Ezee freewheel clutch stuck

TRRRR

10 mW
Joined
Jan 30, 2013
Messages
21
Hello, I was riding my bike today and the motor was making noise while slowing down. After some investigation it turns out the freewheel is no longer working.

I disassembled the motor in my garage and took the clutch out - cant get it to freewheel. It seems the clutch is held together with rivets and cant be taken apart. Is there any way of repairing the clutches?

I have treated the motor pretty well, generally less than 700 W. Max 1000W. About 4500 kms over one year. Is this a bit early for a failure like this?
 
I've managed to free stuck clutches in similar motors. You get a big lump-hammer and whack the wheel in the forward direction. After a few whacks, they free up if you're lucky. They were all fairly new though. I've seen other clutches stuck because of rust. You can't do anything with them.
 
Thanks guys.

The gears and the internals of the motor still look new. No water damage or rust.

d8veh, I would be tempted to try the hammer method. Are you saying you whack the tyre of the bike wheel with the hammer to free it up?
 
Thanks Ypedal, I have checked the teeth and they are fine.

I am going to try cutting a notch in the clutch disc then lodging a screw driver in the notch and hitting with a hammer. I will clamp the axle in a vice while doing this.
 
If you weaken the clutch disc by removing material from it, there's a good chance it's just going to break in use at some point, and then it will freewheel in both directions.

If that happens, and there's enough space in the motor, you might be able to use a radiator hose clamp to put enough pressure across the break to at least get home, but I wouldn't make any bets on how long the fix will last. I didn't keep using mine (past getting home) after it broke and I fixed it with a hose clamp, so I don't know how long it would have held up.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=15570&p=576368&hilit=hose+clamp+clutch+dayglo+avenger#p550415

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Em3ev sells clutch assy's. They are the V2 version.
I think I have a couple new ones laying around somewhere.
 
TRRRR said:
Thanks guys.

The gears and the internals of the motor still look new. No water damage or rust.

d8veh, I would be tempted to try the hammer method. Are you saying you whack the tyre of the bike wheel with the hammer to free it up?

Yes, whack the tyre.
 
OK, that sounds like the easy way to go, whacking the tyre without removing anything.

Are the Mac clutches interchangeable with the Ezee?
 
You may just want to ride it for awhile - I have seized many clutches and they usually free up themselves - sometimes a few miles, sometimes a 100 miles, but sometimes never. Importantly, once a clutch seizes, it never holds as well again because the clutch surface on which the rollers or sprags slide can become deformed by the jam. This can make the rollers skip and just chatter instead of grabbing (like losing traction due to a bump in the road). So - you may do okay, but ordering up a replacement might not be a bad plan, even if you wait for a convenient time to install it.

Here's a post with some notes and installation vids - MAC/BMCs/eZees are structurally all about the same and have interchangeable gear clusters. Generally only the type and placement of shim washers varies between makes and models - so note that in particular when pulling things apart.

FWIW - the gears on these big gear motors almost never fail - try searching ES for failures in the last few years. Since the switch from the early nylon gears to the tougher composites a few years back, the weak link is the clutch - not the gears (smaller gear motor still use nylon so not the same situation). The clutches jam because of over-torquing which can come from overly aggressive controllers or simple road impact. Hitting a pot hole when under heavy power causes a brief but substantial torque spike and whammo - a jammed clutch as the rollers or sprags wedge tightly between the inner and outer clutch surfaces. If you see an evil road thingie coming, back off the throttle ASAP and the clutch won't take the hit.
 
If your controller allows regen, then forcing regen braking with a stuck clutch can almost certainly free it.
Maybe not immediately, but for sure after a few rides.
I once got a second hand stuck clutch due to rust, intended to be a permanent stuck clutch to research the efficiency of regen with ezee motor.
Even that one got free after few rides...
 
Nice one, that regen idea sounds good to. I am running a grin tech phasrunner and CA3 so I am pretty sure I will be able to do the regen.

I haven't had time to try anything yet, maybe on the weekend
 
fechter said:
You might like having regen more than having a clutch.

No you will not.
After my experiment with regen on the ezee, it's just not worth it: The ezee wasn't meant to spin and deliver torque (positive or negative) all the time.
It overheats way too quickly if it doesn't have a resting period. Even just the component of the ezee constantly spinning without loading it creates significant heat via hysteresis and eddy losses because of it's small mass.
I purposely welded a clutch and drive with it for a couple of days in my hilly city. I really enjoyed the super powerful regen on one hand, but after few days, the gears melted from the gradual heat build-up: They were already soft enough from the heat build up and failed when I applied regen torque on a steep descent.
This is in addition to the NIGHTMARE of servicing the ezee motor: You have to unlace it in order to service it's internals. This means that whenever your clutch will fail,you will need almost a full day of disassembling, unlacing, and after servicing you will need to lace and true the wheel on a truing-stand. Still not convinced?
Just get a more powerful DD motor if you want powerful regen. It's reliable and won't break.
Read the thread I wrote about the experiment, which failed miserably:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=83698
 
thunderstorm80 said:
fechter said:
You might like having regen more than having a clutch.

No you will not.
After my experiment with regen on the ezee, it's just not worth it: The ezee wasn't meant to spin and deliver torque (positive or negative) all the time.
It overheats way too quickly if it doesn't have a resting period. Even just the component of the ezee constantly spinning without loading it creates significant heat via hysteresis and eddy losses because of it's small mass.
I purposely welded a clutch and drive with it for a couple of days in my hilly city. I really enjoyed the super powerful regen on one hand, but after few days, the gears melted from the gradual heat build-up: They were already soft enough from the heat build up and failed when I applied regen torque on a steep descent.
This is in addition to the NIGHTMARE of servicing the ezee motor: You have to unlace it in order to service it's internals. This means that whenever your clutch will fail,you will need almost a full day of disassembling, unlacing, and after servicing you will need to lace and true the wheel on a truing-stand. Still not convinced?
Just get a more powerful DD motor if you want powerful regen. It's reliable and won't break.
Read the thread I wrote about the experiment, which failed miserably:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=83698

I want to add one important note to what I wrote:
The ezee is a wonderful motor, if you use it according to how it was designed to be used.
It's small, yet still powerful, and it can provide impressive torque output, but only for a limited amount of time. It is an assisting motor by design, and this is why it has a freewheel clutch so it can rest and cool off.
I considered the option of permenantly locking it and making it de facto "DD" motor by using metal gears, but then the stator-coils are still trapped deep inside and cannot transfer their heat outside fast enough, require you to find a cooling solution which mechanically just isn't possible at all. (ATF fluid won't work)
And there is no temperature sensor inside that motor either.
So to conclude - just use it within the specs, and if you run it with Phaserunner and program it correctly (you can ask me how - I already have the experience), it can last a very long time. If the clutch seizes, just apply regen torque and it will be set free immediately, or after a very short time.
 
Ypedal said:
unless you have a different model, all the one's i've had on hand can be opened without unlacing.

http://ypedal.com/ezee.htm

The new motors that come with the modern cassette freehub instead of the standard freewheel-threads require unlacing in order to open the cover. The older ones do not.
 
Very old thread, but as this just happened to me (clutch jammed) after I noticed that 1. my battery wasn’t actually depleting and my ride to work got really a lot harder. Anyway, as one ingenious poster mentioned getting out the hammer and freeing the hub by giving it a whack or 10, so after trying that without success, it got me thinking I could hang my back wheel out the door of my car (bike still attached) and get going fast and drop the back tire onto the pavement, luckily my keen spider sense thought that was a little crazy (at least initally) so I instead decided to take the bike out into the street in front of my house . I then lifted the back wheel off the ground and ran really really fast....well, I’m 55 years old so it was really really fast for me, and once I hit Ussain Bolt speed, I dropped the rear wheel onto pavement, and voila, free hub. Actually to be truthful, I jogged at slightly faster and faster speeds several times until it freed at my near top speed of 12.372 mph. (Or 20.543 kph). My neighbors probably thought what my wife already knows, that I’m a moron , but the bikes fixed. I didn’t even break my hip. Hopefully this helps someone else not to hang their Ebike out the window of their car at terminal speed in an attempt to free that stuck clutch hub. Your welcome.
 
Ussmillerco said:
Very old thread, but as this just happened to me (clutch jammed) after I noticed that 1. my battery wasn’t actually depleting and my ride to work got really a lot harder. Anyway, as one ingenious poster mentioned getting out the hammer and freeing the hub by giving it a whack or 10, so after trying that without success, it got me thinking I could hang my back wheel out the door of my car (bike still attached) and get going fast and drop the back tire onto the pavement, luckily my keen spider sense thought that was a little crazy (at least initally) so I instead decided to take the bike out into the street in front of my house . I then lifted the back wheel off the ground and ran really really fast....well, I’m 55 years old so it was really really fast for me, and once I hit Ussain Bolt speed, I dropped the rear wheel onto pavement, and voila, free hub. Actually to be truthful, I jogged at slightly faster and faster speeds several times until it freed at my near top speed of 12.372 mph. (Or 20.543 kph). My neighbors probably thought what my wife already knows, that I’m a moron , but the bikes fixed. I didn’t even break my hip. Hopefully this helps someone else not to hang their Ebike out the window of their car at terminal speed in an attempt to free that stuck clutch hub. Your welcome.

you said " 1. my battery wasn't actually depleting" is there a number 2 to this story? I hope so :thumb:
 
Good catch.... darn it yeah there should of been a 2. But since I’m riddled with a.d.d., I forget what number 2 was supposed to be....anyway ....look a squirrel
 
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