Hi everyone, my name’s Stefan, I’m an architect and I’m from Bucharest
Together with my friend Adrian who’s a last year student at polytechnics university (electronics) we upgraded my original eskating.eu 10s3p single motor kit to a dual motor 10s5p 11.5kg board great for city riding and commuting.
I’ll also add a small history to explain some of the decisions and hopefully give you guys some insights into the process and the lessons learned
So I got the original kit from Alberto in july 2018 and until last year I probably put around 4k miles on it mostly using it as a commuter board in Bucharest (9km round trip to my office) and weekend joyrides
I got a cheap “mall brand” wooden board that lasted me for about 2 years but I felt it started to wear down especially on the front where it got a lot of impacts and started vibrating strangely which told me I needed to upgrade it.
So in 2020 I upgraded to Landyachtz Switchblade 40 which looks pretty cool and it did give me a lot more “feel” for the movements of the board and trucks
But it came with 2 downsides that I didn’t initially consider: weight, it probably added 2 kg extra and stifness - it became a less comfortable board to ride. Switchblades are very stiff boards apparently
A few months later, after multiple problems with the original 4.12 50A Maytech VESC which in the end had a DRV failure, I “upgraded” to SuperFOC 6.8 50A Maytech VESC which kind of solved the issues with the cutoffs (but not entirely)
I think the problem with the cutoffs was the fact that I kept a pretty aggressive setting in the VESC, going for 50 amps for the battery max which even though should be the max setting it seems that in reality maytechs and flipsky small VESCs like this need to be configured more conservative (40-45amps)
But the main issue was the riding experience, a very stiff board coupled with the MBS “All-Terrain” wheels, it became a not so fun board to ride. So I started to look for softer wheels and I upgraded to ONSRA’s 115 rubber wheels:
And they were perfect, a lot smoother ride, not so many vibrations… I thought finally the setup is finished. But… the downsides of these guys:
battery almost halved and sagged very bad starting at 35-40%
the bigger 45t pulley on the wheel vs the small 14t that was also very close meant I had a lot of belt slip
I kind of fixed this by modifying Alberto’s original mount and adding a tensioner:
But this lasted me around another half of year and the experience degraded so much that I kind of stopped using the board.
So last year (2022) around this time I decided that after 4 years of service the battery was probably also one of the issues and together with Adrian who had experience building batteries we planned a bigger upgrade. It was clear that the new wheels needed 2 motors and a bigger battery to push them even though it meant having a heavier board (the original one was approx 6-7kg). But I didn’t want a very thick, very heavy board.
I also wanted to keep motors mounted under the board (inbound?) because the shape of the board gives me the option to kick-rotate it on the spot which is a good thing to have in a big city with tight corners.
So the 2022 build started with an order for new wider trucks, new mounts, 33 new Samsung 30q cells (17 of the old ones Adrian tested and seemed fine) and new motors
and the plan was to try to initally use the 2 old 50A VESCs in dual mode. I knew they were different versions and one of them had the DRV problem but my hope was that I could run them in BLDC mode and be fine.