I fixed the Ep8 motor rattle

Longfellow78

Active member
Jan 4, 2022
284
116
Hampshire
When I added xt cranks to my rise i left on the e13 chain ring and rubber boot/ring. The rubber ring touches the inside of the crank and creates slight friction if you backpedal. Without the ring (or with e13 cranks) when you go over rough ground there is a small amount of play as the crank rotates around the axle and is constantly just engaging/disengaging the bite point which is the cause of the noise.

The rubber ring stops this play and eliminates the motor rattle so it is dead silent.
 

volts

Active member
May 15, 2018
331
254
DK
Janky "fix", but if it works it works. Is it silent when you pedal too?
 

Longfellow78

Active member
Jan 4, 2022
284
116
Hampshire
Janky "fix", but if it works it works. Is it silent when you pedal too?
It was unintentional. I just left the rubber ring on and then kept asking why is it that everyone keeps talking about motor rattle when mine is silent. Yes it is silent in all circumstances apart from the whirr of the motor obviously.
 

MAster

New Member
Nov 6, 2022
30
15
Germany
When I added xt cranks to my rise i left on the e13 chain ring and rubber boot/ring. The rubber ring touches the inside of the crank and creates slight friction if you backpedal. Without the ring (or with e13 cranks) when you go over rough ground there is a small amount of play as the crank rotates around the axle and is constantly just engaging/disengaging the bite point which is the cause of the noise.

The rubber ring stops this play and eliminates the motor rattle so it is dead silent.
Sounds awesome 👏
Can you make some fotos on how this is solved? I do not get it entirely from
your description- THx ☺️
 

iJak

Member
Mar 2, 2022
68
26
Vancouver BC
Sounds awesome 👏
Can you make some fotos on how this is solved? I do not get it entirely from
your description- THx ☺️
found some photos here on this thread: Orbea Rise Drive Side Crank Arm Rubber Boot
ironically I dont think mine ever came with the boot.
1669331362429.png
 

gsum

Member
Jul 31, 2021
37
12
Lake District
The rattle seems to afflict some bikes and not others. Our two Orbea Rise bikes haven't had this problem but we do get a good rattling through frequent pedal strikes thanks to the ridiculously low BB height.
 

Jay Bird

Member
Aug 22, 2022
23
11
Mill Valley, CA
When I added xt cranks to my rise i left on the e13 chain ring and rubber boot/ring. The rubber ring touches the inside of the crank and creates slight friction if you backpedal. Without the ring (or with e13 cranks) when you go over rough ground there is a small amount of play as the crank rotates around the axle and is constantly just engaging/disengaging the bite point which is the cause of the noise.

The rubber ring stops this play and eliminates the motor rattle so it is dead silent.
Not so sure this a “fix”? If it is then why does the crank have play and motor rattle when the eThirteen crank is installed with the rubber boot? I know mine did. I replaced my cranks and put shimano on without the rubber boot. Motor still rattles exactly the same, not better not worse. At first I did put the rubber boot on when replacing mine but having it on with the shimano crank caused A LOT of rubbing and drag between the crank rotating and chainring bolt. I really doubt this is how you want it long term. I am sure the motor was designed to have a little play like there is.
 

Longfellow78

Active member
Jan 4, 2022
284
116
Hampshire
Not so sure this a “fix”? If it is then why does the crank have play and motor rattle when the eThirteen crank is installed with the rubber boot? I know mine did. I replaced my cranks and put shimano on without the rubber boot. Motor still rattles exactly the same, not better not worse. At first I did put the rubber boot on when replacing mine but having it on with the shimano crank caused A LOT of rubbing and drag between the crank rotating and chainring bolt. I really doubt this is how you want it long term. I am sure the motor was designed to have a little play like there is.
I'm not sure exactly what you mean about drag - when pedalling the crank and the chainring rotate exactly unison. The only drag created is when you backpedal, whereas normally the crank should rotate freely backwards, with the boot it acts more like a conventional bike and rotates the chain backwards because of this drag. In operation is has no other negative effect as far as I can tell. I might take it off and check. The reason it rattles with the e*13 is because the back of the e13 crank does not touch the boot so there is no friction, with the shimano it rubs, hence the difference.
 

Pacobiker99

Member
Jan 27, 2019
5
4
Madrid
When I added xt cranks to my rise i left on the e13 chain ring and rubber boot/ring. The rubber ring touches the inside of the crank and creates slight friction if you backpedal. Without the ring (or with e13 cranks) when you go over rough ground there is a small amount of play as the crank rotates around the axle and is constantly just engaging/disengaging the bite point which is the cause of the noise.

The rubber ring stops this play and eliminates the motor rattle so it is dead silent.
Could you please tell me where could I buy this rubber ring?
 

Bigtuna00

Active member
Nov 27, 2019
556
336
CA
The rattle that everyone talks about is internal to the motor. It has to do with the gear lash. No external rubber ring is going to resolve it. If you resolved a rattle with that rubber ring, you had a *different* rattle than the "normal" EP8 rattle.
 

gsum

Member
Jul 31, 2021
37
12
Lake District
What's really weird about this is that I found it very difficult to reproduce the rattle until i replaced the original 170mm cranks with shorter 155mm Miranda cranks to reduce pedal strikes. The rattle is now much more obvious and is slightly annoying.
Incidentally, Miranda do not supply the plastic lock which is part of the Shimano crank design,. Nor do they supply the drive side rubber seal. The E13 seal does not work well with the Miranda cranks. Something to bear in mind if you switch to shorter Mirandas because Shimano seem incapable of producing shorter cranks.
 

SwampNut

Well-known member
Oct 26, 2022
272
337
Peoria, AZ USA
Incidentally, Miranda do not supply the plastic lock which is part of the Shimano crank design,. Nor do they supply the drive side rubber seal. The E13 seal does not work well with the Miranda cranks. Something to bear in mind if you switch to shorter Mirandas because Shimano seem incapable of producing shorter cranks.

I have a set of their cranks to install this weekend. So can you tell me more about the parts needed? I haven't disassembled anything yet. Do you have some ideas on what to buy and where? Or how did you solve it?
 

gsum

Member
Jul 31, 2021
37
12
Lake District
I have a set of their cranks to install this weekend. So can you tell me more about the parts needed? I haven't disassembled anything yet. Do you have some ideas on what to buy and where? Or how did you solve it?
The package I received contained just the cranks with pinch bolts and the end caps. That's all that is needed.

For installation of the Miranda cranks, you'll need a 5mm hex for the pinch bolts and a 10mm hex for the pre-load caps. If the crank is aligned correctly it should be easy to push the crank into position on the drive shaft. Install the plastic pre-load cap by hand tightening and nip it up using the 10mm hex to around 5Nm. You could add Loctite to ensure the cap doesn't fall off.

Alternately tighten the pinch bolts to about 15Nm. It's important to check these bolts after a couple of rides and re-tighten if necessary.

Regarding the seal, I've contacted Miranda and they say that their design does not need one.
 

SwampNut

Well-known member
Oct 26, 2022
272
337
Peoria, AZ USA
The package I received contained just the cranks with pinch bolts and the end caps. That's all that is needed.

For installation of the Miranda cranks, you'll need a 5mm hex for the pinch bolts and a 10mm hex for the pre-load caps. If the crank is aligned correctly it should be easy to push the crank into position on the drive shaft. Install the plastic pre-load cap by hand tightening and nip it up using the 10mm hex to around 5Nm. You could add Loctite to ensure the cap doesn't fall off.

Alternately tighten the pinch bolts to about 15Nm. It's important to check these bolts after a couple of rides and re-tighten if necessary.

Regarding the seal, I've contacted Miranda and they say that their design does not need one.

Thanks!!
 

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