Rear Hub Motor - Correct Order for Washers?

[portals]

I'm not really a mechanical guy so here we go...I noticed my rear hub was starting to spin out of dropout on drive side and didn't have a spanner to tighten it back up when I was out.

This is the current setup as it came back from bike guy I just wanted to check the order of where the dropout should go and QA what I got back from shop. I have read that the Axle nut should be on outside on drive side and NOT have a washer on the outside of dropout but I think when I got bike it did have washer on with the flat cutout outside as per the pic, it cannot go in inside as it will block the torque washer and stop it sitting in the dropout?

Can anyone clarify what the order should be to maximise the 'grip' in the drop out?

What is the nut that has a corner cut off it for, is it to stop the washer hitting the silver part on left dropout, is it required?

Is this setup recommended or are there better more secure ways? I guess threadlocker will make zero difference due to the forces involved?

I am working on a 3D Tinkercad design for drive side torque arm that will use the two screws on dropout that the old derailleur guard used to screw on to to stop this happening again. It will be two 1mm thick metal plates.





Also, is this OK for non-drive side? Dropout goes between torque nut (lined up properly) and torque arm?

Thanks

 

[Nealh]

The nut is usually serated /knurled on the inner face this helps to prevent it undoing and aid grip , the washer if a plain one isn't needed outboard of the drop out.
When refitting a wheel always start/work on the LHS first if disc brakes aare used, place any washers so the the calliper/ disc are aligned correctly.
Then one can fit the RHS washers, typically a washer/s may be needed to ensure freewheel or cassette doen't rub on the inside of the dropout.

 

[Nealh]

Can't say about the flat edge washer, not come across on before.
One would think if any where it would go inboard of the ARW .

 

[chris_n]

The flat has been put on the washer that is outboard of the dropout in order to clear the tab of the anti rotation washer because the tab is too big, IMHO.

 

[saneagle]

The flat has been put on the washer that is outboard of the dropout in order to clear the tab of the anti rotation washer because the tab is too big, IMHO.

On most bikes, the washer prevents the wheel from being removed because it can't slide past the derailleur fixing point, in which case you have to remove the nut and washer completely from the axle before you can slide the wheel out, which is a nuicance. Grinding a flat on the washer would solve that. In all the installations I've seen and done, I can't remember ever seeing a drop-out thin enough to let the anti-rotation washer tab poke right through.

For OP, there is no rule about how washers and spacers should be fitted. You arrange them in a way that works to get:
1. The correct alignment of the disc to the caliper if you have a disc brake.
2. The correct clearance between the cassette and the frame so that the chain doesn't rub.
3. The rim central to the frame between the drop-outs.

 

[chris_n]

On most bikes, the washer prevents the wheel from being removed because it can't slide past the derailleur fixing point, in which case you have to remove the nut and washer completely from the axle before you can slide the wheel out, which is a nuicance. Grinding a flat on the washer would solve that. In all the installations I've seen and done, I can't remember ever seeing a drop-out thin enough to let the anti-rotation washer tab poke right through.

If that is the case then there is no point in it being there, as @Nealh says the nut should be serrated aiding grip and removing the need for overtightening to keep the wheel secure.

 

[saneagle]

If that is the case then there is no point in it being there, as @Nealh says the nut should be serrated aiding grip and removing the need for overtightening to keep the wheel secure.

I can't say definitely all, but it's at least most of the commercial installations have a washer under the nut. I can't say which would be best between the nut with and without the washer. I can see merit on both sides.

 

[Nealh]

Some of the washers that I have are also like the inside of the nut , in that they are also serated on both sides .
Each fitment and order of washers, tabe washers will differ but I see little point in having a plain washer if the nut is serated.

 

[MikelBikel]

Is there any merit in getting those deluxe nuts with the captive serrated washer, for grip and minimise dropout scratching?
Posh bikes seemed to have them!
Not sure where they're measuring the 14mm on these, across the flats?

 

[saneagle]

Is there any merit in getting those deluxe nuts with the captive serrated washer, for grip and minimise dropout scratching?
Posh bikes seemed to have them!
Not sure where they're measuring the 14mm on these, across the flats?
View attachment 60232

M14 is the axle thread. Nearly all geared hub-motors have M12 threads.

In spite of that, if you find the listing for the correct M12 set, they should be the same as what you already have except you should might have the other type of anti-rotation washers.

 

[Nealh]

Is there any merit in getting those deluxe nuts with the captive serrated washer, for grip and minimise dropout scratching?
Posh bikes seemed to have them!
Not sure where they're measuring the 14mm on these, across the flats?
View attachment 60232

thye are 14mm x 12mm , 12 is across the flats.
To big for std geared hubs, one needs 12 x10 for geared hubs.

 

[portals]

Thanks for the responses.

The axle nuts do have the serrated inside edges for grip however the washer on drive side next to axle nut doesn't, just a plain washer, I have seen some one-sided serrated washers in that position and will look to see if I have any.

Is there any advantage to adding a second axle nut to each end of the axle if I have the space to add additional 'clamp'?

Currently trying to get the bleedin torque arm of the axle for 20min, it should just slide off but is stick fast, have just sprayed some WD40 in and plan to start smacking it with a mallet soon...

 

[chris_n]

Having actually looked at your pictures I see that the Allen screw that is holding the derailleur hanger on is a major concern. There is no way you are going to get your axle fully into the dropout with that in the way. It needs countersinking and a countersink screw that sits below the level of the hanger before you do anything else.

 

[saneagle]

Having actually looked at your pictures I see that the Allen screw that is holding the derailleur hanger on is a major concern. There is no way you are going to get your axle fully into the dropout with that in the way. It needs countersinking and a countersink screw that sits below the level of the hanger before you do anything else.

I can make sense of it now. The flat on the washer is to clear the screw that holds the derailleur on. It's difficult to see from the photo because of the angle. One from the side would have been better. It looks like the flat on the washer doesn't go far enough and when the axle is far enough in, the flange on the nut is going to catch on the screw, so a normal plain hex nut might be better.

Is that a direct drive motor? If so, the axle is 14 x 10mm.

 

[chris_n]

I can make sense of it now. The flat on the washer is to clear the screw that holds the derailleur on. It's difficult to see from the photo because of the angle. One from the side would have been better. It looks like the flat on the washer doesn't go far enough and when the axle is far enough in, the flange on the nut is going to catch on the screw, so a normal plain hex nut might be better.

Is that a direct drive motor? If so, the axle is 14 x 10mm.

That still is no reason for that washer to be there on the outside. It may be why it was put there but it isn't the correct answer to ensuring the axle is fully home in the dropout and secure. Looking at the state of the dropout there is no way it is ever going to be secure, the slot in the dropout is wider than the slot in the hanger. The whole thing looks like a bodge to me, even the washer that is under the hanger screw appears to have been pushed right back to try and gain clearance instead of replacing it with a countersink screw.

 

[portals]

Having actually looked at your pictures I see that the Allen screw that is holding the derailleur hanger on is a major concern. There is no way you are going to get your axle fully into the dropout with that in the way. It needs countersinking and a countersink screw that sits below the level of the hanger before you do anything else.

Yes, the Allen screw that is holding the derailleur hanger takes up some space in dropout but the bike has always been like that even with original derailleur from Halfords (it's an old Apollo), that I removed.

I don't think there is another way to mount derailleur on the frame given it's design?

What do you mean by 'countersinking and a countersink screw', could you explain a little more or post some pics that show what you mean? Is there is another way to mount derailleur to give whole dropout available to axle?



I found a photo from original build so yes that shows what the cut washer was used for:

 

[portals]

That still is no reason for that washer to be there on the outside. It may be why it was put there but it isn't the correct answer to ensuring the axle is fully home in the dropout and secure. Looking at the state of the dropout there is no way it is ever going to be secure, the slot in the dropout is wider than the slot in the hanger. The whole thing looks like a bodge to me, even the washer that is under the hanger screw appears to have been pushed right back to try and gain clearance instead of replacing it with a countersink screw.

Rear wheel was secure for a good few months before I had to get bearings and cassette replaced and bike guy didn't torque up enough, partly my fault for not doing usual check and also marking nuts with sharpie straight line to monitor torque.

Dropout slop not as bad as it looks partly due to camera angle, the allen nut isn't tight so it's slipped a little.

A custom 3D printed torque arm will be going on to drive side (cannot find any arm on market that will fit on drive side), and other side upgraded to a 5mm hammer torque arm.

If there is a smarter way of setting up the bike I'm all ears/eyes etc., but not yet ready to bin this frame after time and effort put in so far.

 

[portals]

This is what the bikes looks like btw, found these pics eventually...cannot see any other way to configure derailleur.

 

[Sturmey]

..cannot see any other way to configure derailleur.

Its not that clear from your post whether your axle is 12 X 10 or 14 X 12. Anyhow I once fitted a Bafang geared hub with 12 X 10 axle to a similar 'semi horizontal' dropout type Apollo hybrid bike.
I removed the derailleur from the dropout and pushed the motor fitted with the anti rotation washers right back to the rear end of the dropout. I modified the derailleur hanger by discarding the screw fitting and semicircular nut thingy that normally takes up room in the dropout. I also ground flat the indent/rise that on the inside of the hanger and deepened the hanger slot.
The derailleur than is just held with its deepened slot in the axle and pinched between the bike frame and the nut. It wont turn. A washer between the nut and derailleur is desirable. You need to keep the derailleur hanger pushed home as you tighten the nut.
This works well but there is one drawback and that is that you have to be careful when you remove the wheel not to get the chain in a knot as the derailleur has nothing to support it (tends to turn from the springs) when the wheel is removed.

 

[chris_n]

^ This is exactly what you need to do.^