BBDrive

So here's some information about me and why I decided to build my E-bike like I did.

About 2 years ago a now-friend moved in next Door, He had been building electric bicycles with a friend of his. They both had some friction drive setups built up with 750-900 watt Unite Motors. I checked them out and rode them and really liked the FUN factor, knew I wanted one.

But didn't like the friction drives at all, you couldn't pedal easily, no easy way to disengage the motor, no freewheeling. Yet even with the friction drive and the Inefficient Unite Brushed motors he got 10 Miles out of 36V @ 12AH SLA...
I also rode a few hub motors and was less than impressed with the acceleration, once you got them rolling they are cool. and also the mileage they would provide with the same batteries.

So after researching everything I could find online cause I KNEW I wanted to drive the Bottom bracket, take advantage of the freewheel on the wheel, and the chain, and the gears. I eventually found out about IPS Cranks. And saw some videos of KNoxie with a Kolmorgen motor, seeing those on E-bay cheap I bought a case, and my project began.

I ordered an IPS crank which is for the rear person on a Tandem so they don't have to pedal if they don't want to, the chainrings freewheel independant of the pedals.

Then went to work building version 1.0 as seen below:

Version 1.0:::


Frame: Trek 8000, Nice made in USA bike
Crank Lasco IPS (IPS Standing for Insolent Piece of ****, way too much play!!!) With machined adapter and 90 tooth gear.
Motor: 24V Kolmorgen with internal controller,
Batteries: 2-12v 20AH SLA's from Batteryspace (or someplace like that)
Throttle: 5K pot (see handlebars)
Brakes : Cantilevers
Tires, old knobbies.

Gears:

This configuration with a 9 tooth motor gear and a 90 tooth crank gear along with a 24 tooth chainring resulted in a top speed of ~24 mph in top gear. However whenever you wanted to pedal it was rather ******** with only the 24 tooth front chainring.... I also didn't like my motor mount so I revised...

Top Speed ~24 w/ knobbies
Range never fully tested the range Maybe only rode it about 7-9 debug miles while I decided on rev 1.1.
Acceleration, AWESOME



Here is some Info and pictures of V1.1 E-bike

Anyway Here's some info about the Bike rev 1.1 :
1.1:::

Frame: Trek 4300, cheap crappy china made bike (still decent)
Crank Lasco IPS (IPS Standing for Insolent Piece of ****, way too much play!!!) With machined adapter and 90 tooth gear.
Motor: 24V Kolmorgen with internal controller,
Batteries: 2-12v 20AH SLA's from Batteryspace (or something)
Throttle: Magura 5k
Horn:Airzounds
Brakes : V-brakes
Tires, High pressure road tires, @ 85-100psi

Gear:
This bike has a lashout gearhead, 4.7-1 ratio then goes from a 17 toothfreewheeling motor gear to a 90 tooth chainring resulting in a cadence/BB Max RPM of about 112.
This version has a chain tensioner and a little different motor mount utilizing the water bottle holder bolts. This has a 26, 39 and 52 tooth chainring on the crank, But I always leave it in middle except for over 35mph (downhills). This results in a range of speeds from 9mph to 30.6 (theoretically) more realistically a top speed of ~25mph on the flats without wind.

I have been riding this version to work for a couple months, haven't riden every day but I have riden ~500 miles. I average anywhere from 23mph to ~25 mph depending on wind, and with a tailwind today I averaged ~26 on the way there and about 22 on the way back with the headwind in the afternoon. My Commute is 9 Miles each way, I charge at work but I can ride ~15 miles on one charge (I never really drained them either), and can make the round trip easy with a little pedalling.

The bike makes for a GREAT pedaler, it's really easy to pedal and you can easily pedal up to ~32 on flats, and even a little faster if you want to sweat, I am not much for pedalling I ussually just ride without pedaling unless I am in a hurry.

The acceleration is sweet as is the delivery of power and ability to upshift while under power very smoothly!! Downshifting Is actually smooth also.... I thought the cassette would be rough but it has turned out to be very smooth shifting, nice shimano components.

Here are some pictures of E-bike:Version 1.1



I will be posting some pictures before the end of the weekend as I am installing a new rear rack, red panniers, moving the batteries into those. By Next weekend I will be receiving my drainbrain and a 48V 35A crystalite controller to wire up to my kolmorgen and see what 36 and 48V feel like...

I will be testing my Setup with the DB @ 24V, 36V and 48V to see the WH/Mile that i am getting at each voltage. I know the internal controllers SUCK on these kolmorgens, I have gone through like 3 this is my 4th !!! (one was damaged in an auto vs E-bike accident)

I feel that this is a pretty good Efficient setup; it's fast for the amount of power (300-400 W) and it goes all 9 miles without loosing any top speed to speak of, maybe down to 21-23 from 23-25 after 9 miles.


Comments are welcome,

PDXJeff

https://www.denalicycles.com/

Have you checked these out? They're more like a motorcycle than a bicycle, but you may be interested in their motor and drivetrain design. I got to ride one once, it was very fun.

BBDrive

Yeah I have checked out a bunch of those electro-cycles and they aren't even close toa bicycle, mine rides like a bicycle, my entire drivetrain weights ~7lbs... If I wasn't running SLA batteries I would have a light bike..
I am in Corvallis Oregon so I am fairly close to you, what do you ride?

Jaleel Johanson

^ You've definitely headed in the right direction! Next, I'd clean up the battery mounting and consider throwing a little oil on the original chain.

BBDrive

I just got done isntalling a new rack for a new battery mounting system. The pictures you are looking at with the rusty chain are from like May, it is a different bicycle from my V1.1 commuter bicycle. That chain was just used for like a week of debug before deciding to move on to utilizing the gearhead in a new design. The commuter (grey) bicycle has a brand new chain on it in the pics, it is a few months old now.

It still isn't as finely tuned up as it could be because I just swapped the rear wheel with a new one after a lady hit me and bent the wheel to where it wasn't trueable. And the new wheel needs to be trued still, and I just want to get it a general tune-up. I am not as much of a bicycle mechanic as I am just a mechanic, I do my own bicycle work like swapping wheels and cassettes and installing brakes, but think I should leave the bicycle tuning (truing) stuff to guys who do it all day every day.

I have been contemplating switching to an internally geared hub, that would be the next logical step with a single speed front chainring, eliminating derailers altogether! But the cassette just shifts so finely under power that unless I am wearing it out in a year from the increased stress from the motor I will probably stick with it for a while.

What is really surprising is that since the motor delivers such a smooth power, it seems to shift better under the motor's power than under pedaling with the peaky delivery of power.

I do so much love that I can go 25 MPH without pedalling and with a 400w Motor, along with the distance I am getting I think I have pretty decent efficiency I can't wait to see my drainbrain readings.

PDXJeff

BBDrive, I ride a regular bicycle. When I lived in southern Oregon I got to ride a Denali and was mostly impressed with how quickly it accelerated. That's why I mentioned it.

adamtki

I like how you mounted the motor. It looks better than the motor from cyclone-usa.

If you can drive the inner chainwheel of a 3 ring crankset, you can even cover part of the motor chain and motor gear. That would make for a cleaner looking drive train.

BBDrive

The problem with driving on the inside is that with the side of the gear required, when you put it on the inside it forces you to move the rest of the crank outward away from the bike a bunch.

Like I said I hardly ever shift the front derailer and will be doing a single chainring crank soon..

EvilV

Is it possible that some part of your clothing or even your own skin could get caught by that chain system and pull you in there? Maybe you have a chain guard system. You'd not want to get dragged into that sprocket and chain with the motor running.

BBDrive

I've riden it ~600 miles with loose pants without any issue at all.

Forgot to update my original post but the batteries are 24V @20ah not 36V.

BBDrive

Latest Pictures showing new battery mounting bags and rear rack.

sherpa93

BBDrive very nice job! Some questions if you have some time. Your motor is clockwise rotation facing shaft but the kolmorgans on ebay are CCW rotaters. Does it matter? What is the happy efficient rpm for this motor at 24V and 18-20 mph? Have you experimented with 36V? Can kolmorgan controller handle 36V? Thanks!

Ornery

Looks like a well executed design so far, but you mention in another forum that you want to have a hubgeared drive system next time around? Sheesh, after all you've invested in this?

EbikeHawaii

Some live and learn by there expearences and expearences of others. Some people never learn.

sygyzy

Cool bike. What happens when you peddle? Does the motor immediately disengage and you have to catch up with the rpm's?

BBDrive

I bought a lot of 8 CCW motors off E-bay for ~210 and have reversed them one at a time, the only tricky part of this is that unless you are VERY tidy with the splices for the phase wires they will push against the board holding the hall sensors and it eventually overheats the motor and cooks it. I am on motor 4 now, but one I messed up in reversal and another got munched in a car VS e-bike battle.. the car won

One motor kicked the can randomly (controller failure), the efficient no load RPM is 2800 with the planetary gear reduction and 17-90 ratio combined I am spinning ~90-110 RPM at the BB.

I have heard that the controllers won't take more than 29V and I haven't tried one at 36V, however I do now have a crystallyte 48V controller w/ drainbrain (cycleanalyst) that I will be installing and testing at 24, 36, and 48 V for efficiency measurements.

Sheesh, You sound like my WIFE!! lol yes I do have a bit invested in this one but all would be transferable to other bikes plus why have one e-bike when you can have 2??

I Will try an internal hub dualdrive setup in the future but I am very happy with this setup I have riden over 700 miles in the last few months since building it.

I will make some changes to this one before I go to a different drive system, I plan on installing a rear geared SA 8 speed w/ disc brake hub on this bike along with a new crank with a single chainring and single speed chain.

The derailure system works very well shifting under power and all; however the chainrings are alloy and inspecting the middle one (which I use almost exclusively) it is very "polished" (worn) after only 700 miles from the chain angle with shifting under power constantly.

And some people never change; ie: constantly posting about how awesome your design is but never posting to help other build one, or helping others with suppliers for mythical 100% efficiency motors...
Sorry Randy, I have found you often have valid imput but it is totally offset with all the negative postings you make with no point...are you saying I never learn or just throwing in a superfluous comment??


When you pedal without the motor it is like pedaling a heavy bike, the motor chain moves but due to the freewheel in the gearhead the motor doesn't spin or introduce resistance.

The controller is setup with a throttle so the motor engages as I throttle, the pedals freewheel from the crank so that you can run the motor without having to pedal. However when you DO pedal it is an odd but incredible feeling as I can easily pedal up to 28mph (with effort up to 32+ mph) at a great acceleration rate, I can leave a light and cars not catch up or pass me for ~1/4 to 1/2 mile in a 45 MPH zone...

Anyway I am going to be trying it at different voltages this week and finding out how much fun it is with more powahh!!! ha ha ha ha....

Also really excited to find out about the efficiency.

Regards, thanks for the kind words!!

Lowell_

I like the layout of your drivetrain, and the fact that it's adaptable to pretty much any double diamond frame. I too am interested in seeing how your Wh/km numbers come out at different speeds and voltages. The CycleAnalyst is a real treat to use compared to other methods.