the job when filled with ATF oil. Click on my triebfluegel signature for for info about the parts needed. That motor however can't defy the laws of physics, and will do no burnouts. At 48V, it is good for 32 km/h. This motor is 2,2kg. At 75.6V and 1kW it will do 40km/h-50km/h predicted, but chances are it will burn out. Clutch is its weakest point.

Next on are Q128H at 48V-60V (3kg), Mac 10t at 48V (4.3kg) or Mac 12T at 72V (4.3kg). Those motors are good for about 40km/h to 50 km/h, and are a good choice when target power is more than 1kW.

Where to buy things?
48V controller (even called S06S, matches Q100H motor): http://www.aliexpress.com/item/Electric-Bike-Brush-less-Controller-750W-48V-Max-Current-14A/1749808028.html
Q100H motor (choose the 36V, 201rpm) and 7 speed freewheel: http://www.bmsbattery.com
Mac motor and controller: http://em3ev.com
Rims, 26" 25c wide: http://26bikes.com/shop/parts/rims-and-rim-tapes/dirt-street/prod/ex-dh26
48V charger http://www.aliexpress.com/item/100-240VAC-48V-54-6V-DC-2-0A-Lithium-LiPo-Battery-Charger-E-Bike-charger-suitable/1043911845.html
Panasonic NCR18650PF cells (tab version prefered) https://www.akkuteile.de/lithium-ionen-akkus/18650/ or http://eu.nkon.nl/rechargeable/18650-size.html

 

[wesnewell]

Whatever country you're in, It's much cheaper buying from a volume seller within your own country than paying for shipping from China. 48V 1000W kits usually provide the best bang for the buck. For a battery, I won't use anything but rc lipo. It has plenty of power in a smaller and lighter package than most other chemistries. You just have to build your own pack and provide a charging method. For your commute, a 10ah 12s pack would be plenty at a cost of $150 to $200 with ~$100 more for a charger and/or bms. I could put a 10ah 12s pack together in under 5 minutes.
http://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=48v+1000w+rear&LH_PrefLoc=1&rt=nc&LH_FS=1

 

[motomech]

A big thanks for all of your reply's! Helps alot.

After reading through all the replies, i am considering leaving the linked bike and going for an older one with a 7 disc casette in the rear. It looks exactly the same but is a 2008 model of almost the same bike. It has no disc brakes.

One thing that might make me keep the original linked Merida is if i could change the back cassette to a 7 disc one...
- is it possible without changing anything else exept mabye the calibration?
- If i add a new 7disc cassette it will be compatible with most kits?
One other reason to keep the "nice" bike is that it is more sturdy for higher speeds.

So: Do you recommend disc or "v-brakes" for the given kind of speeds? And if i was to buy a new cassete - is there any kit that could match it all (given values with added battery capacity)

Momotech: yes, 300USD extra is possible if needed. I have a little bit limited recources when it comes to workshops for assembling a rim, but if it gives the best result, it's a must do. Is it hard to get the rim "straight" (no wobbling)? Which capacity on the battery would you recommend? (for say..31 miles of riding). And if i changed my bike to an older version of my Merida, that has 7 gear cassete, is there any kit that you could see as suitable? (sorry for changing bike)

Wesnewell: i will!

dogman dan: yeah, the thought has trough my mind. I Have an old MTB also, mabye that's a better bike to start out with. And it has a 7 gear casette.. It may also reduce the risk of "theft".
Do you have a complete kit to recommend or do you vote for the Bafang CST selfbuild? I would prefer a kit :/. Higher speeds and power would be awsome! And thanks for the recommendation what to look for, it helps alot!



TheBeastie: With a possible change of bike, what would you recommend?
Yeah, thats also why i want to go with the rear motor, to be able to change it back if i feel to lazy . So em3v.com has acceptable quality/kits? Congrats to the 1 000th post !

would one of theese work?
http://em3ev.com/store/index.php?route=product/product&path=45&product_id=186
Mabye i do not need 1000w to get good torque/speed? as many other things the watts may not tell the whole truth.. and it says that the kit could deliver 50 km/h or 30Mph.

This one has no need for control-unit, as it is built in?
https://bmsbattery.com/ebike-kit/429-magicpie3-sine-wave-rear-driving-ebike-hub-motor-ebike-kit.html#/wheelrim-26_1_5_1_95

https://bmsbattery.com/ebike-kit/529-q11-48v1kw-rear-driving-e-bike-conversion-kit-ebike-kit.html

Last question: do i need a freewheel? And which battery would fit one of these?

Also a big thanks for the links, it really helps to get a visual representation and "where to buy". I really appriciate your answers and recommendations.
P.s sorry for a late answer and wall of text, it's the time deelay.

You are starting to over-think this thing and you are starting to roam all over the place.
We have gone from a budget of $500 to an EM3ev kit of $1500 shipped, to a giant Magic Pie that is not for the trails.
What do you want to do with an Ebike? And how fast to you want to go?
You need to focus your goals.