Mountain Bike Reviews Forum banner

1 - 20 of 43 Posts

·
Registered
Joined
·
4,179 Posts
Discussion Starter · #1 ·
I'm curious if they make an E-bike motor/ battery product that can be added (and removed as needed) to a standard MTB?

Thanks.
 

·
Registered
Joined
·
4,179 Posts
Discussion Starter · #4 ·
Do you mean removed *quickly*? There are tons of add-on motor kits out there, but most of them require at least 30 minutes and significant tools to install/remove.

-Walt
Well, anything that could be removed in an hour and didn't require permanent modifications to my bike would be acceptable.

Thx

Sent from my SM-G892A using Tapatalk
 

·
Registered
Joined
·
4,179 Posts
Discussion Starter · #6 ·
Thanks. Sounds like an integrated solution is the only thing that is feasible at this time.
Take care.

Sent from my SM-G892A using Tapatalk
 

·
Registered
Joined
·
65 Posts
Here ya go... :)

I regularly remove it in under 5 minutes with a hex key and a screwdriver. Three screws and a hose clamp for the motor and mount. Pull three electrical connections and un-velcro the battery bag. I leave the chain ring and throttle.

Cost me $400. Adds 5 1/2 Lb total. Up to 450 watts. It really gives a nice assist up Northern California hills, and is imperceptible on the downhills.

https://endless-sphere.com/forums/viewtopic.php?f=28&t=96769

ebike6.jpg

Of course it is DIY... :eek:
All parts are off the shelf except the motor bracket. Does require wiring (soldering). In 10 years, if anything fails, all parts are generic. (I'm curious to see what happens in 10 years when a Levo PCB frys...)
 

·
Registered
Joined
·
254 Posts
LIFT-MTB or a similar simple MY1018 motor with custom mounting bracket that removes in minutes. 👍
 

·
XC iconoclast
Joined
·
2,005 Posts
Here ya go... :)

I regularly remove it in under 5 minutes with a hex key and a screwdriver. Three screws and a hose clamp for the motor and mount. Pull three electrical connections and un-velcro the battery bag. I leave the chain ring and throttle.

Cost me $400. Adds 5 1/2 Lb total. Up to 450 watts. It really gives a nice assist up Northern California hills, and is imperceptible on the downhills.

https://endless-sphere.com/forums/viewtopic.php?f=28&t=96769

View attachment 1247936

Of course it is DIY... :eek:
All parts are off the shelf except the motor bracket. Does require wiring (soldering). In 10 years, if anything fails, all parts are generic. (I'm curious to see what happens in 10 years when a Levo PCB frys...)


This is exactly (well almost exactly) what I was wishing for too.

Turnigy D2836/8 1100KV Brushless Outrunner Motor $15.02, up to 336W

Turnigy Plush 30amp Speed Controller $14.18

Vktech Gold-plated Bullet Connector (3.5 mm 40pcs) $8.99

What battery? Does it have to be 12V to fall within the 7.4 - 14.85 V motor volt range? Or can it be compatible with a more normal Li+ 24V 250W battery?

You think an LBS that works on e-bikes would even attempt to do this for someone? I guess I can get my stepson to do it for a few $$, he has a soldering kit and builds his own computers so this shouldn't be hard for him.
 

·
Registered
Joined
·
65 Posts
This is exactly (well almost exactly) what I was wishing for too.

Turnigy D2836/8 1100KV Brushless Outrunner Motor $15.02, up to 336W

Turnigy Plush 30amp Speed Controller $14.18

Vktech Gold-plated Bullet Connector (3.5 mm 40pcs) $8.99

What battery? Does it have to be 12V to fall within the 7.4 - 14.85 V motor volt range? Or can it be compatible with a more normal Li+ 24V 250W battery?

You think an LBS that works on e-bikes would even attempt to do this for someone? I guess I can get my stepson to do it for a few $$, he has a soldering kit and builds his own computers so this shouldn't be hard for him.
The bike works very well! If you are seriously interested in building something like this, then I would suggest that you skim the build thread on Endless Sphere, and ask questions there. It would also be worthwhile to follow the recipe (there are Very Good Reasons!) and Make No Substitutions on critical (most) components. That way you get to take advantage of some actual engineering and development. At least read the Bill of Materials post on page 4.

I'm sure your stepson could solder everything together and set up the speed controller. He would need a cheap heavy soldering iron to do the power connections. The motor mount would be the tricky part, as all bikes are different. I could post up some drawings over on ES, and i'm sure you could find a small machine shop that could finesse the details and attach the motor to your bike.

If you have the ability to replace a chain, replace front chain rings, and tune a derailleur, you could do the rest. Otherwise, an E-Bike shop might come in handy.

Just FYI - The motor you selected will spin the PEDALS at 500 RPM, but with no power at all...
 

·
XC iconoclast
Joined
·
2,005 Posts
The bike works very well! If you are seriously interested in building something like this, then I would suggest that you skim the build thread on Endless Sphere, and ask questions there. It would also be worthwhile to follow the recipe (there are Very Good Reasons!) and Make No Substitutions on critical (most) components. That way you get to take advantage of some actual engineering and development. At least read the Bill of Materials post on page 4.

I'm sure your stepson could solder everything together and set up the speed controller. He would need a cheap heavy soldering iron to do the power connections. The motor mount would be the tricky part, as all bikes are different. I could post up some drawings over on ES, and i'm sure you could find a small machine shop that could finesse the details and attach the motor to your bike.

If you have the ability to replace a chain, replace front chain rings, and tune a derailleur, you could do the rest. Otherwise, an E-Bike shop might come in handy.

Just FYI - The motor you selected will spin the PEDALS at 500 RPM, but with no power at all...

Yeah I realized I looked at the wrong motor soon after.

FZ, you should try to patent something like this, it has way more potential than you even realize. If you or someone else can get it to the point where the chain / motor / battery can be removed within 1-2 minutes, it would be a great alternative to a mid-drive because you remove those three components and you have a perfectly normal bike that just has a large chainring on the other side. And then riders, instead of having to shuttle with two trucks, can simply ride back up faster after they are done with a long downhill session. They ride down without the components and then slap them on at the bottom. These would sell like hotcakes because they are light, cheap, and easy to take off and put in a pack.


What I'd personally like to do (and even sell on Amazon, etc.) if I had more mechanical skills:

1. Chain guard on large chainring
2. Remote wireless throttle or push button on/off for watts, no wires from the handlebar, only from/to the battery
3. Chain that's easy to remove, with a user-friendly missing link that you push in and quickly break & put in pack
4. Cassette-based 0.5 lb LiPo battery, plugged in securely to some type of housing attached to one of the tubes. I'm calculating about 2.5 miles worth of battery uphill at 250W, is that in the ballpark? The kit could come with maybe 5-6 of these batteries that you simply plug in to the housing (kind of like printer ink) and then connect the battery wire to the motor in seconds
5. Kit bag with all components, extra batteries, motor, chain, any screwdrivers, etc. for attaching at the bottom of the mountain


If someone could make a kit like that for around $250 that weighed under 10 lbs with the extra batteries...
 

·
Registered
Joined
·
65 Posts
Some criticisms if this:

  • an unprotected and unmanaged LiPo pack lacking required protective structure, yet being evangelized to the naive, terrible, unsafe
  • less than 100 Wh, grossly inadequate for many riders, easy to be light weight when there's no battery
  • lack of PAS, along with advocacy for removing the throttle in favor of an on/off button! is that a joke?
  • no means of locating the chain in the proper plane, along with use of a chain not designed to tolerate it
  • no chain tensioner
  • lack of freewheel meaning the motor creates drag while pedaling, mitigated by how small and ineffectual the motor is
  • 9T cog wears like cheese, as evidenced in the ES thread already
Seriously, no one in their right mind should be interested in this; perfect for ES, not a good topic for MTBR. An abomination, and I'd advise that any posting that advocates unprotected LiPo on an e-bike is out of bounds. Bikes, not bombs.

Please allow me to rebut -

"an unprotected and unmanaged LiPo pack lacking required protective structure, yet being evangelized to the naive, terrible, unsafe"
1. I did not evangelize anything to do with batteries. Batteries were just not something I covered in the ES build thread. I believe I only mentioned what battery I was using in passing...
2. Your X-ray vision is faulty. I do have the pack armored. It's in the pouch. Again, not what the build thread was about.
3. The bike has three independent battery protection systems.
4. I agree. DON'T BE UNSAFE WITH BATTERIES!!! Or anything else which contains energy - Gas Cans, Air Compressors, Garage Door Springs, Moving Cars, etc.

"less than 100 Wh, grossly inadequate for many riders, easy to be light weight when there's no battery"
1. I like a minimalist assist system. I get my exercise while avoiding overstressing my knee. My standard ride is 10 miles, 1000 feet climbing and about 1 hr 15 minutes, 3x per week. I take my non-Ebike about 1/3 of the time, when my knee is feeling good, and my ride times are similar.
2. Wow, you make me feel like Superman! Not bad for an overweight 60 year old with a messed up knee.
3. Here's a snip from a ride I reported last year:
Went for an exploration ride Friday with a couple of friends. I had the only E-Bike . Lots of long steep (22%) loose gravel grades. 11 miles, 1700 feet of climbing. I cleared all the grades (barely), the really strong rider did not clear all of the grades, and the third rider, who is somewhat stronger than me, had a tough time. If I had been on my non E-bike, I would have had a bad day... I used 87 Watt Hours, out of 100 WH available in my new Zippy 4S 8AH pack. I carried a spare (not used) 5.8AH in the fanny pack. I'm liking this light weight setup a lot

"lack of PAS, along with advocacy for removing the throttle in favor of an on/off button! is that a joke?"
1. I certainly didn't advocate for removal of the throttle in favor of a button. The individual who did, however, made some interesting points...
2. I asked for a discussion in my ES thread re PAS vs Throttle vs other. There were many interesting viewpoints.
3. The throttle is working well for me at the moment. Before the discussion on ES, I did not feel the need for PAS. Now, I'm thinking about it.

"no means of locating the chain in the proper plane, along with use of a chain not designed to tolerate it"
1. The chain is located in the proper plane within .010".
2. "Means of location"" is the motor mount...

"no chain tensioner"
1. Tried it, don't need it. You can see the leftover mounting holes...

"lack of freewheel meaning the motor creates drag while pedaling, mitigated by how small and ineffectual the motor is"
1. the motor is actually pretty effectual, as shown by MY KNEE DOESN'T HURT!
2. "lack of freewheel" was actually the big surprise of the build. I originally built it WITH a freewheel for the reasons you give, then I tried it without a freewheel. I was actually shocked by how freely it pedaled. The motor absorbs less than 10 watts (BLDC motors spin nice!). For comparison, the bike came with a Kenda Nevegal on the back. I hated that tire, as it was very draggy. It (and other draggy tires) felt far more draggy than the motor.

"9T cog wears like cheese, as evidenced in the ES thread already"
1. Yup, 700 miles on a $7 sprocket. I'm crying in my soup...
2. I got less miles out of a very pricy Ti XTR cogset.
3. I got less miles out of an aluminum 42T rear cog.
4. Chain and 9T cog wear are on par with bike chain wear. Shock!


Hey Craig - If you are in the San Jose area, lets do a ride. Seriously. (or anyone else who is curious...) You can try out my E-Bike, and I'll take my Trance. PM me. I think you might be surprised...

Here is a ride report from someone else:

My impression of FZBob's system

Weight:
I was shocked by how light this system was. When picking up the bike it feels just like a regular mountain bike.
The bike rides and respond just like a regular mtb. I am not aware of any commercial mtb ebike that can match this in weight.

Assist:
When ridding without assist, I could not feel much resistance from the motor.
Adding motor assist by feathering the throttle felt very natural. I never felt the motor "kicking in" like some middrive systems I have tried in the past. I suspect this could be the programming or the single stage reduction.

Freewheel function: present and not present
You can freewheel just fine as the resistance from the motor is not noticeable but you cannot freewheel when the motor is on. This is something I am not used to and may be something to consider for technical mtb riders who need to have pedals in certain positions during the ride.

What about the noise:
Noise from the motor is not noticeable at low levels of assist (I think below 100W) and become more noticeable as the assist level and RPM goes up. I think slightly more than a BOSCH mid drive but I would need to test side by side to elaborate more.
I ride a completely silent Leaf hubmotor using the PHASE runner and I find the noise of this system not bothersome.

Overall, I think this system is terrific for those looking for a lightweight and low power (250W or less ) system to add on to an existing mtb or any bike for that matter without changing the characteristics of that bike.

My request:
Please consider adding torque sensing via bottom bracket. Having both the throttle and torque sensor can make this system even better.
 

·
Registered
Joined
·
65 Posts
FZ, you should try to patent something like this, it has way more potential than you even realize. If you or someone else can get it to the point where the chain / motor / battery can be removed within 1-2 minutes, it would be a great alternative to a mid-drive because you remove those three components and you have a perfectly normal bike that just has a large chainring on the other side. And then riders, instead of having to shuttle with two trucks, can simply ride back up faster after they are done with a long downhill session. They ride down without the components and then slap them on at the bottom. These would sell like hotcakes because they are light, cheap, and easy to take off and put in a pack.


What I'd personally like to do (and even sell on Amazon, etc.) if I had more mechanical skills:

1. Chain guard on large chainring
2. Remote wireless throttle or push button on/off for watts, no wires from the handlebar, only from/to the battery
3. Chain that's easy to remove, with a user-friendly missing link that you push in and quickly break & put in pack
4. Cassette-based 0.5 lb LiPo battery, plugged in securely to some type of housing attached to one of the tubes. I'm calculating about 2.5 miles worth of battery uphill at 250W, is that in the ballpark? The kit could come with maybe 5-6 of these batteries that you simply plug in to the housing (kind of like printer ink) and then connect the battery wire to the motor in seconds
5. Kit bag with all components, extra batteries, motor, chain, any screwdrivers, etc. for attaching at the bottom of the mountain


If someone could make a kit like that for around $250 that weighed under 10 lbs with the extra batteries...
Thanks for the compliment! I already have sufficient patents, and don't want to hassle with it.... $10K to 30K and 1-3 years... Sounds like work...

A 1/2 lb battery will give you about 30 watt hours, so at 150 watts of assist, about 12 minutes...

By the way, you don't need to break the chain, it lifts off in a loop as soon as the motor is loosened.

I think for your use case, I would consider just leaving the components on the bike, rather than on your back, unless you can hand them off at the top of the hill...
 

·
Registered
Joined
·
65 Posts
Craig - you seem to have a lot of rage. You are no longer invited to come for a ride with me... Have a nice life...
 

·
Premium Member
Joined
·
7,491 Posts
I think very lightweight 100w systems are what most people actually *need* who have, like FZBob, some minor ailment that makes riding painful or difficult. That's actually quite a bit of extra power.

600w/much heavier bikes like a Levo are a totally different beast obviously and if that's what you want (to haul ass) that's great. I think if you are looking for as much of a mountain bike-like experience as possible, limiting the wattage and weight as much as possible makes a ton of sense.

No comment on the safety or fire issues, but I think this thread demonstrates both the potential and potential downsides of DIY and kit (ie Luna) e-bikes, which is something that I'm sure we'll see more and more of.

-Walt
 

·
Premium Member
Joined
·
7,491 Posts
Sure, sure. My point is that the current bikes are overpowered (probably by at least 200%) if the goal is just to get folks with health problems back up to even with able bodied riders. Bikes like the Levo (as anyone who has ridden one can attest) are a VERY different experience than a conventional mountain bike. That's totally fine with me, actually. I just think they should be managed as their own entities.

-Walt
 

·
Registered
Joined
·
254 Posts
Once again LIFT-MTB:

https://www.lift-mtb.com/accueil-faq-english/

Good quality battery cells with a controller built into the battery pack are safe, work great and cost so much less than manufacturer proprietary batteries (I have 3, never had an issue).

Put a similar motor on a Niner Jet 9 and it works great. Battery pack comes off with the Velcro of the under top tube frame bag. Motor comes off with 4 allen screws and a chain link.
 
1 - 20 of 43 Posts
Top