C washers from Ebikes-Ca pictures replaced

[dogman dan]

These are the item you need to propery fit a motor wheel onto a set of forks with deep quick release cups, especially alloy forks.

I am really impressed with the quality of these little jewels. Made from some fairly hard steel, and very nicely cut. Not stamped out of a sheet of mild steel like ordinaly washers. The following picture is pretty poor, but sort of shows the way the c washers fit into the cup beautifully, filling the space. Taking a Tourqe washer and grinding it down can work, but then the tourqe washer gets too weak, and on alloy forks, it would break the forks anyway. So get a couple of these, and some tourqe arms if you plan to mount a motor on a set of suspension forks.

Editing in some new pictures at this point, in 2012. This one shows the axle, in an alloy dropout that has a deep cup for a QR hub. The dropouts were filed deeper to get the axle center in the center of the dropout.


Now the C washer installed into the cup. It really works great for filling in the cup. Now a washer or nut will bear on the dropout cup, which will not press on the forks unevenly. Uneven pressure on the forks will crack them, or let the axle spit out of the dropout.




See the upcoming Tourqe arms from Ebikes-ca review for more on the hub fiting process.

Edit. Pics got lost for this thread. Here is what the c washer looks like. It's the one on the upper left. It fills the space on a fork that has a cup for QR hubs. The typical stock bicycle axle nut is on the lower right. The larger nut and washer are for a hubmotor with a 14 mm axle. Stock axle is 10 mm.
This is a 10mm nut in the recessed cup on the suspension fork dropout.


The problem is, the recessed cup in most aluminum alloy suspension forks, or even some steel forks is too small. Using the big nut and washer for the hubmotor means that there will be a gap left under the nut and washer. This gap can cause the nut to loosen, or it will tend to pry the dropout open, cracking the alloy. Then the wheel falls off at 25 mph. Ouch!

This pic, though hard to see, shows a small air gap under the nut. (pic missing)

And here, the c washer fills the void so the nut is fully supported by the shoulder of the dropout. If the cup was much deeper, it would have to be filed down. If there is still a gap after the c washer is in place, the cup is too deep. Often on alloy forks, the shoulder around the cup is not flat, so you can't have the washer or nut bearing on that. You want to have all the pressure on the c washer only.

Sorry about the lost pics. My copies were also lost in a hard drive that died. Here at least, is a pic of the C washer.

 

[Russell]

The problem is most likely because the C-washers from ebikes.ca are for motors with 12mm axles and the 9C has a 14mm axle. I had the same problem with grinding down the steel torque washers, it works great for 12mm but not for 14mm. :?

-R

 

[dogman dan]

No , the c washers are perfect. They work fine with either 12mm axles or 14 mm.

It was the fork that had a oil drain bolt in a bad location. Just the wrong fork to try to use with this hub motor, but you are correct that the larger axle and larger nut interfered with the drain bolt. The same forks can take my Aotema motor no problem. (12 mm axle) Come summer, when getting home fast in hot weather is nice, I'll start running the aotema.

 

[Russell]

No , the c washers are perfect. They work fine with either 12mm axles or 14 mm.

It was the fork that had a oil drain bolt in a bad location. Just the wrong fork to try to use with this hub motor, but you are correct that the larger axle and larger nut interfered with the drain bolt. The same forks can take my Aotema motor no problem. (12 mm axle) Come summer, when getting home fast in hot weather is nice, I'll start running the aotema.

I stand corrected. Justin's description says they're for 12mm but after thinking about it I guess there's no reason they shouldn't work with a 14mm axle. My ground down torque washers do however work better with a 12mm axle since there is still plenty of material left afterwards. They wedge in just above the QR lawyer lip protrutions and work great for the 12mm axle on my Bafang.



For my 9C I may order the C-washers from ebikes.ca if I buy something else too.

-R

 

[dogman dan]

After homebrewing some c washers from lockwashers once, I decided to give the C washers a try. They really work great and fit the cup in the fork perfectly.

But yes, grinding down some torque washers works well too.

 

[RTLSHIP]

C washers seem pretty cool. I had a problem with the "lawyer lips" or ridges on the fork drop outs. 2 previous solutions: 1. a torque arm set up or 2. grind down the outer part of regular lockwashers. I combine both.
These C washers are a practical solution provided they go on flush.

 

[dogman dan]

For those that don't want to break out the dremel or files, these are good. They really fit nice and give me the courage to run alloy forks. Now if we can just get the motor manufacturers to supply washers that actually fit bikes...... I suppose I'm dreaming, those chinese bikes the motors are designed for may not have any lawyer lips. Only the ones they send us need em.

 

[RTLSHIP]

I used a Dayton type buffer and a sander. Gotta use pliars to hold washers. hot

 

[RTLSHIP]

I tried a 3/8" wrench, slightly grinded down. Didn't work. Torque washers don't work because the metal is stripped. Even if I hammer back to shape it's still too soft of a metal. My previous torque arm workedbut was getting "soft".
Gave it away. I'm shopping for something sturdy. maybe ebike-ca

 

[GrayKard]

I bought 2 of the C washers and 2 of the spacer washers when doing my build. The C washers were for the lawyers lips and the spacers would be used if I had interference after installing the freewheel. (I was installing both a front and a rear hub on the bike.)

Well after doing a few test fits I could see that I didn't need the spacers. I then realized they were the same size as the C washers. So instead of using the C washers to deal with the lawyers lips I put the spacers there.

The result is that if the axle nuts happen to get a little loose the axle can't slide out as it hits the spacer washer which is inset into the lawyers lips. Just a little extra bit of protection. You could reverse the C washer with the open side up to get the same effect but I wonder if losing that extra contact area above the axle would be a problem.

The down side is that on the wire side you would have to remove connectors to get the spacer washer on there but if you use the C washer you wouldn't have to do that.

Gary

 

[dogman dan]

My latest motor from E-bike kit, had a nice suprise with it. similar spacer washers that fit perfect into most suspension fork cups. Still would have to deepen the alloy dropout, but the washer shows exactly the line to cut to. Free in the kit from Jason. Pretty cool. Easy to cut into a c if you need the space for an along the axle wire (clyte or aotema).

Justins washers allow the axle to be installed without deepening dropouts if that is your preference. that is why they are slightly thinner on the bottom.

Edit, duhh, I just realised the spacer washers must be for using the rear motor with a wider freewheel. Nevertheless, they are a good alternative if ordering from Ebikekit anyway.

 

[Cold-E-Commuter]

dogman, are you sure these c-washers are steel? I have a set and a magnet did not work on them. I agree that they fill the lawyer lips from a quick release hub on a suspension fork wonderfully but I think the ones I got are aluminium. Also with a tourque arm from e-bikes.

 

[Zoot Katz]

dogman, are you sure these c-washers are steel? I have a set and a magnet did not work on them. I agree that they fill the lawyer lips from a quick release hub on a suspension fork wonderfully but I think the ones I got are aluminium. Also with a tourque arm from e-bikes.

They're stainless steel.

 

[dogman dan]

One of those facts you know, but will never quite understand. Magnets don't stick to stainless steel. I loathe stainless steel screws that the magnetic screw gun tip won't work with. You get so used to the magnet driver, then it doesn't work and huh?

 

[RTLSHIP]

I may give a C washer a try. I've been using Ebike brand torque arms on both Aotemas.
They are called "universal" because the square part of axle is the same on both 12 mm and 14mm axles.
Anyways, this ebike torque arm failed in that the axle turned over in it. At this point I'm considering a new axle as there has been alot of grinding on the threads.
Can somebody explain whether a "C" washer will hold this axle in place? Or is a new axle needed? both?
The tip of those ordinary stock torque washer (pictured above) isn't wide enough to cover the width of the fork drop-outs.

 

[mwkeefer]

Dogman,
After placing the C washer into the cup, all that remains is finding some normal steel washers (don't need to be keyed) to build up which will fit within the space (the hex adjustment bolt on the pre-load) and then torque it down
-Mike

 

[amberwolf]

Can somebody explain whether a "C" washer will hold this axle in place?

All the C washer is for is to fill the space in some dropouts (especially alloy suspension forks) so that all the washers and torque arms in the stack all sit perfectly flush and perpendicular to the axle. AFAIK the C washers aren't intended to actually secure anything in place.

 

[RTLSHIP]

How complicated to swap out hub axles? My hub axle is under 9.5 mm as it has been stripped , mangled etc. I'm using tape to would add bulk to the axle. Once an axle is worn down, it will slip out of the grasp of the torque arm 10 mm slot. The torque arm doesn't move; rather, the axle gets loose. It can happen again.
The bike is still ridable as I have opted to add tape to the axle. Also, I had to take hammer and vise grips to the torque arm
to get back original form.

 

[dogman dan]

A bit late to reply to that question now, but if anybody else has the same problem, pinch dropouts would be the best solution. Here is my version.