Where can I get a split pas ring ?

KirstinS

Esteemed Pedelecer
Apr 5, 2011
3,195
878
Brighton
Hiya

Anyone know of a uk source for the easy install split PAS ring ?

And would it matter if my old one has fewer magnets than the new one ?

Thanks
Kirstin
 
D

Deleted member 4366

Guest
Why do you want a split one? It doesn't take much to fit a normal one. Your controller will work with more magnets, but the split ones (it seems) only work on one side, so you have to make sure that you get the correct hand.
 

Swytch Bike

Official Trade Member
Sep 10, 2014
153
68
30
Why do you want a split one? It doesn't take much to fit a normal one. Your controller will work with more magnets, but the split ones (it seems) only work on one side, so you have to make sure that you get the correct hand.

The split PAS can actually work on either side - although you're right d8veh they are designed to be used normally on the LHS (out of the way of the gears) with the sensor position like in the attached video. This means the magnets on the disc are passing from left to right across the face of the sensor as you pedal forwards and this creates a positive voltage.

If you put the pas on the RHS with the sensor the same way up, then you need to pedal backwards to have the magnets passing from left to right across the face of the sensor and thus get the positive voltage. The quick way to solve this is just to fit the sensor upside down onto the bike so now the magnets pass from left to right across the face of it when you pedal forwards :)

It's all in the physics, got to love Fleming's left hand rule of magnetism! :p

(Actually another alternative solution is to swap the wires around going to the controller, this changes the polarity of the output voltage generated)

If you're handy with bikes and have the right tools then fitting a normal PAS is fine - but the split PAS is great for people who find removing the crank etc. difficult. As you can see from the video it's dead easy to fit, and makes the whole conversion process accessible to someone who just wants to "plug-n-play"

 

morsmana

Pedelecer
Jan 12, 2015
40
3
59
It amazes me that after all this time we are still talking about this fundamental element of all pedelecs. Most of us mere mortals will convert one or a very few bikes, but look at all the traffic there is on the problems of fitting the magnets to the crank gears side ( the easy fit split system supplied with the oxy kit for example is designed to fit the right hand side) or bodging the sensor to fit the non crank left hand side, because there's not enough clearence on the right hand side. Of all the plug/ sockets on the kit, if this one alone was reversible by 180 the problem goes away, no cutting wires, no bodging the sensor mounting, no gluing magnet rings on crank gears, replacing bottom brackets etc etc..
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,669
fitting the pedelec sensor is one of the trickiest steps in converting a bike with hub motor. The split ring is an OK design, not meant for fitting on the non-drive side though, because it's quite easy to knock it and kill it with your left shoe.
There are a couple of specifically designed pedelec sensors for fitting on the non drive side:



from Woosh:
 
D

Deleted member 4366

Guest
The split PAS can actually work on either side - although you're right d8veh they are designed to be used normally on the LHS (out of the way of the gears) with the sensor position like in the attached video. This means the magnets on the disc are passing from left to right across the face of the sensor as you pedal forwards and this creates a positive voltage.

If you put the pas on the RHS with the sensor the same way up, then you need to pedal backwards to have the magnets passing from left to right across the face of the sensor and thus get the positive voltage. The quick way to solve this is just to fit the sensor upside down onto the bike so now the magnets pass from left to right across the face of it when you pedal forwards :)

It's all in the physics, got to love Fleming's left hand rule of magnetism! :p

(Actually another alternative solution is to swap the wires around going to the controller, this changes the polarity of the output voltage generated)

If you're handy with bikes and have the right tools then fitting a normal PAS is fine - but the split PAS is great for people who find removing the crank etc. difficult. As you can see from the video it's dead easy to fit, and makes the whole conversion process accessible to someone who just wants to "plug-n-play"

Are you sure about all that? Did you test that what you said is true for the split disc type?

All the ones I've seen use hall sensors, so you can't reverse any wires. They have three wires too, so which ones would you reverse?

The ones that I've seen with a removable segment held on with a big circlip have a double hall sensor arrangement so that it works in the same direction regardless of which way up the magnet disc, so if you have a left handed one, you can't use it on the right hand side by flipping the magnet or reversing any wires.

The cheaper ones with a single hall sensor can be fitted either side by flipping the magnet disc. I haven't seen a splittable one like that.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
10,771
4,094
57
West Sx RH
The split one 12 magnets I have with the Oxygen kit was a RH one.
 

Swytch Bike

Official Trade Member
Sep 10, 2014
153
68
30
Are you sure about all that? Did you test that what you said is true for the split disc type?

All the ones I've seen use hall sensors, so you can't reverse any wires. They have three wires too, so which ones would you reverse?

The ones that I've seen with a removable segment held on with a big circlip have a double hall sensor arrangement so that it works in the same direction regardless of which way up the magnet disc, so if you have a left handed one, you can't use it on the right hand side by flipping the magnet or reversing any wires.

The cheaper ones with a single hall sensor can be fitted either side by flipping the magnet disc. I haven't seen a splittable one like that.
Hi d8veh,

Yep I promise you the PAS we supply can work on either side of the bike, just by swapping the orientation of the sensor. It activates when the magnets move across it's surface, but only in one direction. So if you have to pedal backwards to get it to activate, then you just need to flip the sensor 180 degrees, and then it'll activate when you pedal forwards.

If you really don't believe me I'll make you a video and upload on YouTube to demonstrate ;)
 
D

Deleted member 4366

Guest
Hi d8veh,

Yep I promise you the PAS we supply can work on either side of the bike, just by swapping the orientation of the sensor. It activates when the magnets move across it's surface, but only in one direction. So if you have to pedal backwards to get it to activate, then you just need to flip the sensor 180 degrees, and then it'll activate when you pedal forwards.

If you really don't believe me I'll make you a video and upload on YouTube to demonstrate ;)
Some of your listings show the split disc with the double hall sensor, which are handed. Other listings show the unsplittable discs with te single hall sensor, which are not handed. Which ones are you referring to? OP was asking for your split type. I just fitted one to a bike yesterday. I checked, and it's definitely handed.
 

jonathan75

Esteemed Pedelecer
Apr 24, 2013
782
207
Hertfordshire
Slighty off topic but does anyone know if this PAS install looks correct please? I'm getting no power from the bike using it, and the red LED on the PAS sensor only flashes when I turn the cranks backwards. Thanks.
upload_2015-5-11_14-21-45.jpeg
 
D

Deleted member 4366

Guest
You've fitted the magnet disc the wrong way up for that side. If it has a single hall sensor in it, it will still give power if you pedal backwards. Double hall sensor ones are handed, so only work on the right side unless it's a left hand PAS, which yours isn't.

Do you get power when you pedal backwards on any level but zero on the display?
 
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jonathan75

Esteemed Pedelecer
Apr 24, 2013
782
207
Hertfordshire
You've fitted the magnet disc the wrong way up for that side. If it has a single hall sensor in it, it will still give power if you pedal backwards. Double hall sensor ones are handed, so only work on the right side unless it's a left hand PAS, which yours isn't.

Do you get power when you pedal backwards on any level but zero on the display?
Yes I'm getting power pedalling backwards but not forwards. D'oh! I'm not sure about zero power levels. Thanks D8veh. So you're saying this disc needs to be mounted on the right of the bike.