vax
100 W
Hello folks, I haven't been here for some time and this will be my KTM build thread.
I purchased this bike 10 years ago or so, previous owner had blew the engine, removed cylinder and then stored the bike outside. Of course the rain did fill up the engine eventually and when I got the bike the engine was rusted solid.
I converted the bike to YX140 chinese pit bike 4-stroke, this involved lengthening the frame a bit so that the engine would clear the front tire.
I used that bike for a number of years as my daily driver at my summer home, which was at small island of Prangli, Estonia (see youytube videos, it's really cool place, and you could drive whatever you like, because of no police involved). However I didn't like the "tractorness" of that 4-stroke engine, vibration and general slugishness and it also developed nasty knock, which I couldn't figure out. So, when I saw used QS 138 90H kit on sale, with EM200 controller, complete harness with throttles, DC-DC inverter and so on, it didn't need long and hard thinking. That 4-stroke lump has to go and make room for zippy QS138.
This is how it looks right now:
Now, the batteries.
I happen to have a shitload of used 8000mAh 5S LiPo packs, which I "recycled" from my previous job. Most of them are really in great shape, some of them are slightly undervoltage, but also curable. Some are almost dead. I think I have 50pcs of them or more.
Also, being aware of dangers involving LiPo batteries, I want to build a safe system so I don't burn my house down. So, I had this idea of dividing the battery pack into smaller sub-packs, each in separate aluminium enclosure and having it's own 5S BMS-es inside those modules. Or, at least making PCB-s inside the modules, that would connect separate LiPo batteries together with balance plugs and having thicker copper busbars soldered onto PCB trails - and then having external connector for central BMS harness.
I purchased this bike 10 years ago or so, previous owner had blew the engine, removed cylinder and then stored the bike outside. Of course the rain did fill up the engine eventually and when I got the bike the engine was rusted solid.
I converted the bike to YX140 chinese pit bike 4-stroke, this involved lengthening the frame a bit so that the engine would clear the front tire.
I used that bike for a number of years as my daily driver at my summer home, which was at small island of Prangli, Estonia (see youytube videos, it's really cool place, and you could drive whatever you like, because of no police involved). However I didn't like the "tractorness" of that 4-stroke engine, vibration and general slugishness and it also developed nasty knock, which I couldn't figure out. So, when I saw used QS 138 90H kit on sale, with EM200 controller, complete harness with throttles, DC-DC inverter and so on, it didn't need long and hard thinking. That 4-stroke lump has to go and make room for zippy QS138.
This is how it looks right now:
Now, the batteries.
I happen to have a shitload of used 8000mAh 5S LiPo packs, which I "recycled" from my previous job. Most of them are really in great shape, some of them are slightly undervoltage, but also curable. Some are almost dead. I think I have 50pcs of them or more.
Also, being aware of dangers involving LiPo batteries, I want to build a safe system so I don't burn my house down. So, I had this idea of dividing the battery pack into smaller sub-packs, each in separate aluminium enclosure and having it's own 5S BMS-es inside those modules. Or, at least making PCB-s inside the modules, that would connect separate LiPo batteries together with balance plugs and having thicker copper busbars soldered onto PCB trails - and then having external connector for central BMS harness.
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