AM dual motor = bafang middrive + rear hub motor

[John Bozi]

So many options Sean.

The stuff that my penny chopper fails I highly doubt will be conquered on even a cross country geometry bike with an aft generation 5000 of what they offer now. Starting from a dead stop in my opinion on these sections could only be done on a heavy dirt bike = the weight being very important and then a proportional amount of power to deal with that weight and basically it would leave huge holes in the ground to do it.

Even on an LMX the french guy he would be tipping back....

so mid drive would be great but again stick it on a cool down hill bike to enjoy other parts of the ride and you again have the wrong geometry to get up the steep mountains and there are more powerful set ups or custom jobs to explore ....

aft is not ruled out im just not sold because I cant try one.

 

[Sean9002]

So many options Sean.

The stuff that my penny chopper fails I highly doubt will be conquered on even a cross country geometry bike with an aft generation 5000 of what they offer now. Starting from a dead stop in my opinion on these sections could only be done on a heavy dirt bike = the weight being very important and then a proportional amount of power to deal with that weight and basically it would leave huge holes in the ground to do it.

Even on an LMX the french guy he would be tipping back....

so mid drive would be great but again stick it on a cool down hill bike to enjoy other parts of the ride and you again have the wrong geometry to get up the steep mountains and there are more powerful set ups or custom jobs to explore ....

aft is not ruled out im just not sold because I cant try one.

True john, its always deceptive looking at a hill on a video. Until you 'feel' how steep it is, you never know. A hill like that would punish all but the upper echelon on Ebikes. After riding downhill since I was 16 I can attest to the fact that downhill bikes are that for a reason. The geometry only really suits one thing...going downhill. The trend towards freeride style frames in recent years has changed all of this. the enduro scene is taking off and those long travel frames, with cycling geometry, are becoming cheaper. Although having said that your HASA frame is probably not all that dissimilar to a Freeride frame.

Dual hub motors?
Would help with the front lifting having the extra weight up there, not to mention a lot of torque.

 

[John Bozi]

So many options Sean.

The stuff that my penny chopper fails I highly doubt will be conquered on even a cross country geometry bike with an aft generation 5000 of what they offer now. Starting from a dead stop in my opinion on these sections could only be done on a heavy dirt bike = the weight being very important and then a proportional amount of power to deal with that weight and basically it would leave huge holes in the ground to do it.

Even on an LMX the french guy he would be tipping back....

so mid drive would be great but again stick it on a cool down hill bike to enjoy other parts of the ride and you again have the wrong geometry to get up the steep mountains and there are more powerful set ups or custom jobs to explore ....

aft is not ruled out im just not sold because I cant try one.

True john, its always deceptive looking at a hill on a video. Until you 'feel' how steep it is, you never know. A hill like that would punish all but the upper echelon on Ebikes. After riding downhill since I was 16 I can attest to the fact that downhill bikes are that for a reason. The geometry only really suits one thing...going downhill. The trend towards freeride style frames in recent years has changed all of this. the enduro scene is taking off and those long travel frames, with cycling geometry, are becoming cheaper. Although having said that your HASA frame is probably not all that dissimilar to a Freeride frame.

Dual hub motors?
Would help with the front lifting having the extra weight up there, not to mention a lot of torque.

dual has crossed my mind but I see more drawbacks than benefits.

+ front weight (no wheeling)
+ 1 motor fails have a back up

- front weight - you see a bigger rock or branch suddenly and can't lift up before face planting
- fork fatigue (or no suspension) or maybe a motorcycle fork could handle it.
- more weight (unless bought two light ddrives)
- more wiring
- more drag

So the problem is this: we all enjoy flat and downhill riding - changing the geometry to uphill - ruins the downhill and high speed flats.

my commuter is a regular hardtail el cheapo, going fast on that for one reason is scary because of the head angle, even on my carbon hardtail I really have to concentrate to get my ass behind the seat near the tyre going down steep parts to feel safe against summersaulting forward and losing my teeth...
Going down or super fast flat/medium up hill on my penny chopper is awesome hitting a hole or bump... the larger front makes it over, and the back is never as scary as the front....

It is funny how we all love lighter bikes, but to some degree the heavy batteries actually smoothe out and absorb the ride and the wheelie tendency....

Makes me wonder if I really want this to handle more like a bicycle...

All I know is it's time to buy my next set of batteries and create a under the down tube tough battery box.....
and let's not forget that even though we build a bike perfect for something like off road it should still be great at multi purpose things like caning the suburb hills with high torque acceleration silently not lifting the ears of the neighborhood dogs....

 

[John Bozi]

spent a bit of time editing a video just to find post render that my frame rate was wrong! You can't notice that in editing as the preview is low quality... ah well will have to record it again next sunny day.

remember must be 120 fps (this was jittering at 60 fps......

[youtube]u9qPGbjosaY[/youtube]

 

[drew12345]

Nice vid john! I see you got some air there.

 

[John Bozi]

Went up the mountain ready to make a video but sometimes I just couldn't be 123456 trying. Riding is so much fun and the videos that I like to watch are not what I enjoy riding, so just went up there and hammered it.

1. I bought a on speacial heat gun and did some pvc folding of the old drain pipe I had. It's not perfect width but I love this, and will spend some money on plastic welding stuff. I feel much better about having velcro attached batteries now

2. REGEN. Heat has always been a big one with me, and now that I know my trails I can make some wise decisions. If I know I will be facing overheating in the next 10 minutes then I just use disk brake, if I know I want a beer and smoke stop then I just use regen. It's simple. If it's just normal on road riding everything is regen....

It made a big difference today with not one stop needed but I forced one to do it.

3. Riding bike realistic stuff, my bike just hammered up the hills, these are old trails back with 26" I was struggling with and constantly overheating on, now I just power it through even jumps and monos all the way up the mountain. Yeah dont need all this power most of the time but there are moments where enough power means less heat... Its a strange crossover point. I have enough amps to destroy the parts which require overheating to get through...

4. time to swap out the rear tyre if I want secure riding, I was fish tailing like crazy especially on hard throttle...
but then again I love the smoothe tyre on road.... more efficient and fast.

5. I tried to go do some single track but just kept thinking how boring it was to be forced to go slow... maybe single track is just not me anymore?

 

[John Bozi]

Was going to wait for this car but just said stuff it and flew up the mountain anyway. Trialled a rear mount for future rides with a buddy who might have forward facing camera. Would be good to get the footage of both directions.
Notice the sound which is mostly through vibration, not air.
[youtube]QzkNZVdH-4M[/youtube]
so spotted some short track Ive never been on as I usually fly up the mountain in the other direction.
[youtube]ZebWvgXb6tI[/youtube]
and then got a bit lost from the new point.
[youtube]8UFCEIojtUI[/youtube]

waiting for the last video to process

where I climb up a long sing track

overall these are long boring videos I just uploaded for the hell of it. The rear view is really good if you have a riding buddy behind you.... Newb can you see this?

 

[John Bozi]

going up the berms is just as much fun as going down them. surprised the motor was no where near overheating going up the single trail because it was so gradual.

final part of the ride up

[youtube]qshV83W-P5g[/youtube]

 

[John Bozi]

I've got my ca display on amps not watts, because I have a newish controller I want to sus out what its doing.

My max amps are often higher these days, not sure why they have gone up from the previous 62 something to 65... Must be doing the hard core trips off road around the dam etc.... for sure am pulling up slopes the motor used to stall on before. I just usually take a smoke break before climbing and the 20 degree C increase on a pass is no problem. Lay off the regen a bit when I know they're coming pedal a little more and heat doesn't bother me. A couple of breaks is a nice way to enjoy the nature and let my body relax from all the jolts too. Not a spring chicken anymore....

Even though I'm pretty happy with my battery set up @ the moment I like tinkering and opening up new spaces.

I was telling the neighbor about what I needed and he pulled out and gave me a big aluminium something tray. It's bit thicker and tougher than the propellor plate I bought and has a couple of folds in it that I can work with.

Today I finally decided to do a cut on that alu. I cut a strip 13cm wide, after ages thinking about current batteries and future batteries decided that was pretty much the optimal for under the down tube.

So currently I got this [ looking kind of shape but it is too long and the folded part that will be near the front tyre is too long too. Will probably do one fold in it so it is about 30cm long so [ will have one more bend looking like a C...

Basically I see that I can fit a max. of 4 x 6s batteries under there. If there is a tyre clearance issue after mounting the base plate with batteries I could possibly drop down to a 24" front wheel. Don't really want to that because ground clearance problems would increase...

Basically I would just use hose clamps so that I cant easily remove it if I want and I have bottle screw holes underneath to stop it from wanting to slide down the down tube.

For now I would just velcro the batteries to the base and make a cover, eventually abs to protect the batteries against dirt/water.

I really like the way I have the batteries now, so this would be just adding to where they could mount or even be able to carry 24s1p or 12s 2p more than the capacity now. I doubt I try to link everything into one unit, just have separate battery packs to extend rides.

Thinking of the HD 6s series now, they are

Specs:
Minimum Capacity: 5000mAh
Configuration: 6S1P / 22.2V / 6Cell
Constant Discharge: 60C
Peak Discharge (10sec): 120C
Pack Weight: 882g
Pack Size: 143 x 59 x 50mm
Charge Plug: JST-XH
Discharge Plug: 5.5mm Bullet-connector

I like the length which I could use as my current ones. (I can't use longer batteries under the seat or in the mtb bike cases )
they are 60c meaning I could probably use them 1p if I was careful

and 1p 4 batteries would rock for just having a blast

I really like 4 6s as my set up as it is suitable for charging with my current set up.

thats the thoughts for today....

 

[John Bozi]

[youtube]AyvBFCqsmjc[/youtube]

 

[drew12345]

I like how you post a lot videos. This is another great one.

 

[John Bozi]

Thanks drew, It hard to find good songs or anything related to ebikes anyway...

I finally hit the buy button on some bits and pieces for plastic welding.
I bought this bit - which I hope will fit my cheap gun.

And then this is the speed nozzle that push the rods through.

$23 delivered for both. Will take probably a month... but no rush. To be honest it might end up just another bit of unusable junk I've bought because of ebiking. I think it will be a bit of fun if nothing comes of it. The rods and plastic sheets aren't cheap either. (probably cheaper to buy actually made boxes and then cut them apart and see if I can work with the off cuts) Ah well I like the idea of custom battery protection sizes for now and hope this path will pay itself off over the years of buying more batteries and customising boxes exactly for each dimension.

If the bits dont fit or the gun dies then Ill have to buy the gun that goes with these bits.

I'm still waiting for the clamps I need to bend the aluminium for under the down tube too....

 

[John Bozi]

I'm sure I could get these cheaper if I bought large quantities but for now not knowing which plastic to work with just got

25 rods of pvc
25 rods of abs

for $28 delivered of ebay... locally.

so far that's
$35 for a gun
$23 for the nozzles
$28 for these rods. Haven't sourced sheets yet... but it's adding up... to

$86
.......

My custom boxes will not be cheap! With sheeting anywhere between $250-$50 depending on new cuts or off cuts and sizes...Aluminiun fabrication is looking just as viable...

pvc is better for things in the sun
abs is stronger and easier to work with

Ultimately it will depend on sourcing materials. I cant find pvc sheets anywhere but they come cheap in drain pipes. abs comes cheap in cheap abs boxes and I can find sheets of it. hopefully sun damage wont be a huge issue. could always paint it I guess....

 

[John Bozi]

Must be honest I always charge my batteries in parallel - it's just such a pain to undo even more connections to do the individual cell balancing.

However, I've known for a long time one pack is the weakest and wanted to get more info on which pack was pulling the other one down.
Internal resistance

from drivers view

Right at front

10 3 6 5 5 5

3.5 3.7 3.6 3.6 3.6 3.6

left

5 4 5 4 4 5
all 3.6

These two packs are probably the oldest and most damaged. I ran them 12s 1p for a while at the start and also shorted them together.

So I don't know at what point to replace. I don't really want to use this brand again, but the rest of the batteries still have so much life in them. To just buy one 6s pack would mean yet another pack to be out of sync with the replacement life of the others. How do you decide?

Also

Over current protection

recently my power supply keeps giving me this OCP warning and stopping the charge.
I know I have been running two chargers off it at 9.6 amps for a long time and hadn't changed anything else such as voltage.

But have had to recently drop down to 9 amps and now this morning down 8.5amps because I was still getting OCP....

no idea why this is happening.

 

[drew12345]

John, never heard of plastic welding. I don't think I've seen anyone create a box this way. I look forward to seeing your custom box. Sounds like a neat project.

 

[John Bozi]

Yeah Drew I am excited to see what I can do or not...

I doubted I could fit 24 cells in the triangle, but felt I had to give it my best shot at least once as a plain box stack of four batteries.

4x6s wrapped with tape they fit.
With neoprene top and bottom they just fit.

With pvc custom folded case the box leans on the suspension..... every few mm add up .... :x

Quite a frustrating 4 hours of work and waste of tape.

I was really hoping they would fit this way so that I could easily remove the box and run 12s2p on my old tank to commute to work with.

I put the 18 cells back in the triangle and temporarily put the 24 cell box under the seat tube but it's way to wide and tall there. (ridable just) but no way a stayer.

Back to the drawing board.

 

[drew12345]

I like looking in the Before and After pictures thread. A lot of very creative ideas. Maybe the box can wrap around top tube to bottom and put your batteries above top tube and in triangle but conceal in the box.

 

[John Bozi]

I don't know what to think of the fact that many people know about my bike that I have never met.

From my youtube videos I have kids call out my name as I ride past the dirt jumps and skate board bowl.

And just from riding my bike around the neighborhood people often try to stop me for a chat. On the odd occasion I am going slow enough they run out to talk like the guy today.

I enjoy talking about it, but it's kind of a bit freaky if it increased my chances of getting in trouble.

Had a long chat with bloke today in this way.

PVC

I got my welding rods and just cant work out why melting the pvc wont make it stick together.

edit 1/11

got my welding nozzles and the main part doesnt fit the gun.............

Also have returned all the batteries to my normal set up of 12 under seat 18 in triangle and 12 at steerer


edit again

my dad helped me create rivets to make the new nozzles fit my heat gun but its overheating and nothing is happening.

I HAVE TO BUY THE RIGHT GUN

 

[John Bozi]

The cheap heat gun was not suitable to my plastic welding aspirations so have just paid $83 on ebay for

HOpefully this will work....

http://www.ebay.com.au/itm/161110477349

I am still researching and experimenting.

solvents

apart from thermo welding plastics can be dissolved together. seems easier. Just add solvent to both surfaces and the solvent liquefies the plastic together. sure will be stinky stuff.

here's a list I copied from http://nerfhaven.com/forums/index.php?showtopic=18527

Polyvinyl chloride (PVC)*
- 1,2 Dichloroethane: Y
- Acetone: Y
- Cyclohexanone: Y
- Dichloromethane: Y
- MEK: Y
- Methyl benzene: Y
- Tetrahydrofuran: Y
*Includes PVC in pipe and flexible tube, as well as CPVC as we use it, since our CPVC is simply Copper-sized PVC and not Chlorinated PVC.

Polymethyl methacrylate (Acrylic)
- 1,2 Dichloroethane: Y
- Acetone: Y
- Cyclohexanone: Y
- Dichloromethane: Y
- MEK: Y
- Methyl benzene: Y
- Tetrahydrofuran: Y

Acrylonitrile butadiene styrene (ABS)
- 1,2 Dichloroethane: Y
- Acetone: Y
- Cyclohexanone: Y
- Dichloromethane: N
- MEK: Y
- Methyl benzene: N
- Tetrahydrofuran: N

I've included acrylic here as I was looking into clear "plexiglass" ideas, could be usefull to have say a box area with clear top to see cell meters or cav3 inside...

Acetone should be easy to get to trial (just look through the mrs's draws) I also have some seriously strong paint strippers to dig up out of the shed to trial.

I will need to have the fan running because all of this stuff is seriously stinking toxic...

testing

I got paint stripper which MEK and toulene (methyl benzene)

and as it says above no for abs, but it also is not doing anything with the pvc. I don't know if there is something else why the pvc is not bonding.

Will try cleaning the pvc first with the stripper and then leaving it to dissolve.

acetone

its dificult to work with something that just evaporates so quickly. I managed though to get a puddle of it long enough to put two flat pieces of pvc that I had finely sanded and rubbed clean. I left them in the sun a long time to increase the solvents job and yeah it formed a very hard bond. It took a lot of twisting force to rip them apart again and the area where they had joined had raised higher, so some sort of chemical reaction is obvious.

I see having more than one technique will be very beneficial. especially if working with thin sheets which can be layered together. You cant weld between two overlapping pieces but you can cover the inbetween surface with solvent.

 

[drew12345]

Looks like a serious tool. Let us know how it goes.

 

[John Bozi]

LOl just got the hot air welder and first impression big and heavy and not comfortable to hold. Instructions refered to it as a blow torch at first.
had a screw loose

the air fan blows much harder, so hard I can clean my garage floor with it.

The air is separate to the heat which is an important feature my cheap gun didn't have. That means you turn it on at minimum 1 setting, then dial it up to setting 8 which in the instructions says is about 350 degrees C (my research showed is for pvc and abs, then after you finish the job, dial back to 1 and leave for "several minutes" to fan cool the element.

It still warmed up the part that you hold and I wear oven gloves.

The high air pressure makes it much harder to do jobs since one hand is on the gun and the other holding the welding rod. So clamps would be great to stop things blowing away, but this is accumulating $$$$

unfortunately another set back is that the high speed nozzle which I bought early doesn't fit the nozzle on this gun. and the other nozzle has already been made unusable for anything other than the old gun....

Anyway slow hand welding is still possible. I have a finer jet of hot air now and more control of heat.

I don't have abs sheet to work with (I cant find proof of the what my last tool box was made of and suspect its not abs because I cant weld the abs rods to it)

I have managed to weld abs rod to abs rod - but it ends up looking like someone spat on the floor.

I have managed to weld pvc rod to pvc drain pipe sheet but it warps the sheet quite a bit still. I think after sticking together I need to use a roller to flaten the job or compress it between some steel flat or something.

solvent glue welding

Tamiya for abs = It contains both Acetone and Butyl Acetate. Butyl acetate is used in nail polish but don't see a way to get it only without the other additives for nails.

is the only specific I can find cheaply to try. Well if you call $10 for 40mls cheap than yea. http://www.ebay.com.au/itm/TAMIYA-87137-Cement-Glue-40ml-for-ABS-Plastic-Model-Tool-/201190375621?pt=AU_Toys_Hobbies_Model_Kits&hash=item2ed7e180c5


Have been reading interesting stuff on forums for 3d printing usually about various solvents reactions to plastics and making your own glue.
http://www.soliforum.com/topic/2646/test-on-different-type-of-glue-acetonemeksub-lacquer-for-abs/

It would seem the cheapest would be to dissolve some abs into acetone to increase the bond... as I have both acetone and lots of bits of abs rod left laying around now.

 

[John Bozi]

Have taken a rest on the plastic work because I have more structural elements to get done first.

I gave the AFT consideration a long time because of the price. One day I may buy one especially when my current bike gets old and I can justify a new dh frame and motor to go with it.

But for now I am going down rare quite uncharted territory.

I am going to add the bafang 750w mid drive to my bike. $2k cheaper than aft

I choose it because it's small, clean and not too powerful (I hope) to drive through the hub cover/thread cassette.

Various issues have come up.
I can use my raceface with an adapter
Hopefully unicycle short cranks will fit the motor drive shaft. although Im concerned about the q factor. pedalling will pretty much become absolutely pointless.....

the next big decision is the rear cassette, I am thinking that putting this much power into the thread on cassette will basically mean it will be impossible to remove for repairs and bearing changes etc.

I am also considering going a single speed so am now investigating thread on freewheels....

Why do all this?

I love my hub - apart from (the weight which I cant solve) it is so inefficient at 0-20 kmh, heating up like mad, and eating 5000 watts to go up rough steep stuff.

I want the mid drive to take the brunt of this, but I dont believe a mid drive alone is my answer as it will also heat up like crazy, so having two motors to do what they are best at will be insane

if I dont destroy the side cover.... but they can be bought... etc.

On the motor pictured right you can see the threaded part, which I need to come up with a good solution. I am considering putting a huge sprocket or even chainring on if possible to gear this down even more.

 

[drew12345]

Hey John. So your saying have the hub and mid drive at the same time? I think someone has done this with some success. Sounds complicated with two throttles. Why not try a dual hub? 2 controllers with one throttle?

 

[John Bozi]

Yep drew,

mid and rear hub at the same time, yes there are a few people who have done it but it is still very rare.

It's dam hard to do searches on because you always get results "hub vs mid drive" instead of hub & mid drive.

I don't think it will be complex to have two throttles.

Especially if one is twist for the hub and thumb for the mid.

 

[pendragon8000]

Yep drew,

mid and rear hub at the same time, yes there are a few people who have done it but it is still very rare.

It's dam hard to do searches on because you always get results "hub vs mid drive" instead of hub & mid drive.

I don't think it will be complex to have two throttles.

Especially if one is twist for the hub and thumb for the mid.

so rare!
Have you tryed it yet? I found some motor rewinders I'm the yellow pages recently I wonder what it would be like to run high voltage high turn small wheel. Like 21s and 12 turn or something