Perfect choice then for jumps 
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Today I had the second ride in skate and dirt park, this time the trucks felt much more stable (with the compressed shock blocks) than yesterday or I got used to it. In skate park I was jumping almost 1m high off ramps with landing on concrete. Damn my ankles hurted 
. Also the deck is so stiff that I canât ollie properly, it feels weird and is effortful so I need to find a different technique.
After reaching dirt park I had some fun but like yesterday I couldnât jump as high as I would like because itâs impossible to ride faster than 30km/h (18.6m). I need a bigger dirt park 
For the first tim Iâve used RT data logging in the Vesc-Tool app and then opened the csv file on the computer in Vesc-Tool. The GPS is not working properly (maybe my fault) but itâs quite interesting.
These are the stats from the whole session the blue lines are the battery current in this case
The first part was skate park and riding to dirt park then a break to fasten all bolts. After riding shortly I had a problem with the enclosure and fixed it. The third part is riding/jumping at dirt park for 14 minutes.
So letâs take a look at these 14 minutes, now motor amps are the blue lines and battery amps the pink.
Average speed 15km/h and efficiency 25.52wh/km
Here the speed, max 22.54km/h in reverse 
Outside temp was 8°C and the Mosfets almost reached 60°C 
, itâs a winter jumper
Itâs interesting when zooming in (motor and batt amps)
Haha I realized every âhillâ is the acceleration before jumping and the break the jump itself. So the real hill is in between.
Looking at voltage sag, before acceleration the battery has 45.2V
With about 90A motor and almost 50A battery amps the voltage decreases to 43.4V so the voltage sag was 1.8V, not bad.
I was always wondering how much the total voltage increases during regenerative braking, now I got some data. Here while coasting the voltage is 48.2V
During braking here with max. -17A the voltage increases to 48.8V. Thatâs 0.6V or 0.05V per cell. So when braking with full battery the BMS will shut off immediately if the overcharge setting is 4.25V per cell.
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I didnât mention the settings so the charts (total values) above make more sense if you know them.
Motor 45A/-40A and Battery 45A/-15A each Fsesc.
Today I had the third and probably last ride of this week in dirt park and it was great. I could jump higher and clear the big table for the first time. I learned that I just need the balls to accelerate more aggressive in the short time in between the jumps
The board feels better and better, also the E-Toxx mini drive is awesome 
!
Itâs sealed, compact, the ground clearance is great and I really enjoy the powerful ride, itâs not comparable to belt drive at all. You can accelerate and brake really aggressive also on steep hills which is exactly what I need. Full power from the motors, so the new bottleneck is traction of the wheels . Also no more worries in case of impacts, perfect for heavy abuse.
Hail @NoWind and @Duffman for doing all the great stuff, hopefully youâll never stop 
In dirt park someone built this insane kicker which is (I guess fortunately) way to narrow for MTB.
It starts with a drop from the wood platform
Ready for take-off
Look at this huuuuuge suicide gap, on the left side is the landing zone 
Looks like a joke to me, just impossible. But what I realized is that bikes can jump higher and achieve more distance than me with about the same speed, no idea why 
.
The sound of the board when landing is completely different to the Trampa, it sounds like landing a snowboard on hard snow or ice, weird. You can hear the lack of flex. Also I stopped trying to push the board down before take-off because it just doesnât make sense. Instead I try to bend my knees and lift the board without assistance on take-off.Thatâs not the same but better than nothing.
I really miss the flex but on the other side the stiff board feels more precise and more predictable on heavy terrain because it doesnât bend/twist, therefore more direct feel and control.
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@rich
Thanks my friend, hope you never stop riding that hard, will help us to improove our stuff more and more !
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This build only makes me worry about truck strength. How much can those take before you get a lovely snapping sound followed by dirt everywhere?
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I guess I have to find out and hopefully itâs the rear truck
But joking aside Iâm not really concerned about a snapping truck because what I do is kindergarten compared to ârealâ riders/jumpers which are doing crazy shit with the same trucks. Iâve only heard once about a snapped truck and it was Dylan Warren himself. Also I saw a video where the F5 binding snapped after a crazy backflip fail in skate park. When you crash hard enough you can destroy everything no matter how strong it is.
Iâm more concerned about the axles which could eventually bend. If I order some special bearings I could reduce the track width for about 16mm and preserve them a bit.
From my 3 rides so far 2 ended with an empy battery and walking home. The 12s 5Ah lipo (222Wh) is nothing and I get a poor range of max 8km (5miles). I have to think about a solution for swappable packs, maybe 12s3p or 6s3p packs made of VTC6. Good thing is that with just a tad more weight I could increase the range to about 15km (9.3miles) with 389Wh. Bad thing is that they cost money . I guess I have to build one pack first and see if voltage sag is a problem in real life. In theory the 12s3p pack has about 4.8V voltage sag when drawing 50A from battery which is not glorious.
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The axles would definitely be a weak point. Iâm surprised no one manufactures trucks where one has the extended axle and the other has just a huge hangar. That seems like it would be way stronger although much heavier.
Also yeah you definitely need a bigger battery on that sucker. Who am I to say tho, rocking my 4s 16Ah lipo ;D
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Where is the reference for the VSag? I looked around and wasnât able to find this. Iâve been considering building a pack with VTC6s but am not 100% sure if thats the approach I should take over building another LiPo pack.
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I donât know if it is scientific correct but I take a look at discharge curves. Here a comparison of VTC6 and 30Q when drawing 15A/20A each cell. At the beginning of the curve you can see how much the cell voltage drops from 4.2V.
In my example of 50A total (3p=16.7A/cell) it drops to about 3.8V. So 0.4Vx12cells=4.8V voltage sag (with full battery).
Itâs easier to count with letâs say 60A total, here a 3p so 20A each cell. In is chart you can see the temperature rise and the real usable capacity.
A 30Q is good but according to the charts the VTC6 is better
Also I thought about a 2p with 40T which would be 30A each cell.
Itâs not optimal but I need a light battery.
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I had my 4th ride on friday in the early evening. It was raining during week so dirt park was no option thatâs why I rode to skate park to empty the battery. Damn I had no idea how straining it would be. I have sore muscles, my legs, belly and even the ass hurts. Yesterday it was even a challenge to walk or sit down at work, today itâs a bit better. It was a little dark already but I recorded some footage which needs more editing but should be finished soon.
For now some stills.
Well the board has some marks from skate park. I didnât mount the driveguards yet because I wanted to check for eventually lose bolts after the first rides (which didnât happen). I landed with one motor plate with full weight on a concrete/steel edge. Steel is stronger than aluminium . No problem but from now on I ride with driveguards.
Deck after skate park
I have some scratches on the rear hanger but fortunately not on the motors (yet).
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Did you think about some etoxx motor protections for Matrix2 trucks? I think they wouldnât add much weight, but could save your motors one day in the skatepark
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I think they donât fit because with the 8T helicals (instead of 10T) the motors are closer to the hanger. Also Iâm not sure if it exists for the mini drive, on the homepage I see them for maxi drive only. But anyway I need to save weight so I hail skatan for unharmed motors.
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Oh i didnât know they work only with the Maxi drive or higher pinion teeth count, so yeah, than just lets hope the best in future 
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Damn love this build.
Those wheels look great on there.
Canât wait to put my DW together.
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Thanks bro 
I have one more damage from skate park which I didnât recognize at first. The left palm protector broke and fell off, damn.
I love this gloves, they saved me from a lot of pain . I ordered some new full- and half finger HillBilly wristguard gloves today from MBS EU. I recognized many things are already out of stock due to black friday 20% sale, who bought MY set of T1 tires and bushings?
The front hanger got quite loose, very strange because there is a lock nut on the kingpin but after tightening it looks solid again. I mean I hope it was the lock nut.
Right now Iâm exporting and soon upload the video of skate parkâŚ
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Thanks for reminding me 
Just picked up the impact shorts, set of tires and wheels. need to find a nice full face helmet before December 31st though. Still have 3-4 hundo left in my âstay fitâ budget from work 
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Ruroc!!
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