Has anyone else had pas rain power cut out issues before?

mags2

Pedelecer
May 20, 2018
36
2
UK
I got a yosepower kit and until now never had to use it in heavy rain. I don’t have a throttle and the connector is covered plus the display seemed fine. It was like it didn’t pick up the pas properly and kept repeatedly starting and cutting out the motor. It was fine later on the way back.

Everything else should be pretty well protected so im wondering if water gets in the pas or breaks perhaps?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,992
8,173
60
West Sx RH
Moisture once it affects the 5v line can cause issues, the brake cut outs are usually fine. Any issue might be more prevalent with the PAS sensor as positioned on the BB gets far more road spry directed at it, particularly where the cable enters or the joint of the unit. Most tend to be sealed though may not always prevent moisture ingress.

In the past I have had about three issues with moisture ingress, one was a throttle issue with the Julet having moisture enter and the other two were PAS related. All occurred on the old Oxydrive kit which had integrated battery/controller, not had an issue with any other bike.
 
Last edited:
  • Informative
Reactions: mags2

mags2

Pedelecer
May 20, 2018
36
2
UK
Yeah it's likely the pas so i wonder how do i go about giving it extra waterproofing?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,992
8,173
60
West Sx RH
Yeah it's likely the pas so i wonder how do i go about giving it extra waterproofing?
First check inside the PAS wire connector ( if a julet one), if it is exposed to the weather/water spray. Then you have to look at the cable entry to the sensor to see if it is likely moisture can enter, once dry and PAS is working you will need to add some sealant around the entry. Moulding sugru putty might work or try a butyl sealant.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,992
8,173
60
West Sx RH
Moisture tell tale in Julet's is Green oxidising tracks between on or between pins.
 
D

Deleted member 25121

Guest
Perhaps the gap between sensor and magnets is too great causing marginal pickup when there's water in the gap?
 
  • Like
Reactions: Nealh

Sturmey

Esteemed Pedelecer
Jan 26, 2018
532
302
67
Ireland
I got caught out today with a rear hub Bafang PAS (with no throttle) about 7 miles from home. I had to pedal the whole way home. Anyhow, after some probing, the PAS sensor (kingmeter with led) was found to be faulty. I took it out and dismantled and removed its cracked sealent and you could see white corrosion marks on small PCB with magnifying glass. Anyhow after drying out, it seems to work. I put it back and resealed. The only sealent I had in the house was clear builders silicon so hopefully it will work for another while. The sensor has a hard life located on the bottom bracket and gets constantly drenched. The roads here are permanently wet for the winter.
 
Last edited:

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,992
8,173
60
West Sx RH
My Norco 700c which is my most used bike used for commute and errand running locally is ridden many times for 5 days of the week in all weather, for about 5 years have used the same pedal sensor without issue.
End of the day the PAS sensor is a cheap part so if in doubt keep one as new spare and swap it out if a fault occurs.
 

Sturmey

Esteemed Pedelecer
Jan 26, 2018
532
302
67
Ireland
My Norco 700c which is my most used bike used for commute and errand running locally is ridden many times for 5 days of the week in all weather, for about 5 years have used the same pedal sensor without issue.
End of the day the PAS sensor is a cheap part so if in doubt keep one as new spare and swap it out if a fault occurs.
The small led located towards the top of the unit seems to have been the weak spot in my case as its legs were black with corrosion. The cable entry was facing downwards and looked dry.
 

Advertisers