Destroyer 12s Urban Racer Build

1 horsepower motor.. low emissions... should upgrade to a wireless controller though...

I dare you not to laugh...

[youtube]4UfXx8PO_lw[/youtube]
 
Having burned up my airplane HV ESC while riding through an upturned sprinkler on the destroyer...http://www.hobbyking.com/hobbyking/store/__38787__The_Turnigy_Sentilon_V4_HV_100A_OPTO_5_12s_Bulletproof_Speed_Controller_w_RPM_Sensor.html I decided to try a Boat esc..http://www.hobbyking.com/hobbyking/store/__8945__Turnigy_Marine_80A_HV_Brushless_Boat_ESC.html I chose a boat ESC as it clearly states that it has 3 settable braking alternatives (not dynamic braking but true braking)
ScreenHunter_01 Jun. 21 11.17.jpg The ESC is 80 amps constant but from previous wattmeter tests i know i go nowhere near that..

Waited about 5 weeks for the stuff to get here as I had to buy from the international warehouse.
The Esc got here uploaded the manual.. and guess what..... there is no braking on the ESC. Could definitly be worse as the destroyer has the alternate band brake, but still kind of crappy considering that had been the sole reason for the boat Vs airplane selection.. commented to customer support that they should change the description.. they then proceeded inmediately and in a totally efficient manner to ignore me ... :(

Since this was going to be a 12 s board I ...Lowered my motor sprocket to 11 from the previous 14 tooth.. in an effort to lower my max speed to a (barely) survivable 60 kph from the deadly 80 kph potential... I already requested a 9 tooth to further limit my max speed to a more managable 50 kph and it should be here within the next 15 days or so... I have also ordered a pound of maturity and a gallon of wisdom... see if I can simply be an adult and not gun it to the max... :shock:

Hooked 3x5000 mah 4s in series for 12s.. connected my wattmeter and went for a nice stroll today, no maxing out, no crazy anything just a test to see how the board/motor/bateries/esc got along. Got a nice 18 km range.. Max speed was around 44 kph with a wopping 44 peak amps... nowhere near full gunning no crazy anythings. The motor felt slightly sluggish at times so I upped the timing a bit. The quanum (can't use the wiimote on this as it lacks the second control for my servo bandbrakes) felt squishy.. so i reset and centered it and got a much nicer crisper response.

So quite happy with it overall..If i had to do it all over again I-d probably get the sentillion just cause it looked nicer and it had the super soft start option which was just creamy smooth...
However the boat option will hopefully withstand panama weather better I guess. :D
 
Googling plastidip as we speak...
 
You can also use silicon sealant to pot electricals, best use neutral cure for electronics to avoid corrosion of components. Tegaderm will allow the silicon to cure and create a smooth surface finish. :idea:
 
Hmmm
Maybe not so happy with my hv boat esc...
Tried running it harder today and it overheated several times. .
Throttle cut down to 50% ruining the high...
Not complaining... this is a boat esc being used out of the water.. just sayjng.
So i ordered another sentilion..which should be here in a month's time..
Guess that is the end of my boat esc ventures. ..
 
Well after quite a bit the sentillion is ready to run.. will take it out tomorrow for its maiden voyage...
used the time to upgrade to 10 ah at 12s... which should give me awesome power/speed at a tiny max-amp rating of 45 or so... (probably closer to 30 average)
Also they will come in super handy as a new bike route opened up and the new battery should give me a range of 45 kms or so...
So tomorrow is basically an easy runthrough just to make sure nothing breaks down or falls apart.. and if everything goes well ill give it a second tougher trial run on thursday and then try and go the distance on sunday... It should be 43 kms roundtrip...

hell of a walk if something goes wrong... :shock:
 
Finally got the destroyer out for a lap on the newly opened eastern side of the city wide bike lane.

The reconnected at 20,000 ah at 6s just to make sure I didnt get carried away and die on the route LOL... didn't trust myself with the 12s connection and those long straightways...

Well it was awesome... for the first time ever.. and I mean ever.. i had battery power left when I was done wanting to ride LOL. The complete lap was 30 + kms.
View attachment 2
41 kph maxspeed..

Screenshot_2014-10-12-08-59-15.png
One and a half hour lap...

ScreenHunter_186 Oct. 12 09.50.jpg
Pulled max 66 amps at 6s.. and there were some nice ups and downs...

Nothing is free though...the Board is heavy as hell and I really dont look forward to ever having to hoof it for any lenght of time LOL...
 
So against all my common sense i ended up connecting the 2 6s in series for a nice 10ah 12 setup... the tacons should be able to andle comfortably anything up to 14s so that figured everything would be ok...

Today was Panama's international marathon (or is it half marathon?) so at 6:30 am a couple really nice streets where closed for the event..there were also several ambulances along the road.. and it was a gorgeous morning...As usual I was out in full motorcycle armour and my closed downhill helmet.

So I was able to go for the first time ever on this straightaway that is about 1.5- 2 kms long.. and the asphalt was incredibly smooth..the last marathon runner passed this point around 730.. i asked around and the roads would be closed till 10.. so i figured.. 12s ESC, 10ah batt, onda wheels, perfect asphalt, and ambulances within a couple hundred meters.. This was the time to bring the destroyer to top speed... not my top speed... the destroyers top speed... time to pull the trigger all the way...
so I tighthened the trucks as tight as they would go I did three test runs each one going a bit faster than the one before...making sure there were no cracks or equivalent death traps... finally went for it and it was awesome.. the Tacon made its ultra high pitched whine, the chains jingled, the onda wheels just rolling on the perfect asphalt... soft breeze flowing.. my heart doing about 300 bpm... it was awesome...

The single engine tacon flew up past 62 kph with a 200 lb guy on it... It pulled a hefty 72.2 amps while doing this at 46.25 volts for a cool 3339.25 watts... interestingly the tacon is rated up to 2700 watts.

ScreenHunter_198 Dec. 07 11.58.jpg

Unfortunately this is a deadly game.. a fall at this speed is just way to much to handle so I`m trading in my 245 kv tacon for a 192kv cause im in love with the low amp requirements of my 12s system but i cant be trusted to keep my speeds under 40kms which is probably as fast as i should be going..

Awesome experience.. but enough is enough..
 
Balls! I can't imagine those speeds. I'm riding max in the low 20s - guess I'm getting too old for this.
After reading your post I had to dig through to find out how the guy (Jaystcb) was doing that is going for the guinness record. Here's a quote from Silverfish:

Thank You for watching the video. We have gone through several boards. Currently, I am riding a Purple, Rogers Bros. DH-37. I blew up my electronics and crashed in epic style. I have spent the last month recovering. I am finally able to walk without a limp. My elbow is still tender to touch. I was using a castle XL2 speed controller. The internals melted and ceased the motor. I was in full tuck. I dont know my exact speed at the time of impact because I lost the speed info and the video on the GoPro during the crash. It took me 30 minutes just to find the GoPro. Lucky for me I was fully geared up with my leathers, exta pads, and helmet.

Some vid:
[youtube]Fm-0SgVSyD8[/youtube]

His new setup:
10724983_856842931001670_1665590890_n.jpg


Definite props to you. Maybe we need to start an eboard racing circuit!
 
80 something. ? Wow..
Needs bigger wheels..I wouldnt dream of anything approaching these speeds without my 7 inch onda wheels..
Also im 42 years old.. so doing the math 62 kph at 42..is like doing 82 at 20 LOL...

That video looked fast! :?

A double sentilion setup, on 12s batts, 7 inch onda wheels, 14:34 gearing, twin tacon 245 bigfoots...any under 180 lbs rider should be able to go over 100 kph on flats.. double that again with 14:17 gearings and 4 sentilions, 4 wheel drive, 4 tacons... and you should do over180-200 kph...In none of these cases is the problem power...the problem is staying on the board...
 
okp said:
inspiring ! this make me think of making a dual diagonal motor (2028 NEU) with two mamba xl2 as ESC on a 7S 10AH... should be plenty of power :)

Double motors will always allow you to go fast on flats.. 7s on twins will allow you to go over 60 kph easy...just make sure your gearings are correct, and you might have to sacrifice hill climbing here. For me it is not an issue as i live in a flat area...
 
Hi bto_pty, almost forgot to congratulate you for this speed record
I had a look to our "battery range" chart and you end up nicely on a cubic law for the aerodynamic drag where 1m2 of frontal effective area was assumed since the beginning:

means the power required at those speed follows a "P=$D$2*0.5*1.2*(A3*1000/3600)^3" formula where $D$2 is equal to S x Cx = 1m2 and A3 the speed in kph, would you please try the same ride shaved and naked to see how much potential we have in term of drag coefficent ? thxs in advance :lol:
anyway... take care :twisted:
 
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