KMX Typhoon midmount Minimonster 2 speed hub motor

[John in CR]

Looking good. Are you still running 24s? Top speed? I'm trying to get an idea of your gearing compared to how I've run mine with 20s. I don't have any extra sine wave controllers, so if you blow that one using 24s, a sine wave replacement won't be a similar bargain, not with 4110's. On the flip side, if it's geared as low as I think then you should be able to boost the current some if you need harder launches.

 

[Trilska]

So far i have only used an old 5A 18s turnigy pack, but the final pack is 20s. As far as topspeed goes i have no mesurement of that yet.
The drivetrain sure works fine exept hitting lvc due to the old tiny pack, but i would be very suprised if i manage to bust the controler after last nights uhmm... activities But once everything is finished (probebly only halfway there) i might start tweaking the controler

 

[Trilska]

Tiny update

Calibrated the speedometer and tempsense (winding temperature).
Might not be the most impressive thou, just toped out at 53 km/h with fresh batteries.
On the temperature front i have not exactly reached the limit... only got it to around 40C, even thou i tried to with reapeated quick start stops... Getting the feeling i would overheat the brakes before motor at this point.

 

[John in CR]

It sounds like you hit your gearing target on the head, a nice low gearing for efficiency and low stress in the mountains. It sounds like you're into the fun part, so as long as you're happy that's all I care about. Other than to spin motors up and check the sound, I haven't tested those little 12fet sine wave controllers, so I look forward to your reports.

 

[Trilska]

Bha! the hygia brakesystem konked out for me... well back to stock mechanical while searching for an replacement.

Ps. Tried to put individual hydralic brakes for each front wheel just to try and see how it feels. It did not exactly inspire coinfidence. Ds.

 

[Wheazel]

What actually happened with the hygia?

 

[Trilska]

Shortend the hoses (way to long and messy to start with and not aceptable with the buildquality i am aming for), could not locate the corect olive and conecter insert, so i had to use a similar kind. After the hosechange i bleed it properly, repositioned cylinders i had no air in the system, no leaks and i could not gain any preasure on to the disk. The cylinders were moving properly but no actual force behind them. Have probebly spend around 5 hours today and 3 yesterday trying to locate the error.

 

[xenodius]

I'm using dual BB7's on my kmx and wouldn't switch if you paid me. I have hydros on my 29er but I rode my kmx in freezing weather that ruins the seals... mechanical is easily serviceable and very reliable I like having individual control, around corners you need more outer-wheel braking to prevent traction loss, since more weight is on the outer wheel. Maybe I have great toe, but I feel like my kmx tracks straighter than my bike and is more stable at speed, too.

Looks like a great build!

 

[Trilska]

Manage to squeese in a few hours on the projekt even thou exams are closing in.
Have configured batteryelectronics and build a temporary housing/mountingplace, and will hopefully be able to take it for a testride soon.

The components in this mess is the batterys (20s 2x8Ah) the foundingpower BMS and a kilovac EV200 relay along with other accesories.


The relay is bypassed via a toggleswitch with an inline resistor, to power up the 12V side and feed the relay holding curcuit, and thus making the toggleswitch abundent and the holdingcurcuit is active. The relay is closed via a braker in series with the relay holding curcuit.


BMS display, all cells betwene 3.78 and 3.79 V. The 100% battery status needs to be calibrated.

Cant wait for my exams to finnish to free up some time to work on this baby a little more intesive.

 

[Trilska]

A little update now when i have put some km on the bike (exams are over so now i have plenty of time).

Speed wise i have had it up to 63 km/h with a fresh charge and had an energyconsumtion on around 17-29 wh/km.
And top power around 2.6kW (not peak).
And a peak copper temperature of 49C

But i am having some issues with the controller. First and foremost i only manage to draw a steady 35A during acceleration (rated at 50A) so it seem to be slightly down on power.

Being a little down on power is no real issue compared to what follows now.
After around 8-9 km it seems to go in to some kind of protective mode, and simply refuses to provide power. Reduce throttle signal and then back up again and it give a slight blip of thrust and then it is in to protection again. This happens after non-agressive riding (flat ground and 25-40km/h)=. What is even more odd that even if you turn the system of let it sit still 15 min the issue is still the same.

It does not seem to be entirely heat related (10 min of intensive wot and braking works fine) and on flat ground at relatively steady speed and no braking it enter the protective mode. Any ideas of what the reason for this could be sure would be helpfull.