Russell
1 MW
On my first front motor E-bike conversion I did what many people do and filed those pesky protrusions clean off so the torque washers supplied would fit flush with the dropouts. Others people use lockwashers or other washers to fill the gap, ebikes.ca even has special C-washers to do the job.
On my second build I wanted to keep the lawyer lips intact should I wish to convert back to a normal front wheel or someday sell the bike. I like the torque washers/ anti-spin washers or whatever you call them washers provided with many kits because they are nice thick steel and enclose the entire axle unlike the fork dropouts so I wanted to use them. The solution actually was quite simple, grind down the edges of the torque washers so they fit within the lawyer lips.
Here's a picture of a torque washer with the area to be removed shown in black. Note that this is not the washer used on my bike, this is an extra washer for a 14mm axle for demonstration only. To make this work the axle and the washer need to be 12mm like the Bafang motor installation shown in the last picture. A 12mm washer has more material around the area to be filed down plus it will sit higher in the dropout compared to a 14mm axle washer.
I had to remove the material from the washers with hand files which took some time. I wanted a precise, snug fit so it also took a lot of filing and test fitting to get it just right. The results however were worth it. I put the front wheel in the dropouts and press down on one side then tighten the nut which squeezes the washer just past the lawyer lips then I repeat for the other side. It's a bit hard to see in the picture but the washer is behind the lawyer lips which actually make a cup around the washers adding a little extra strength and resistance to spinning.
-R
On my second build I wanted to keep the lawyer lips intact should I wish to convert back to a normal front wheel or someday sell the bike. I like the torque washers/ anti-spin washers or whatever you call them washers provided with many kits because they are nice thick steel and enclose the entire axle unlike the fork dropouts so I wanted to use them. The solution actually was quite simple, grind down the edges of the torque washers so they fit within the lawyer lips.
Here's a picture of a torque washer with the area to be removed shown in black. Note that this is not the washer used on my bike, this is an extra washer for a 14mm axle for demonstration only. To make this work the axle and the washer need to be 12mm like the Bafang motor installation shown in the last picture. A 12mm washer has more material around the area to be filed down plus it will sit higher in the dropout compared to a 14mm axle washer.
I had to remove the material from the washers with hand files which took some time. I wanted a precise, snug fit so it also took a lot of filing and test fitting to get it just right. The results however were worth it. I put the front wheel in the dropouts and press down on one side then tighten the nut which squeezes the washer just past the lawyer lips then I repeat for the other side. It's a bit hard to see in the picture but the washer is behind the lawyer lips which actually make a cup around the washers adding a little extra strength and resistance to spinning.
-R
