Ebike Lite

[cannonball2]

More parts inbound this week. Am trying to stay carbon as much as possible. There are Chinese carbon bits available fairly cheap. Bought a seat post and handle bars/stem. This build is very light and I wince every time I add heavy stuff to it.

Will be running the CA3 and the Grinfinon controller that is good for up to 72v, but I will probably settle at 63v initially. I can swap between a 3 or 4cell pack to get either 63v or 67v. Lipos at Hobby King are fairly cheap now, so I bought several combinations.

Thanks for your help LC!

 

[Lungcookie]

No problem, happy to help.

That bike looks like it was made for batteries.

I thought I would add too that I am not to sure you get regen on a geared hub as it disengages with a clutch. At least that's is how this MAC motor is.

Where as a direct drive motor is always on/resisting so to speak.

Got me looking at China carbon parts...that's the way to buy, direct.

Have fun!

 

[wheelbender6]

The Trek STP is one of my favorite mountain bikes. I have a KHS soft tail mountain bike (no suspension pivot - The chain stays flex). I doubt that I will ever motorize my KHS. I enjoy pedaling the trails on it.

 

[cannonball2]

Thanks for the input WB6. Nice to know its a good frame. The search format dictated a triangle type frame for battery placement on the down tube. This one fit the specs and was at a good price so I went with it. Think its gonna make a nice build.

 

[cannonball2]

Got the handlebars and seat post. The bars weigh 4.2oz the post 6.4. Wow! USPS lost the full carbon stem. They say they delivered it but it wasn't in the box with the rest of the parts, Oh well.

The bike weighs an amazing 18 lbs as it sits. Its missing the BB, cranks and pedals, chain and battery tray maybe 3more lbs? The battery pack weighs 4.4 lbs Be really nice if it came in around 27 lbs or less.

The controller mounted to the seat post bottle mount and the batteries will be on the down tube. Fairly compact. The wiring should be basically invisible when finished. One throttle wire goes to the CA3. One wire from the CA3 to the controller, the motor wiring plugs in under the controller as will the batteries.

Sorry about the pics its raining outside and the camera takes lousy indoor shots. You get the idea though.

 

[kevyleven007]

I've never seen a frame like that before. What's that thing at the top of the seat stay? Never mind I double checked the first page. So, it IS a shock. I wasn't sure. That's crazy how light that thing is. Looks pretty awesome.

 

[wheelbender6]

Here is a little softail info from wikipedia. The soft tail has a shock absorber on the rear, but no mechanical suspension pivot. Therefore, suspension travel is limited to an inch or so.
"A soft tail (also softail) relies on the flexing of the chainstays of a regular diamond frame to create suspension travel, sometimes incorporating a specific flexing member within the chainstays. A shock absorber (or elastomer) is placed in line with the seat stays to allow the chainstays to move up and down, and for shock absorption. As the suspension moves through its travel the seat stay and shock absorber move out of alignment. This misalignment creates a mechanical lever for suspension forces, causing torque on the joint between chain- and seatstays. This is an inherent structural disadvantage of the soft tail design and severely limits the amount of travel possible, typically around 1 to 2 inches. Soft tails have few moving parts and few pivot points making them simple and requiring little maintenance. Some notable examples include the KHS Team Soft Tail, Trek STP and the Moots YBB. Some bikes (such as the Cannondale Scapel, Yeti ASR Carbon and older Yeti bikes) use a four-bar suspension design where one of the pivots is replaced by a flexing link."

 

[cannonball2]

Thanks K007!

Great explanation WB6. I never realized this type frame existed until I bought this one. It was said by the seller that the bike rides/handles like a rigid frame when off the seat standing on the pedals, but has some suspension when on the seat.

Havent had much time to work on it, but did get the battery tray roughed out. The heavy duty(1/4" thick) Home Depot yard stick seemed to measure up to the job of side stays-hehe. Once the wiring is sorted should be a fairly clean install. The bike is still pleasingly light even with the batteries(67v) the 63v is a bit lighter still. The bike/rider may come in at around 200lbs. I'm 170 of it.

 

[kevyleven007]

30 lbs for an ebike! Heck a regular steel frame bike weighs more than that!

 

[Pablo]

I like that frame.

 

[cannonball2]

It has come in heavier than I had hoped for. I'm weighing on bath room scales which is not the best method. I did however "calibrate" them with an unopened 16lb bag of dog food, the weight of the bag is in there also. Should be in the close ball park. The bike in its present state of assembly(less chain, BB, and pedal cranks, but with batteries) weighs 33lbs. The BB has yet to arrive but the cranks and chain weight just under 4lbs on my wifes kitchen scale, so lets just add another 6lbs, or 39lbs total. As it is when you pick it up it feels super light. I guess I need to loose 10lbs to hit my original target weight--right!

Finalized the wiring last night. About 2hrs of messing with tiny wires, soldering, and shrink tubing. The throttle is permanently married to the CA3, they will come off the bike together if necessary. The rear wheel/motor has plugs in the usual fashion to allow wheel/tire removal. All in all its minimal wiring. Every thing works as it should. Will have to get with the CA to change to MPH from KMH. I don't know much about the CA yet, but was surprised to discover if I plugged in only two batteries it apparently reset the voltage range to 30v and the bike would operate at that voltage instead of being shut out with the LVC. If that is so any number of batteries can be run with in the limits of the controller. Cool!

The switch on the controller is a total cut which means you can leave the batteries hooked up with out drain. I wouldn't leave em long term bit its nice for stopping for a while. Gonna ride it this am with no pedals!

 

[Lungcookie]

Looking good CB2.

Still pretty lite.
I thought I was doing good at 43-44lbs. no battery. Sheesh.

One thing about lite weight, it is usually the opposite of heavy duty.
So you have to consider the trade off.
I have seem some 18-20lbs mtb bikes but I don't know how long they would last.
http://www.pinkbike.com/buysell/1800399/
Maybe a season?

I have big paint chips and little dings in the Aluminum down tube from the front tire shooting gravel projectiles, sounds like a bb gun shoots the bike.
That can't be good for carbon.

The CA is easy to open, 4 screws, just 3 solder points for the throttle, can pop that throttle off in a couple minutes.

Did you use that Magura throttle?
May have to do some calibration, hi/low volt range.(to get the dead spots out at the top and bottom of the throttle range).
Also add a resistor.

Thats handy with the LVC, the CA3 just over-rides it all, nice.

/cheers

 

[cannonball2]

Thanks for all the help LC!

Parts all showed up and the bike is basically finished. Its a pleasure to pedal as a bike not only because of no motor drag but its just a nice riding bike!

Me and the CA3 parted company this pm over throttle issues. Will have another go at it later with a Magura.

As for now its back running the old Infinon 48v controller on 64v and it works perfectly. The controller is fixed at 20amps which makes 1280w out of the 350w motor. It really doesn't seem to care neither got very warm. Acceleration is brisk to say the least and the top end has to be in the very high 20s. The bike is the star of the show. The combination of the frame/soft tail and the Hookworms makes a great handling bike that really rides great. The roads on the island are sand/gravel/old pavement- rough even in a car yet this thing rides pretty smooth. The bike begs to be ridden full bore.

The CA3 is a cool piece and will get back with it. Was mainly wanting to get the bike up and running so I can see what doubling the voltage(close) and tripling the wattage will do to the little motor.

Cool bike in the link btw. I think the carbon frames are pretty long lasting. I would suspect the wheels would be the failure point.

 

[kevyleven007]

Looks great. Hope you don't mind me asking but how much $ you got in it ? Total cost to build this bad boy?

 

[cannonball2]

Looks great. Hope you don't mind me asking but how much $ you got in it ? Total cost to build this bad boy?

Good question. Will hit the high points. Some things are not easy to value such as used parts that have been on several builds, so probably wont include them.

Motor kit $189 shipped
Frame with new shock $150 shipped
Hookworms and tubes about $100 shipped
Carbon handlebars $22 shipped
Carbon seat tube $31 shipped
Batteries(5) $109 shipped(close out sale)
Used front wheel/brake $50 shipped
Bottom bracket 12.95shipped
Chain $8
Electrical misc $10
Chain idler and freewheel$30 shipped
Basically 711.95. Things like the seat, rear brakes, cables, etc. came from the junk box. I'm not including the CA3/Grinfinon Controller as its above the basic build. I believe the common R/C wattmeter would work well in a basic build and only costs $10/15. I have one on the Schwinn.

Had been wanting to do a carbon frame build a long time and was looking at new frames from China in the $3-400 range as well as used frames. This one seemed a good deal. Its amazing how quickly a build adds up, but after very limited riding of this one I can tell its going to be all I wanted.
I'm down to two Ebikes now this one and the Schwinn step thru cruiser which I really love.

 

[Lungcookie]

Good work.
You always turn out a nice finished machine.
Tires look great on that bike.
...under a grand, wow.

I PMed you about the CA3.

Also I have zero carbon experience, so any comment I made about durability is an assumption on my part.

I bet the Hookworms don't throw much gravel.
This front tire I am running now shoots rocks like a gun.
It really hooks up but its like running mudders on your truck.

 

[cannonball2]

Thanks LC!

I'm no expert on carbon either. From looking at used frames it seems that they are pretty durable and take the dings and scrapes in stride, up to a point I guess. I assume the frames are repairable using the proper methods. Seems like one would try to repair one of those $4500 frames!

The Hookworms probably are the contributing factor on this bikes ride. The rigid steel frame Schwinn rides nearly as well. I don't carry a lot of psi, around 30. Rides great there and seem to roll good as well. And no they are not throwers of road debris.

I rode thru a full charge(4.2/cell,67v) this am. Took it down to the pavement and strapped on the Garmin. Briefly hit 33mph on the peak voltage but soon dropped to a max of around 27/28. The little motor seems none the worse off. Sounds a bit like a turbo as the rpms get extreme. I baby/pedal it til around 10mph then nail it! Expected the controller to blow with 63v caps. I paralleled 6 extra caps to the controller a long time ago and maybe this is why it hasn't blown yet. Soon I bet.

I'm becoming like you LC a WOT rider! Too much fun.!

 

[cannonball2]

I ordered a pair of 6s 10ah lipos like LC is running. Will use these as travel/distance batteries. This pair will come off charge @ 50.4v to operate the 48v system on the bike in a stock manner. If I find this too sedate will couple a pair of 3s 5ah(10ah total) for a off charge voltage of 63v. The idea of cruising on only two 10ah packs is pretty cool.

Neat thing about a geared motor especially on pavement is that it will coast freely when off throttle. Here in the flats you can get the bike up to speed then just add a pulse of power occasionally to keep it rolling. Havent figured out if this is more efficient but it will roll a long way between pulses.

Though I have many ICE bikes, Ebikes are in a world of their own and I find much easier to experiment with and modify, and so far have been totally reliable.

This one is a great test bed.

 

[cannonball2]

Got the 10AH packs. Changed the XT90 connectors to XT60 to be compatible with the bikes wiring. Overall these two packs are smaller than the four 5AH packs but also lack the voltage(50.4v vs 67v off charge). Still the bike will be plenty peppy with them.

Well I can attest that the little watt meters rating of 60v is the ceiling as 61.3v took it out. Ordered another for the 50.4v system. Its modular so it can be removed for the higher voltage systems. When the CA3 is reinstalled it will handle all the voltages.

The pack in the pic is the 63v pack using three 4s and one 3s pack instead of four 4s. This system is really modular.

 

[cannonball2]

So it was easier just to make a new battery tray than a slide in adapter. Still needs it standard coat of flat black.Takes only a minute to change between the two systems. The bike is some what lighter also. Didn't top off the packs but ran as received at 70%(around 46v).

Got a chance to do a quick ride in between rain showers. The bike was a bit less snappier on acceleration, but still has a good top end. Of course it will never match the 63/67v packs in this area, but its still plenty quick and the range is double.

I like the simplicity of only having to parallel two packs with less wiring and connectors. These packs are a lot of voltage/amperage for the money.