Recent content by dr_lulz

After using it not too much recently i want to sell my tuned Berg Viper DH bike. I put lots of effort into the build quality of the bike. Everything is rugged and components are high quality. Components: - Berg Viper DH Frame - Mxus 3k Turbo 4T Motor in 19" Motocross - Battery 19S7P = 79,8V...

great find, i will mod mine too :bigthumb:

Lately i have tested my r4875g2 for max power. Somehow i am not able to go above 58A :?: If i send the CAN command for setting current to 65A i end up with 1A or less. At first i thought it is an integer overflow somewhere in the CAN code but the value that is send to the PSU is 58*20 = 1160...

in case anyone cares, this is how my PSU looks now: i soldered 8mm bolts for battery and attached screw terminals for 2.5mm^2 230v cables. Hopefully enough for 70A for several hours :mrgreen:

Today i was able to test CAN communication on my R4875G1. So far it works more or less out of the box. :thumb: It pulls 4w standby. Fan is more or less silent. If current is set to 0A the voltage starts dropping slowly and the fan ramps up for no reason. Hopefully this changes with a battery...

Has anyone tested the CAN code for other models like r4875g1? I would prefer this model because of the 4000w but if CAN controlling does not work, its useless :confused:

latest update: Right now i am working on street legalization with german TÜV + electric braking + legal lights

i have used lead free solder. But i would recommend to use leaded because i had to redo a few joins ....

i have used an old cooking plate, set it to 400°, put the strip and copper wire on it and then simply soldered it

hehe, i have wrapped every parallel pack in 1 layer of kapton. Between the packs are: shrinkwrap - kapton - kapton - shrinkwrap. Also the batterys are glued together so nothing moves Hopefully this is enough :flame:

Btw during testing i found that my mxus 3k seems to run very uneven. I was expecting a little more quality for its price. See in the video: (The chain is shaking!) https://streamable.com/s/2xz6s/qdpxnv

The frame is 17". There is only one size :(

another update! Bike is almost done, was running it on testbench a few times with limited current. I can already feel the power :twisted: Here a few more pictures that i made during the build Battery: 6 mm^2 copper, good for short 100A bursts (i hope) arduino spot welder Kelly...

anyway there was some progress the last month i designed the battery box mount 3d printed prototype and also made a backplate for the torque arms including the derailleur mount (no CAD pictures, sorry) both custom laser cut out of 4mm steel and 10mm aluminum mounted: (not yet final)...

well, for me peak means maybe 10-15 sec MAX. In general voltage should be as high as possible to reduce losses. I dont care about the topspeed i am planning to go street legal here in germany so i will be limited to 4kw nominal power (not peak!) and 45km/h anyway. unfortunately last week my...