"Velcro Board" | MBS Core 94 | Idea ATS mounts | Single SK3 149KV | 12s LiPo | ESCape

I finally decided on my components. Thanks @Der6FingerJo, @rich, @AndyBigD and everyone else for help! Starting my “Velcro Board” build page. First, why Velcro Board? I want to build an electric eMTB that can be easily converted to normal MTB, so that I can use the motor for getting to kiting spots, remove the motor/battery/ESC and use the MTB for kiting. More about that here. It will be something that’s easy to put together and take apart again, same as velcro. Plus, I think the build will rely on actual velcro heavily. :slight_smile: And I kinda like the name. So Velcro Board it is… or it will be… I hope.

To do the conversion, the plan is to have two hangers and two pairs of wheels – motorized and normal – and swap them.

I will keep this page updated as I progress in my build.

For now, here’s the list of components and expected budget:

Total: ~1000 EUR

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Looks nice! Be sure to use really broad pieces of velcro. I use 100mm Velcro strips for my Batteries and they work beautifully.

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Seems like a solid list! So are you going to fit the twin motor mounts but only fit one motor? See no reason why not! And are you planning on getting the 62T or 70T Wheel Pulley for that mount? Only reason I ask is that with 168kV, might be geared too high with the 62T, 70T seems about right…

Thanks! Yes, only a single motor on the twin motor mount for now. I might add second motor later though.

For MBS, @idea currently only makes 72T. That makes for 4.8:1 gear ratio with 15T motor pulley. It should be capable of doing ~50 km/h, which seems a bit scary. Wouldn’t 149kV actually be a better option?

since you already have a good source, where did you buy them? Toom Baumarkt is getting expensive :stuck_out_tongue:

@janpom good luck with the build. You’ll be addicted to e-power.

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Get a training kite, zoom past others riders leaving them completely confused

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Ahh, 72T is it. Could still potentially be a bit on the high gearing side, especially if there’s only one motor. Top speed around 45 - 50 km/h;

149kV might get you a bit more torque for running with only 1 motor, speed drops to around 40 - 45 km/h;

Range should be a respectable 20km with 8Ah

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Just bought them from amazon, just search for 100mm velcro.

I’m a fan of not speccing you board for speeds you wouldn’t want to reach anyways, so i think this is good. Makes it a bit more efficient too.

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k, I’ll go deeper into the subject. I’m afraid of buying a velcro type that is too strong and will simply rip the adhesive part off. This has happened with the stuff I got that was supposed to be ‘‘industry strength.’’ Since there a multitude of brands, it would be good to know what has specifically worked for you.

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I’d agree with this. Go 149kV for now, give you more efficiency and more power for the speeds you’ll want to start out at. If you to move to 2 motors, and are happy with the speed but want even more power you can get a 2nd 149kV. If after some riding you decide you do actually want more speed, then get a pair of 168kVs…

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40 km/h is more than enough for me. OK, going with the 149kV instead. Order submitted. Thanks!

(I wonder why HobbyKing says free shipping and then they charge me 11 EUR on shipping.)

Nice! Don’t forget to file a flat spot on the shaft for the grub screw of the pulley. I have 150kv and 1:5 gearing and that’s totally fine. Usually I ride between 25-40 km/h, sometimes above 40 km/h but then I’m scared to fall and don’t feel comfortable. IMO It’s better to have some torque instead of crazy top speed :sunglasses:

That happens to me on amazon :laughing:

If you use your 2 chargers at the same time don’t forget to unplug the serial connection of the 2x 6s Lipo packs (2x 2x3s packs) otherwise you will kill one charger, both chargers, or the lipos :wink:

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Had a mistake in my range calculator (I had input of Wh/miles but was putting in values for Wh/km). With that corrected you are probably looking at a range of around 15km with an 8Ah battery. Obviously the range calculator is heavily based on assumptions; Energy Usage is just an estimate, and Useable Pack Energy assumes you can only really get upto 75% of the Energy out of the pack. (i.e. you’d be putting around 6000 mAh back into your pack when charging, probably a fair estimate). image

If you genuinely need 17km, you might be able to achieve it with efficient riding, but you may need a higher Ah…

Hm, I didn’t realize I couldn’t use 100% of the energy in the battery pack. OK, it will probably be tight. We’ll see. I have already placed my order. I could maybe make an extension battery pack (with less mAh) to carry along in a backpack and swap the batteries.

I still hope the 20 Wh/km is for off-road while I’ll mostly be doing on-road with not many hills, so I’ll be able to do better than 20 Wh/km. Anyway, I will test it before worrying about getting more power.

There’s two spots I usually go to. One is about 7 km far and the other about 8 km. I may need to stop using the latter. :smile:

Don’t worry about range. With my 12s 8Ah lipo i have a range of about 20km. When I ride like here in the video it’s about 18km, my record with such a pack was 23km :grin:

EDIT: forgot to mention that I discharge from 4.2V to 3.5V per cell to get that range

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This looks so much fun! I can’t wait to get my build finished.

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You people and your flat country side :stuck_out_tongue: I discharge to 3.7. My drone lipos were all killed very quickly going lower than that under load (these are 60-120C).

Anyway, don’t matter. Range is very personal/setup/driver/area related. You’ll find out what works for you.

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When you discharge Lipos slower than in a FPV Copter it’s safe to go with a lower end voltage. A friend once killed my new 1300 5S Graphenes by discharging them to a half empty 3S battery during 150A punch outs :rofl:

I discharge my board lipos to 3,7V if i can, but if i need a bit of range at the end to go home i have no problem with 3.5V/cell.

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:laughing: Austria has hundreds of mountains above 3000m but the highest hill in my area (vienna) is 592m :wink: Need to travel more but I have no car, only 2 esk8’s.

True, I just wanted to point out that 16km is no problem on “flat countryside”

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Oh you’re from Vienna? I’m from Brno. We’re basically neighbors. :slight_smile:

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