EP8 - reduce the noise rattling noises from the motor

Aug 17, 2020
7
9
portugal
Is there any way to reduce shimano EP8 rattling noises while going downhill?

What is the cause for the noise and ways to technically reduce or eliminate it?

After waiting for so many time for the bikes with it is quite disappointing to have this noises.
 
Apr 18, 2020
117
33
germany
It's a freehub inside the motor that has slight play and the chain moving creates the noise. Eliminating it is not easy if not impossible without changing the overall design. It is less noticeable with the old motor so it probably also has something to do with the motor being smaller.
 

Gary

Old Tartan Bollocks
Author
Subscriber
Mar 29, 2018
10,496
10,688
the internet
most of them can't even drive a car in a straight line ! ;) :ROFLMAO:
"Se détendre"

93675_giphy-downsized-large.gif


:sneaky:
 

sdcoffeeroaster

Active member
Jul 22, 2018
551
204
San Diego, CA
My old motor on my Jam2 just started to make a similar sound under light or not load. It's a rattling, clacking sound that goes away under medium to heavy loads. I have 3800 miles on the motor now and not sure where to go with this. Seems like excessive backlash of some sort. Checked freewheel, chain, cassette, clutch, pedals, etc. but I fear it's the motor and while it's 1 1/2 yrs old I doubt I can find a dealer to warranty it since the Focus dealers are selling other brands now and not Focus.
 

sdcoffeeroaster

Active member
Jul 22, 2018
551
204
San Diego, CA
Yes there is an ex-Focus dealer I'll try first of course. They do need to be familiar with Shimano ebike motors to know it's not normal. I plan to ride it some more because it does seem to be getting worse. The Focus dealer I bought it from is up in San Dimas, 125 miles away. So far I can't find any other source of this noise and it's perfectly quiet when climbing or just bouncing the bike around when not pedaling. One day it was very quiet and at the end of my ride two days ago I noticed this. I imagine it is very similar to the noise the newer motor makes or worse.
 

sdcoffeeroaster

Active member
Jul 22, 2018
551
204
San Diego, CA
Have you actually ridden an EP8 powered bike?
No but I've heard about the noise they make under no load. Turns out I finally was able to rule out the motor. I put my Raceface Novatec wheel on and the noise went away. While the freehub looks OK in the old Exile speedtuned cf wheel, I think there might be a bad outboard bearing. It's not exactly rough or even loose but there is a slight tightness when snugging the drive shafts in one or more of the bearings and maybe some slight roughness. And the cassette and/or chain could be suspect now too. I'm replacing all the hub bearings and installing a new freehub assy soon along with a new chain and cassette so maybe I'll be able to identify the source of the noise. The 4 pawls look perfect along with their springs. The Novatec hub I'm using has the 462 5 cartridge bearing steel freehub so it's pretty tough but heavy too.
 

NZSpokes

New Member
Sep 29, 2020
47
26
Auckland, New Zealand
No but I've heard about the noise they make under no load. Turns out I finally was able to rule out the motor. I put my Raceface Novatec wheel on and the noise went away. While the freehub looks OK in the old Exile speedtuned cf wheel, I think there might be a bad outboard bearing. It's not exactly rough or even loose but there is a slight tightness when snugging the drive shafts in one or more of the bearings and maybe some slight roughness. And the cassette and/or chain could be suspect now too. I'm replacing all the hub bearings and installing a new freehub assy soon along with a new chain and cassette so maybe I'll be able to identify the source of the noise. The 4 pawls look perfect along with their springs. The Novatec hub I'm using has the 462 5 cartridge bearing steel freehub so it's pretty tough but heavy too.

I have an EP8 bike. Its there but not that bad. Sounds like an old mech. Im going to fit a 52t ratchet to my DT hub. I dont expect to hear ot after that.
 

sdcoffeeroaster

Active member
Jul 22, 2018
551
204
San Diego, CA
I have an EP8 bike. Its there but not that bad. Sounds like an old mech. Im going to fit a 52t ratchet to my DT hub. I dont expect to hear ot after that.
Yeah I'm rebuilding my hub with all new bearings because another wheel made the noise vanish. It must be a bad bearing and I have a new freehub assy too. This is not the EP8 which has a noise of it's own.
 
Aug 17, 2020
7
9
portugal
I have an EP8 bike. Its there but not that bad. Sounds like an old mech. Im going to fit a 52t ratchet to my DT hub. I dont expect to hear ot after that.
Don’t understand how the hub impacto on the motor noise. Is that something that actually works or just a test?
 

melmark

Active member
Dec 29, 2018
189
105
US
There is no fix for this at the moment. I heard Shimano may be working on this for future revisions. The brand of bike may make a difference as well with carbon vs aluminum frames etc. Doesnt bother one bit on my Commencal
 

Vertas

Member
Mar 22, 2020
42
33
Denmark
After riding my Bullit for 60+km now in various terrain, I must say this rattle noise has been blown up, it's the smallest of noises and I rarely even think of it. If no one told me, I'd hardly ever notice it tbh.
 

Vinnykiwi

Member
Oct 19, 2020
16
3
AUSTRIA ??
Has anyone directly compared the rattle (Using similar frame material) between the EP8 and Bosch Gen4? The Gen4 rattle is IMO very noticeable...at least in a carbon frame.
 

Vertas

Member
Mar 22, 2020
42
33
Denmark
One thing about the rattle tho, if you record a ride with a GoPro or something, then you can really hear it ? But I can live with that ^^
 

Beekeeper

🍯Honey Monster🍯
Aug 6, 2019
1,745
2,194
Surrey hills
Fill the entire motor case with honey ?
No more rattles

You will also get the sensation of pedalling through treacle at all speeds not just above cut off.
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

522K
Messages
25,789
Members
Join Our Community

Latest articles


Top