STEPS E8000 Motor Service

[S13]

Shell Gadus S2 V100 2 is not designed to assist clutch bearing grip. The fact that we use it for that purpose does not mean it was designed for that purpose.
Shell Gadus S2 V100 2 is designed as a "High performance multipurpose grease". And its application is primarily for bearings (roller bearings, ball bearings etc).

I use it for the metal gears only in my testing. Because it is compatible with metal, and its what i have on hand here in Spain right now (when you are in the middle of nowhere you kinda dont have a lot of options you know...). So i obviously do not recommend other people trying this approach.
However, im not sure if it could do any worse than the Molykote PG75, which started to fail after 500km. Im about 150km in on the Shell Gadus and time will tell which is the better performer.


Now, the OKS270 has PTFE added to it. So while that might be a good grease for the gears, it would obviously be bad for the clutches.
But perhaps we need something with lower friction on those gears to keep temperatures lower. Yes, its too bad we dont know what Shimano uses. So it will be trial and error sadly.

 

[Bearing Man]

Shell Gadus S2 V100 2 is not designed to assist clutch bearing grip. The fact that we use it for that purpose does not mean it was designed for that purpose.
Shell Gadus S2 V100 2 is designed as a "High performance multipurpose grease". And its application is primarily for bearings (roller bearings, ball bearings etc).

I use it for the metal gears only in my testing. Because it is compatible with metal, and its what i have on hand here in Spain right now (when you are in the middle of nowhere you kinda dont have a lot of options you know...). So i obviously do not recommend other people trying this approach.
However, im not sure if it could do any worse than the Molykote PG75, which started to fail after 500km. Im about 150km in on the Shell Gadus and time will tell which is the better performer.


Now, the OKS270 has PTFE added to it. So while that might be a good grease for the gears, it would obviously be bad for the clutches.
But perhaps we need something with lower friction on those gears to keep temperatures lower. Yes, its too bad we dont know what Shimano uses. So it will be trial and error sadly.

Sorry, I was talking in the context of my previous posts with regards the clutch bearing quote. I wish you all the best with your testing.

 

[S13]

Sorry, I was talking in the context of my previous posts with regards the clutch bearing quote. I wish you all the best with your testing.

Thanks!

Sigh... Well, if anything ive became quite skilled in servicing the E8000 with all that trial and error. Its almost a routine job now, just like servicing brakes or suspension.

 

[Strindberg]

Now, the OKS270 has PTFE added to it. So while that might be a good grease for the gears, it would obviously be bad for the clutches.

Thank you for your routine exercises with the STePS E8000, we learn a lot.

Yes, that's right, I didn't tell the OKS advisor about the clutch, which needs to be treated separately.

But it seems that for everything else, gears, ball bearings and roller bearings, this OKS 270 white grease would be good ?

 

[S13]

I would say the OKS 270 is a very promising candidate! Provided you can keep it away from the clutch bearings (and other bearings) of course.
Perhaps ill give it a try once im back home and my Gadus experiment has ended.

 

[Strindberg]

you keep it away from... other bearings of course.

What do you mean with "other bearings" ?

I purchased previously before the complete crash down of my E8000 only sealed ball bearings.
Originally you have in the DU only 2 sealed BB, Shimano cheats wherever he can.

White grease OKS 270 should be good for roller bearings as well.

@S13 Do you noticed a noisy sloshing in your crank, mostly on the right side ?

 

[S13]

I would stick with a generic ball bearing grease for ball and roller bearings. PTFE is great for reducing friction, but you dont want your roller bearings to start sliding. They are supposed to be rolling (with a certain amount of grip of the balls/rollers on the bearing race).

So i'd advice against using the OKS 270 for the roller bearings in the E8000. The sealed ball bearings for the E8000 obviously come pre lubricated so they dont need any greasing (ever).

Besides, generic ball bearing grease is cheap and can be found in any automotive store for a couple of bucks. So why risk it?


Im not sure what you mean by the sloshing sound, but if you mean there is a bit of axial play on the cranks, its normal. Its because of the floating bearing design. Now there shouldnt be any radial play, because that would indicate bearing wear or damage.

(if you'd like me to watch your video's, please post them on youtube so i dont have to download large movie files on my limited 4g data connection).

 

[Strindberg]

@S13 Thank you for your further explanations.

Here my vidéo

 

[S13]

Here my vidéo

Ok, its a bit difficult to see in what direction the crank is moving, but i think the clicking is just from the floating bearing bumping against the side of the case. That would be normal behavior. But it does seem a bit louder than my motor. So perhaps one of those wavy washers has failed like someone posted here earlier, and that allows for excessive axial play?
Im not sure if there is also the radial play based on the video.

By the way, there should be NO difference with the E8000 system switched on or off. Both in the on and off state, the DC motor is unpowered (unless, in the on state, torque to the cranks is provided and the cranks are rotating).
So with the DC motor unpowered there should be no difference whatsoever in the entire driveline.
Im not sure if that is what you are trying to illustrate with the video? Or are you saying that there is a difference between on and off?

 

[joxelitor]

Not sure whats going on here, but numerous times throughout this post I have stated that we do not supply grease for this motor because we never worked out exactly what greases should be used. This motor is not like a Bosch, Yamaha, Impulse etc. and therefore we would not use our greases without long term testing, this was never done on the Shimano because we don't work on Shimano. Using Shell Gadus S2 V100 2, a grease designed to assist a clutch bearing to grip, would be a very bad thing to use on a metal gear! It may even contain ingredients that damage plastic gears!? You can't just call grease by half its name either. Shell Gadus S2 because someone will go and buy V100 3 or V220 2 etc. these are very different greases for very different jobs.

Grease and sealant were the two main issues for me before servicing the DU-8000
I am really surpresied of how some people who has never opened a Shimano motor are writing tutorials and giving advise about this issue.
Please, take catalogs from Loctite, Molykote, SKF and read, there are tons of products for different applications. Grease is a sciense in itself

I can talk only about my limited experience.
Molytote PG-75 has been ok until now after 1200km of riding BUT I have not opened the motor again, mainly because opening, cleaning the gasket surface an applying sealant again is a pain in the ......s. Noise an efficiency seems to be the same.

The only draback observed is a very very slight clutch slip under VERY light pedal force, just standing, absolutely no slip during riding, could be an excess of grease.

I posted in the battery poll thread but here it´s again.
Range increase comparison before and after servicing: 16% gain in range after bearing swap and grease

 

[Bearing Man]

Grease is a science in itself

Finally a voice of reason!

 

[Zimmerframe]

Finally a voice of reason!

I thought it was a 1978 Musical Romantic Comedy with John Travolta and Olivia Newton-John ?

You all seem to be over complicating it for no reason at all

 

[Zimmerframe]

Then again, there was the hit song from the film "You're the one that I want" - which was apparently all about how hard it is to choose the right one .. so who knows ...

 

[pollywaffle]

I've read so much stuff about grease that my head is spinning. I have some Bosch bdu classic grease on hand. Will I damage my unit using this stuff in my e8000? I did scrounge a bit of the existing white grease but not much and some of it is black and unusable.

 

[pollywaffle]

Also, is it normal for the clutch cog to have a little side play?

 

[Strindberg]

Hej Hej friends !

Does anyone know where I could buy a dead E8000?

I would like to learn how to restore such an engine before doing it with mine.

I overhauled myself over 17 engines of my prewar cars...

 

[S13]

I've read so much stuff about grease that my head is spinning. I have some Bosch bdu classic grease on hand. Will I damage my unit using this stuff in my e8000? I did scrounge a bit of the existing white grease but not much and some of it is black and unusable.

The jury is still out on that one.
Reusing the old grease is probably your best bet for now.
From personal testing i can also recommend PG75 for plastic-to-metal gears, and Gadus S2 V100 2 for the clutch bearings (though these results are from short term testing). For the metal-to-metal gears i cannot give any recommendations yet.

And yes, the clutch bearings have side play. In fact because they are similar to roller bearings, there is nothing preventing them from moving side to side (other than a retaining clip for the motor clutch).

 

[S13]

Hej Hej friends !

Does anyone know where I could buy a dead E8000?

I would like to learn how to restore such an engine before doing it with mine.

I overhauled myself over 17 engines of my prewar cars...
....

Cant help you there, sorry.
But as someone who has also done motor and gearbox revisions on 80's cars, i can tell you the E8000 is no rocket science.
If you have the experience you say you have, just go ahead and open your current E8000, should be a pretty easy straight forward job. Just work in a clean environment, ESD safe, and be careful when disconnecting and reconnecting those tiny PCB connectors.

Though i do understand your point of view. I wouldnt mind getting my hands on an old dead E8000 as well...
Just for spare parts, or just to restore it, seems like a fun job!
(my background is actually designing electronics, but i love to tinker with mechanics!)

 

[Strindberg]

Crank play like a metronome.

No difference when the engine is on or off

The noisy swing is rather on the right side,
and even slightly perceptible under the feet when pedaling in a silent forest.

And here my vidéo again.

 

[pollywaffle]

The jury is still out on that one.
Reusing the old grease is probably your best bet for now.
From personal testing i can also recommend PG75 for plastic-to-metal gears, and Gadus S2 V100 2 for the clutch bearings (though these results are from short term testing). For the metal-to-metal gears i cannot give any recommendations yet.

And yes, the clutch bearings have side play. In fact because they are similar to roller bearings, there is nothing preventing them from moving side to side (other than a retaining clip for the motor clutch).

Thanks. Might use the old grease on the plastic gear and bosch on the rest

 

[S13]

Crank play like a metronome.

No difference when the engine is on or off


View attachment 73953


The noisy swing is rather on the right side,
and even slightly perceptible under the feet when pedaling in a silent forest.

And here my vidéo again.

Yeah that would be considered worn bearings.

 

[Strindberg]

Thank you @S13 for your answer.

I can firmly say that there has never been with my E8000
any side play of the crank, even currently with this "noisy" swing.

The E8000 is my third Drive Unit replaced under warranty (!!!... with only macadam and Eco High at 100% of the time),
so I had it fully inspected the first day as a very experienced prewar car owner >>>

I also wonder about this Shimano-official-story of the side play which would be linked to the clutch,
and which would or would not exist with the engine on or off,
because nobody has done the same experience as me ? , or written about this.

This is why I hope that many forumers will do the same experience.

It is easy to improve in this way the crank.

 

[S13]

Ok, so i think ive finally found the true source of the whining sound in my motor. I thought it was the failure of the grease on the metal-metal gears, but i now think that is just a result of the problem, not the cause.
The cause is excessive play on the motor clutch gear (i think someone mentioned it here before, guess it is an important factor to look at!). The rubbing it causes probably heats up the gear and that leads to a failure of the grease. Hopefully the pictures show whats wrong and how i temporarily tried to fix it:

So for now ive added a little bit of clearance by moving one of the bearings to the outside. Also i packed the entire clutch full of grease until it came squirting out all openings. This stabilizes the gear a little bit.
This is my workaround for now, see if this prevents the whining sound and if the grease now holds up for longer than 500kms.

I do think this is a crappy design by Shimano. That clutch gear should never have been fixed with just a tiny retaining clip. It should have had a proper ball or needle bearing. Or otherwise a more precise retaining construction.
Ideally with this construction there should be a very thin shim with a large surface area to provide stabilization for the gear. Perhaps i will try to add one such shim next (if i can find one...)
I think the problem is also compounded by the fact that the gears are helical, meaning there is always a bit of sideways force on the gears. A straight cut gear would reduce this problem. But yeah those make more noise, so i get why shimano went helical here...

Anyway, back to testing next weeks. I'll let you know.
And this means that perhaps the PG75 is just fine to use for the metal gears. That would be good news i guess!

 

[Spiff]

Hi S13, thanks a lot for sharing your findings and the nice pictures. You are becoming a motor expert and we are also learning a lot. I wish Shimano would take into account those comments from the users and improve the motor design and repairability, but...

 

[Strindberg]

Thank you @S13

By following your efficient description, we understand that the DU E8000
is doomed to wear out prematurely because of its "crappy" design, as you wrote.

I don't quite understand the difference you give to this washer and a shim.
A machinist like a turner-miller can easily make me then a larger shim, if it could be one of the solutions, as well.

-----------------------

My third DU, this E8000 engine, which has now 17118 km since the 22st XII 2019
now makes this cyclic noise in the hills like a slight "qven-qven" of an asthmatic duck,
but now also in Eco High and not only in Boost.

I ask me if it still makes sense to replace an E8000 with an E8000,
or if I don't have to implant an EP8.
Of course I will change the connections with the smaller Shimano adapters.

We know that the three big bindings are identical between EP8 and E8000.
But are the overall sizes above them and on the front and rear sides the same?
Indeed, the E8000 already fits with difficulty in the chassis of my Husqvarna.

 

[S13]

So in my last picture, with the term "washer" i actually meant the retaining clip. Its actually a E-clip or E-ring. That clip is too loose, has too much free play. The clip is actually too thin for the groove on the axle. And it doesnt support the gear all the way around (since it has a cut out on one side). So the clutch gear is allowed to wobble too much, because it has no other retaining mechanism (its just free floating).

Its causes an intermittent "ying...ying...ying..." sound as you pedal. Perhaps its identical to what you are describing.
If you were to open up your motor, see if you find the same scratch marks. Then you will know.

So the different solutions that i im going to try are:

1. A thicker E-clip. The standard E-clip measures 0.8mm thick, 9mm hole, 18mm outside diameter. Ive ordered a couple of 1mm thick E-clips, see if they fit. Should arrive by christmas.

2. Put a metal shim between the E-clip and the clutch gear. Still not sure what the best size would be. At most you can get a M12 shim on the axle. The axle itself is M10 however:

Ive ordered several 0.1mm shims with different inner diameters, see if i can make something work.
However, Im hoping the thicker E-clip is sufficient to stabilize the clutch gear... Would be the easiest and cheapest solution.

By the way, im not implying the E8000 is a totally crappy design. In fact most of it is pretty good. Its pretty easy to work on, bearings can be replaced etc and most constructions are pretty solid. But every design has its strengths and weaknesses. And this clutch retaining mechanism is one of the weaknesses for the E8000 motor.

 

[Bearing Man]

Technically the gear should be allowed to float, it will stop it binding or wearing the clip. If all the bearings and wave washers are set right, your noise and damage should disappear. Many of the motors we work on have bearings set at particular depths to give very particular tolerances.

The bearing you pulled back by 0.5mm should have a measurement of 0.8mm from the inner race of the bearing to the end of the gear shaft. The opposite bearing on the other end of the shaft should be 0.4mm.
Each bearing on the other shaft holding the steel gears should both have 0.5mm clearance from inner race to end of shaft.

The wave washers, if flattened, should ideally be changed or at least some form put back into them. This should stop your gears grating without changing any design parameters.

For those reading this who may not be aware... if a bearing needs to be pulled back on a shaft, it should, ideally, be replaced because you will be pulling on the outer race and this can damage the race and balls leading to premature failure.

Hope this helps.

 

[S13]

Thank you bearing man. Next time im in there i will do a measurement of those clearances.

The axles do have a chamfer (is that the right word?) where you press the bearings up to. So it should be obvious how far to press the bearings on (until they cant go any further, i had assumed). Im curious if this deviates from the clearances you mention?

The wave washers, if flattened, should ideally be changed or at least some form put back into them. This should stop your gears grating without changing any design parameters.

If you look at the diagram i drew, you can see that if the wave washers would be too weak or flattened, there would actually be less chance of gears grinding. So i dont see that as a potential cause.

Many of the motors we work on have bearings set at particular depths to give very particular tolerances.

But i could see this as a potential cause, so i will check this next time. Another one to add to the list!

 

[Bearing Man]

Thank you bearing man. Next time im in there i will do a measurement of those clearances.

The axles do have a chamfer (is that the right word?) where you press the bearings up to. So it should be obvious how far to press the bearings on (until they cant go any further, i had assumed). Im curious if this deviates from the clearances you mention?


If you look at the diagram i drew, you can see that if the wave washers would be too weak or flattened, there would actually be less chance of gears grinding. So i dont see that as a potential cause.


But i could see this as a potential cause, so i will check this next time. Another one to add to the list!

The end of the axle is chamfered, I think you mean there is a shoulder on the axle to stop the bearing being pushed on too far, and yes, in most cases you would be right. I am just trying to guess what is causing your gears to rub? I am guessing you did remember the spacer shim that's shown in the photo below?

 

[Strindberg]

Congrats to @S13 and @Bearing Man for further explanations and pix !

Can you give us a picture of the tool to extract the bearings?
And also a link to buy it, please?

(I have a lot of them, but for my prewar cars, and the retailers do not have smaller).