Hi folks, I'm trying to find why my older Dutch town bike (with slightly newer aftermarket kit) has died.
It look like the fault is down the yellow phase transistor in the hub.
I swapped the wiring around, the fault stayed with the transistor so it's not a wiring issue.
I removed the yellow signal wire at the hub end and checked the transistor, even with no output wire connected I get zero volts (the 4.5V feed and earth check out ok) - it's dead Jim !
Tests were done with a charged 36v battery (showing 38v), the wheel has been opened up and I'm turning the motor backwards to check the voltages on the phases - it's the way I usually do tests...
It's a basic old system and getting parts out here (Portugal) is difficult so I'd like to try fixing it using what I have here.
The harness is old-school with block connectors not waterproof bullets so it's easy to check voltages.
I have a scrap hub motor from a 24v system (scrapped due to old age and wrecked motor cable) but I think the hub transistors all work on 4,5v so they should be swappable'ish.
My question: will a transistor from the scrap hub be compatible with the hub currently on the bike - if so I'll swap one from the old hub to new.
I picked up a 36v controller and display "working well - honest guv" as a spare, It turns on (with just battery and display connected, no PAS etc) but then turns off again after a few seconds. Is this normal ?
When it's on, I'm only seeing 2.5v on feeds to the PAS, brake cutofffs etc when I'd expect 4.5v
I think this means it's dead but maybe I've missed something?.
It's 36V/48V compatible, I can get into the P settings but have no manual to decode what I see, my only hope is it's in 48V mode and is seeing the charged 36V battery as below LVC - any way to check?
Background info possibly relevant : The problems started when let a friend of a friend (now known to be an irresponsible fool) borrow the bike, he has snapped the rear rack which has strained the harness in that area but I don't see how that could be related to a failure in the front hub...
I have time and a pile of bits, asking here in the hope I can patch a working system together somehow...
All suggestions (apart from "buy a new..") welcome
It look like the fault is down the yellow phase transistor in the hub.
I swapped the wiring around, the fault stayed with the transistor so it's not a wiring issue.
I removed the yellow signal wire at the hub end and checked the transistor, even with no output wire connected I get zero volts (the 4.5V feed and earth check out ok) - it's dead Jim !
Tests were done with a charged 36v battery (showing 38v), the wheel has been opened up and I'm turning the motor backwards to check the voltages on the phases - it's the way I usually do tests...
It's a basic old system and getting parts out here (Portugal) is difficult so I'd like to try fixing it using what I have here.
The harness is old-school with block connectors not waterproof bullets so it's easy to check voltages.
I have a scrap hub motor from a 24v system (scrapped due to old age and wrecked motor cable) but I think the hub transistors all work on 4,5v so they should be swappable'ish.
My question: will a transistor from the scrap hub be compatible with the hub currently on the bike - if so I'll swap one from the old hub to new.
I picked up a 36v controller and display "working well - honest guv" as a spare, It turns on (with just battery and display connected, no PAS etc) but then turns off again after a few seconds. Is this normal ?
When it's on, I'm only seeing 2.5v on feeds to the PAS, brake cutofffs etc when I'd expect 4.5v
I think this means it's dead but maybe I've missed something?.
It's 36V/48V compatible, I can get into the P settings but have no manual to decode what I see, my only hope is it's in 48V mode and is seeing the charged 36V battery as below LVC - any way to check?
Background info possibly relevant : The problems started when let a friend of a friend (now known to be an irresponsible fool) borrow the bike, he has snapped the rear rack which has strained the harness in that area but I don't see how that could be related to a failure in the front hub...
I have time and a pile of bits, asking here in the hope I can patch a working system together somehow...
All suggestions (apart from "buy a new..") welcome
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