Mark_A_W's DH Team/MAC Shanghai/64v Headway build

[cell_man]

Best of luck with the build Mark, 60V on the Mac motor should be nice.

 

[johnrobholmes]

Keep the banter out of this awesome build thread, I pruned a few posts of dribble.


Awesome build here. I ran my MAC on 18s lipo and it broke the gears when I hit a bump at speed. A metal gear should solve that. I was running 45a current limit and I never overheated the motor, but I am about 150lb rider. Gotta say it was one helluva fast hub motor!


What do you think your final weight will be?

 

[Mark_A_W]

More pics added to third and forth post.


Thanks for cleaning the thread up John, although some of those performance specs were interesting.

 

[Hyena]

Looking good Mark - time for a test ride and video eh ?

I ran my MAC on 18s lipo and it broke the gears when I hit a bump at speed. A metal gear should solve that. I was running 45a

That's impressive John, it must have gone like a shower of shit running upwards of 3000w into it!
How long did it actually last before you killed the gears ?
I'm thinking of trying one on 18S but I thought I'd probably have to limit the current around 25-30a. If yours took 45 without the motor itself getting too hot that's a good sign though. With metal gears and 30a on 18S lipo it should be a great little performer.

 

[Mark_A_W]

Sounds like it was the bump more than the power, which is concerning, as I fear the metal gear is going to be far too noisy.

I'm thinking about taking the gear to a gear manufacturer, and seeing if there is something inbetween nylon and steel. Perhaps cloth-reinforced bakelite, or a glass reinforced plastic.

 

[voicecoils]

I'm thinking about taking the gear to a gear manufacturer, and seeing if there is something inbetween nylon and steel. Perhaps cloth-reinforced bakelite, or a glass reinforced plastic.

Glass reinforced plastic is what the BMC V2 are supposed to have FYI

 

[Mark_A_W]

Yeah, it's a pretty common solution. There's a whole world of plastics and additives to choose from....if you have a mould, or a hobbing machine.


I actually wonder if the BMC gears will fit? I can measure my spare MAC gear, but the only BMC is I know of is yours

 

[Hyena]

What's the latest Mark ? Any on road testing / impressions ?

 

[adrian_sm]

I took it for a spin yeserday, and it is nice. Very nice.

It feels really solid, well balanced, brakes are great, torque and speed were really good.
Looks a bit more like a motorbike, with big fat Hookworms, and triple clamp front end.

There was some weird issue with vibration from the motor below say 10-15km/hr. Probably just requires a bit of tweaking in the controller firmware. Once that is fixed, and the battery enclosure is in place, it will be one very sweet ride.

Nice job Mark.

 

[johnrobholmes]

The vibration is normal at the lower speed, right until you hit about 25kmph. An interaction between switching frequency and chopping frequency best I can tell.

 

[Mark_A_W]

Get back to work Adrian....ooops me too.


Yep, initial review and pics coming, hopefully today at lunchtime.


Short version: Fark it's fast (55kmh). Handles brilliantly. Loves eating bumps.

Issues: Oscillation/shudder at 10-15kmh, quite severe. Controller seems to have a stall detection feature which is too touchy, and not consistent. Could use a bit more down low torque. I can do wheelies but they are a struggle. Metal gear screams, want to try BMC Composite gears.

I actually want more current down low, and less current up high. But I am using a high KV motor with a high voltage, so that's what I got.



And yes, it's a duct tape special at the moment, the battery box isn't ready yet.

 

[Mark_A_W]

Keep the banter out of this awesome build thread, I pruned a few posts of dribble.


Awesome build here. I ran my MAC on 18s lipo and it broke the gears when I hit a bump at speed. A metal gear should solve that. I was running 45a current limit and I never overheated the motor, but I am about 150lb rider. Gotta say it was one helluva fast hub motor!


What do you think your final weight will be?

Bike weighs 36kg (79lbs) and I weigh 88kg (194lbs).

 

[Mark_A_W]

The vibration is normal at the lower speed, right until you hit about 25kmph. An interaction between switching frequency and chopping frequency best I can tell.

When you say "normal", are you talking about a minor noise (like my Direct Drive motor did at about 25kmh), or something more severe?


If I just go WOT from standstill, it's smooth to about 8-10kmh, then starts shuddering quite violently, and really gets bogged down till about 15-18kmh. Then it screams off to 55kmh.

It feels like the whole rotor assy is bouncing off the sprag clutch on the planet gear carrier/axle. I'll try and get a video.


However, with careful throttle management, and addition of APU's (legs) it can be managed. It's almost second nature now to avoid it, I have to ramp the throttle through the rough zone, then I think the planet gear carrier stays firm against the clutch, rather than bouncing off it.

But it would make it difficult to ride offroad.

It doesn't do this with no load/light load. No load is smooth.

 

[johnrobholmes]

I haven't experienced shudder with my setup, it was more of a growl.

 

[Mark_A_W]

I haven't experienced shudder with my setup, it was more of a growl.

What volts/current limit/controller and is it a MAC Shanghai or BMC motor John?


My motor looks like the Puma on your website, except it's painted "metal grey", rather than raw ally.


At 48v it would do about 55kmh no load, I'm running 60v nominal, which is 80kmh at 66v no load.

And I have the 18 FET Infineon with the current limit set at 30 amps.

 

[johnrobholmes]

Looks like mine is a MAC as well, but I am waiting for some motors from them direct to know for sure. Running 12 fet infineon on 18s lipo 45a limit. Did you adjust your limits on the controller?

 

[Mark_A_W]

Looks like mine is a MAC as well, but I am waiting for some motors from them direct to know for sure. Running 12 fet infineon on 18s lipo 45a limit. Did you adjust your limits on the controller?

Yes, we reprogrammed the controller and I reduced the battery current to 30A and the phase current to 75A (from memory).

I might play with raising the phase current.

Unfortunately, there was no way of reading what the settings were before we programmed it.


And your voltages are basically identical to mine, which is very helpful.


Thanks

Mark

 

[Mark_A_W]

Changes from photos:

- Rear light moved to below seat.

- Plastic "oggy knobs" added to steel torque plates at motor. To protect the wiring and derailleur when I fall off.

Things to do:

- Sort rear mudguard

- Finish battery box

- Play with controller battery current and phase current limits to see if I can reduce the shudder.

 

[AussieJester]

Good too hear its running Mark how far off is the custom battery enclosure? Hope you can
sort the 'shudder' issues out to, is it really a big problem though for on road riding? I gather
though with the suspension on this bike your planning on some off road excursions too?

KiM

 

[Mark_A_W]

Good too hear its running Mark how far off is the custom battery enclosure? Hope you can
sort the 'shudder' issues out to, is it really a big problem though for on road riding? I gather
though with the suspension on this bike your planning on some off road excursions too?

KiM

The shudder is manageable, I've already subconciously learned how to manipulate the throttle to almost eliminate it. It's really when someone else rides it. So, not a huge issue for road riding, but I would like to fix it, or reduce it to a noise, rather than a shudder.

Battery box is a week or so away. One side is sanded nicely, the other side needs another sand and maybe bog. Then painting.
(Black? Blue? Paint needs to be robust, but not rough or it will grind my leg. Ideas welcome).

No real plans to take it offroad. Except that a large portion of my commute is on dirt with ruts and potholes. Everytime I go offroad riding I come hole bleeding.

 

[Hyena]

Is the shudder problem the same one that were reported with BMC's on infineon controllers (I remember reading somewhere people were getting better results on the analog controllers than the digital ones) ?

55 km/hr isn't too shabby - so that's on about 63-64 real world volts ? 18S lipo will sit above 70v for alot of its discharge so you'd probably expect around 60km/hr. Have you noticed what sort of current its drawing WOT along the flat ?

I'm going to try one of these MACs too, I'm hoping to get similar performance to my modded GM hub but while drawing less current.

 

[Mark_A_W]

Is the shudder problem the same one that were reported with BMC's on infineon controllers (I remember reading somewhere people were getting better results on the analog controllers than the digital ones) ?

55 km/hr isn't too shabby - so that's on about 63-64 real world volts ? 18S lipo will sit above 70v for alot of its discharge so you'd probably expect around 60km/hr. Have you noticed what sort of current its drawing WOT along the flat ?

I'm going to try one of these MACs too, I'm hoping to get similar performance to my modded GM hub but while drawing less current.

Gotta link to any info on the BMC issue? Same motor, same controller.

I'll be interested to see how full-throttle goes, it'll be a week or to. He has the MAC motor and a 12FET infineon.


I don't wanna go faster than 55. I find myself crusing at 45. Everybody looks when you scream past at 55...except for cars, they don't see you at all. So no, no more volts needed.

It's drawing 1500+w at 55kmh, so about 25amps.

 

[AussieJester]

(Black? Blue? Paint needs to be robust, but not rough or it will grind my leg. Ideas welcome).

I would of suggested colouring the resinb but sounds like the box is now built and being finished for painting?
If this is the case i would go with a 2Pac paint its what i plan to use on mine, sprayed a bit of it over the years
it dries with a nice hard finish, You put down the colour then clear over the top, some call it clear over base.
Its pretty pricey good for you though you will need only small amount, comes in two tines the colour and hardener...

I get what you mean by its manageable to but not good for others who ride it, my cruiser was the same with the rear 3 speed issue, fine when i rode it i could manipulate the throttle lightly enough to avoid it thrashing the hub to bits, soon as a mate jumped on it though they would can it off the mark and all that happened was the hub slipped and made horrible noises haha...I like things to be 'bullet proof' though so anyone can have a good ride, im sure you will sort it with the help from the brains trust here...

KiM

 

[Hyena]

Gotta link to any info on the BMC issue? Same motor, same controller.

I can't remember if the shuddering was the issue or something else, I just remember there being certain issues with the BMCs and different controllers.

There's this thread which you posted in yourself, talking about the high number of poles and need for a high electrical rpm controller
http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=16473&p=242573&hilit

and this big BMC one. I don't have time to wade through it but there's more talk of different controllers in there.
http://www.endless-sphere.com/forums/viewtopic.php?f=3&t=11205&p=196463&hilit

 

[Mark_A_W]

Better correct my post in that BMC thread.....my Infineon works well with the MAC on the BENCH.


Had a ride around the backyard.


Noticed two things:

1. It seems very mechanical, the motor is bouncing forwards and backwards, and doesn't accelerate. If I ramp the throttle gently, keeping the pressure even, then it doesn't happen. But it's not a matter of just using less throttle, it will still do it at low throttle. The speeds that shudder occurs at can vary from below 10 to 20kmh.

2. Just as I thought it was mechanical, I noticed the current. When it's shuddering the current is below 7amps, no matter the position of the throttle (even WOT). The CA should be jammed on the 30amp limit at these speeds. Once the motor clears through the shudder phase the motor screams off at 20+ amps.



My working guess is my phase current limit is screwed and sending the motor square waves or something nasty. Anybody else have any ideas?

I will collate all this info and create a thread in the Technical section.