Rocky Mountain PowerPlay motor replacement

Flatslide

E*POWAH Master
Jul 14, 2019
265
250
Dunedin NZ
With the Dyname drive being so quiet, I didn't think to inspect the primary drive (I've not found or received info from RM about inspecting or servicing the primary drive).
After another member discovered his was badly worn, I checked mine to see and discovered the chain was worn and the motor drive pinion has bent teeth.
I replaced the #25 chain and it's 2 o-rings, but the bent teeth clip the new chain so it's noisy - still works fine. I asked the dealer about purchasing a new pinion, but apparently the motor has to replaced... This is being performed under warranty next week. The bike has travelled 8000 km and the motor runs perfectly so although I'm receiving a new unit, I am a bit concerned about not being able to replace a crucial part going forward beyond the warranty period. I'll be asking that question when I drop it in for sure.
20201130_183807.jpg
 
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Flatslide

E*POWAH Master
Jul 14, 2019
265
250
Dunedin NZ
The pinion was not designed to be replaced ?
That's how they're playing it, but while it's under warranty I ain't gonna remove the motor end cover to see inside lol. I will enquire when I drop it off Monday, but I don't think the shop really knows. I would expect the part is replaceable, but it's odd to me (and a little wasteful), to be replacing a sweet motor instead of the worn part.
 

nineT

Member
Apr 16, 2020
32
14
Bavaria
Bought this week a #25 chain and checked the length. Checked my 5430km chain against the new one. 0,3 mm longer across 23 chain links.
In other words ~ 0,2 %. Unfortunately the motor cog looks quite worn, but still no noise or any other shortcomings.
I wonder how a new cog looks like...

cog 5430km.jpg
 
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nineT

Member
Apr 16, 2020
32
14
Bavaria
Interesting: the transfer chain replacement video
That motor used for this tutorial looked brandnew. Still the motor cog looks like this:
cog replacement video.jpg
 

Flatslide

E*POWAH Master
Jul 14, 2019
265
250
Dunedin NZ
Interesting: the transfer chain replacement video
That motor used for this tutorial looked brandnew. Still the motor cog looks like this:
View attachment 50843
Hahaha, indeed. Could be that's how it is supposed to be. Doesn't seem correct though when one considers every other roller chain/sprocket set up. Maybe it's some new Canadian secret black magic technical innovation spooky engineering. I'll open up my new one and check when I get a chance.
 

nineT

Member
Apr 16, 2020
32
14
Bavaria
Right. Even if the cog is very endurant, it will be worn some day. It must be serviceable without changing the motor or any other action that cannot be done in a reasonable equipped workshop. With all my consideration for the very nice performance, this is very bad. Would not have bought this bike if I knew this.
I can only hope to be wrong.
 

Flatslide

E*POWAH Master
Jul 14, 2019
265
250
Dunedin NZ
So the good news is the cog looks that way from new. This confirms my suspicions about Canadian black magic :LOL:
I sent photos etc to the shop and was provided a replacement unit so who knows? I remember comments about a firmware upgrade last year that my 2019 bike didn't have. This new unit and controller feels like it gives more support over a wider cadence to the original. Could all be in my head though, just seemed to be rocking up the hill today with fewer shifts.
 

Flatslide

E*POWAH Master
Jul 14, 2019
265
250
Dunedin NZ
I'm sure it must be a serviceable part. With all that torque though, it needs to be secured in a way that it will never work loose - just look at the damage the transfer cog can do to the transfer shaft spline if left to rattle around like happened to that other poor bugger on here. I feel a bit silly tbh now knowing that the pinion drive wasn't actually damaged, but in my defence, I did supply photos and originally enquired about purchasing the part. I wonder now how often to replace that chain going forwards.
 

Dan63

Well-known member
Feb 4, 2019
289
170
Brisbane
If you have the 2021 firmware loaded you will now have much better motor support over a widen cadence range :)
 

nineT

Member
Apr 16, 2020
32
14
Bavaria
It is a trick of the camera. I was a bit scared when this posting was issued and looked from different perspectives. The "bent teeth" changed position when I was moving my perspective. That weird tooth profile is causing this effect. Looks like a Shimano 11t that was mounted the wrong way...
But: the wear of the #25 chain was alomost neglectable, my confidence was largely restored.
If (!) the normal replacement criteria of 3% chain elongation applies, I will theoretically need the next chain at 80000km (?!).
Probably this is wrong, as I grow older the ECO Mode will be used less.
Of course I will also not risk damaging the cog and replace sooner. But even at 1% this means 25000km, if the wear keeps at this pace.
Still I cannot see the cog on any spare parts list, and I dislike the idea of shipping the bike for service reasons :mad:. Even if this is in quite a distant future. Not having dozens of plastic gears and lots of bearings less than other brands did attact my attention to RM....

Maybe I am a bit spoiled, having used one (second hand) Speedhub drive on 3 bikes for 12 years, this means at ~50000km. Sadly it is very difficult to fit it to the Altitude, so I just bought the third shifting chain.
 
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