I have just modified my Samebike LO26-II 500w with a single front chainring, going from the original 42t to a 52t. Plus a longer chain of course. All works ok except that the pedal assist doesn’t seem to cut in in the higher gears 5-6-7. Thumb throttle works ok in those higher gears, but not the pedal assist. Going down to lower gears it works ok but there’s no assistance on the higher gears. It’s defo de-restricted in the menu (top speed is set to 100km/h). To be honest it’s such a long time since I last rode it I can’t remember if this fault existed before I did the chainring mod. Any suggestions please?

I have just modified my Samebike LO26-II 500w with a single front chainring, going from the original 42t to a 52t. Plus a longer chain of course. All works ok except that the pedal assist doesn’t seem to cut in in the higher gears 5-6-7. Thumb throttle works ok in those higher gears, but not the pedal assist. Going down to lower gears it works ok but there’s no assistance on the higher gears. It’s defo de-restricted in the menu (top speed is set to 100km/h). To be honest it’s such a long time since I last rode it I can’t remember if this fault existed before I did the chainring mod. Any suggestions please?

Try pedalling faster in whichever gears it works to see if it cuts out at a particular speed. The pedal sensor doesn't know what gear you're in. The only things that can stop it from working is either a max speed cut-off or it's slipping, but it would be more likely to slip in a low gear when pedalling fast, so that's not very likely to be the cause.

Are you hitting the maximum speed of the hub motor ? -looks like top speed around 20 mph ?

 

Edited May 13, 2025May 13 by Peter.Bridge

With the back wheel in the air the motor will spin up to 22mph. I’ve just replaced the PAS sensor and it’s the same, pedal assist just dies when you change from 5th to 6th, but using the throttle will still give you a push at that speed, so I’d expect the PAS should still be working?

With the back wheel in the air the motor will spin up to 22mph. I’ve just replaced the PAS sensor and it’s the same, pedal assist just dies when you change from 5th to 6th, but using the throttle will still give you a push at that speed, so I’d expect the PAS should still be working?

If you change into 6th gear at 15mph does it still give you a push ? I don't think he controller knows what gear you are in

With the back wheel in the air the motor will spin up to 22mph. I’ve just replaced the PAS sensor and it’s the same, pedal assist just dies when you change from 5th to 6th, but using the throttle will still give you a push at that speed, so I’d expect the PAS should still be working?

You need to establish at what speed it cuts out. Is it consistent or is it a different speed each time. You need to test with at least a bit of load on the motor, otherwise it'll overrun.

Gear cable wear on the sensor flex?? only shorting when the cable is under max gear tension??

 

Its the only theory i can muster??

 

trace all cable , flex routes carefully mm by mm with a bright light perhaps? but you must have done so already ??