Motor Wear - When Motor disabled.

[Evolution Stu]

Morning folks,
Now here’s a random question for you.

Upgraded my 2019 Trance E+3 pro to the 2020 E+2 pro in February.
I have Hope Fortus 35 and nice off road tyres but I have removed those for lockdown and am using the Giant AM with some Schwalbe Super Moto-X tyres for the tarmac commute to work and it rolls really well.

indeed it rolls so well that I no longer use assistance on the tarmac and can usually do 25+ miles before I give in to temptation and turn it on.

So, to my question.
as I am now doing 100+ miles a week with the motor turned off, I am questioning the bikes long term reliability.

Does anybody know these Yamaha motors well enough internally, to factually state how much wear and tear they think is being caused to the motor whilst riding it with no power assistance?

I know they use the same motor in the tarmac models so surely it’s suitable for big mileage?
I just wonder if Most of it is wearing out less, without the motor actually engaged?

Pic of her usual home when this is all over... Just for some colour.

 

[simonk]

Don’t really know the answer. Interesting question though. AFAIK the motor never disengages so inevitably there’ll be some wear to the internals.
I agree with you though, they do pedal quite nicely with the motor switched off... there’s no noticeable drag from the motor. Still a heavy bike though!

 

[Tony.OK]

Sounds like you've picked up some sort of virus! Pedalling with a bike not powered up sounds like sickness to me ???

 

[R120]

@Bearing Man might be able to answer you

 

[MattyB]

Other than very slowly wearing the bearings and any internal gearing in the unit (as you would if the motor assist was on, but at a slower rate with the motor off) there shouldn't be any meaningful wear. Brushless motors themselves a very low on moving parts and extremely reliable. It is water ingress to the electronics and bearings that seems to be the motor killer in EMTBs, and that will be the same whether you are pedalling with assistance or not.

 

[Bearing Man]

@Bearing Man might be able to answer you

Interesting question this, I do repair a lot of courier bikes from Deliveroo riders etc. And I have seen damage on Yamaha motors where heavy pedal pressure has eventually stretched or worn the soft aluminium of the right-hand motor case around the bearing, causing the bearing to become loose.
I have also seen this in very high mileage Bosch motors when the bike is used mainly in it's eco mode.

 

[Evolution Stu]

Thanks for the interaction so far guys, much appreciated. ?

I wonder if any of you have some images to share of the motor internals so that we can look at the power transfer route through the driveline and the materials involved?

 

[Evolution Stu]

Pic of her wearing the Tarmac spec wheels and tyres for some colour. Rolls silently. ?

 

[Evolution Stu]

Off road wheels and tyres.

 

[Bearing Man]

Off road wheels and tyres.

Nice shiny bike Stu. Love my Michelins too. Would you like horror pictures of the insides of motors or nice shiny motors?

 

[Zimmerframe]

Would you like horror pictures of the insides of motors or nice shiny motors?

Yuk, what the hell happened to that.

Stus going to be even more confused when he opens his yamaha and finds they have brose internals ??

 

[Evolution Stu]

Nice shiny bike Stu.

She only looks like that now we are locked to tarmac riding here! This was her in the van, the same day I bought her. Lol.

Would you like horror pictures of the insides of motors or nice shiny motors?

Yes please. Would love to see the power flow through the tranny so I can visualise what’s still wearing out whilst the motor is running passively. ???

 

[Evolution Stu]

Yuk, what the hell happened to that.

Stus going to be even more confused when he opens his yamaha and finds they have brose internals ??

Indeed. Are they a Brose motor then?

 

[Bearing Man]

Ok, so here's a Yamaha When you turn the crank without assistance, you just turn the crank, the freewheel mechanism, the large steel drive gear and the gear shaft through the plastic drive gear.
When you peddle unassisted, the large steel gear is locked by the freewheel mechanism to the crankshaft so there is no wear or friction. When the large steel gear turns the gear shaft of the white plastic gear it has a clutch bearing that allows it to freewheel, so again very little wear or friction.
Added a couple of horror pics just to even things up.

 

[Evolution Stu]

Sorry for the delay, I didn’t get an e-mail! Just popped on for a read As I’m off work today and spotted the notification at the top! ?

Thats awesome, thanks for your efforts here.
So generally speaking, me rattling up 400 miles a month “unassisted” won’t be doing any real extra damage to the motor and gears that are related to the power assist side of things?

Fully appreciate that crank wear is crank wear, thats a given.

Do you overhaul these things then pal?
Are you in the uk, and can you give me some idea what you would advise was a good preventative Mileage to take one down and overhaul it? (Or better still, send it to you if your in UK)

 

[Evolution Stu]

As an aside.
when I do ride it unassisted, I have the ride control switched on.
This is purely so the shop can see the genuine rider profile should it go in for any warranty etc as I know the can see miles and battery cycles plus a rider profile showing how many miles in each assist level etc.

 

[Bearing Man]

Do you overhaul these things then pal?
Are you in the uk, and can you give me some idea what you would advise was a good preventative Mileage to take one down and overhaul it? (Or better still, send it to you if your in UK)

Yes, my company Performance Line Bearings, repairs and overhauls most common mid drive motors once out of warranty. We are based in the UK but 80% of our business comes from all over the world.
Yamaha, Impulse and Panasonic all use bronze bush bearings on some of their components, and these really benefit from a clean and re-grease every 2,000 to 3,000 miles. There is also a ratchet and pawl freewheel mechanism that also benefits from a good clean and re-grease.

 

[Zimmerframe]

We are based in the UK but 80% of our business comes from all over the world.

That's good to know ... having a Brose and being in France ...

Can I make a reservation ?

 

[Evolution Stu]

Yes, my company Performance Line Bearings, repairs and overhauls most common mid drive motors once out of warranty. We are based in the UK but 80% of our business comes from all over the world.
Yamaha, Impulse and Panasonic all use bronze bush bearings on some of their components, and these really benefit from a clean and re-grease every 2,000 to 3,000 miles. There is also a ratchet and pawl freewheel mechanism that also benefits from a good clean and re-grease.

Awesome news. Good to know we have a local expert to dig these out of trouble. The warranty thing is a quandary with me.

for most of my working life I have built and maintained race engines for a living, nowadays it’s more calibration of the same, but the point being, maintainance of any rotating machinery is a natural process for me and it’s always in my mind.

It’s hard to leave it alone just because “It’s under warranty” esepcially when I know most of these E-MTB’s do under 500 miles a year and I’ve done that in the last month.

My quandary is...
Do I pull it from time to time and send it you, thus voiding my warranty in the process... or let Giant deal with the aftermath Of not doing so, which inevitably means I get to break down miles from home.

??‍

 

[Bearing Man]

Awesome news. Good to know we have a local expert to dig these out of trouble. The warranty thing is a quandary with me.

for most of my working life I have built and maintained race engines for a living, nowadays it’s more calibration of the same, but the point being, maintainance of any rotating machinery is a natural process for me and it’s always in my mind.

It’s hard to leave it alone just because “It’s under warranty” esepcially when I know most of these E-MTB’s do under 500 miles a year and I’ve done that in the last month.

My quandary is...
Do I pull it from time to time and send it you, thus voiding my warranty in the process... or let Giant deal with the aftermath Of not doing so, which inevitably means I get to break down miles from home.

??‍

This is a most excellent question! If you touch it the warranty is void. If you don't touch it, it could be suffering so that after 2 years, you could be left with a wreck?
The Yamaha manual shows what grease to use, where to put it and what gasket sealant you need, but doesn't tell you when you should do this? The whole thing is a bit of a mess really.

 

[Evolution Stu]

Damn..l was hoping for some very direct inspiration here! ??