Yamaha (YPJ) cross core \ cross connect speed limit mod sold in Japan

bikelifelite

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Not affiliated in any way but with the issues I saw others having with de-restricting Yamaha bikes with the hub mounted speed sensor, I thought I'd share what I've found while researching. BTW I have no idea if this stuff works so some feedback from someone more knowledgeable would be great. Sorry but if you want bother with the info, ya gotta bother with Google translate. My tablet is garbage and I don't have the time to copy and paste it all.


Additional link to the PAS category Brace. This one includes sprockets.

 
Hi,

Just a quick glance at the text, but that person is selling a lot for more typical Yamaha bike sold in Japan (the PAS line, not the YPJ line). Those trends to have an optical or magnetic sensor on the outside of the hub. This means they are easy to defeat if you just change that ring with one which has fewer magnets or holes. (you can also just change the gear size from the motor to the chain...)

The higher end bikes like the YPJ line use a bit different and more sophisticated of a system.
 
Update... There are mods sold for the YPJ line (an Yahoo Japan, etc.), they consist of just a different magnetic disc that goes on the axel. So if the normal disk changes polarity 16 times, the modified one changes polarity only 8 times so that the bike will think it is going half the speed (and this keep up assistance to twice the speed). I'm sure these work fine, but they will screw up your speed display, obviously.
 
I have a 2021 Crossconnect (purchased in US) and want to understand how the hub mounted speed sensor works. I have gathered some pictures and diagrams, however, more pics would greatly help me. The pickup assembly (#17 in diagram) is a Hall sensor with three leads, a positive, ground, and signal wire. There is a coil in the pickup, which when energized creates a magnetic field which is changed when a magnet passes by it. That change in the magnetic field induces a current in the signal wire which is sent to the controller in the motor assembly (see wiring diagram). What I don't know, or understand, is where the magnet(s) are. I show two photos of a 2020 Civant hub from another thread, and think that my speed sensor assembly is the same. The third photo is a pic of my Crossconnect bicycle (the poor quality one!). In the second photo there are 4 items laying against each other, and I think the 3rd item from the left is part #16 (in catalog), the magnet component. It has evenly spaced tabs around it which may be steel, or even hold small magnets on them. Can someone explain this part to me, or tell me I'm completely off base here? I would like to see a picture of the magnets (or steel slots) that rotate with the wheel that induce a signal in the Hall sensor. A lead to a parts manual and/or service manual for the Crossconnect PW SE motor would be greatly appreciated as well.
 

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Hi,

At least for the Yamaha YPJ series, the magnet is a small rotating disc in as seen on photo 7 in the link below.

For the YPJ series, this disk just has one physical magnet, but the way it is magnetized, it simulates a series of magnets passing.


 
Hi,

At least for the Yamaha YPJ series, the magnet is a small rotating disc in as seen on photo 7 in the link below.

For the YPJ series, this disk just has one physical magnet, but the way it is magnetized, it simulates a series of magnets passing.


Shiruba, many thx for helping me to understand! For completeness, you refer to YPJ series. Is this the Japanese version of the current 250W motor (and it’s variations) that is sold in the USA?
 
Shiruba, many thx for helping me to understand! For completeness, you refer to YPJ series. Is this the Japanese version of the current 250W motor (and it’s variations) that is sold in the USA?
Oops, I just read “all about e-bikes in Japan.
 
I have not been able to find available genuine Yamaha parts from either dealers in the US, or Yamaha Corporate in Cypress, CA. The part number for the magnet I would like to buy is X1M-8352Y-00. Is it possible to purchase genuine Yamaha e-bike parts in Japan? What is merukari? (Thank you for your patience!)
 
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adeptpowersports.com appears to have part # X1M-8352Y-00 in stock for $16. My Yamaha CrossCore has a sensor ring with 8 sensors not evenly spaced around the ring. There are 4 groups with 2 in each group. I am contemplating drilling-prying out two groups of sensors to see if (1) my bike still works, (2) the display shows half speed, and (3) if the speed limit is removed. The sensor ring is mounted on the rear wheel hub near the brake.
 
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