Syncdrive sport motor stripped gear

[funnel]

Yesterday on a ride when going over a big rock uphill the motor suddely started making a strange noise. Luckily was close to home and could drive without the motor assistance home.

Today I opened the motor to check what's going on and I see the stripped nylon gear. I was expecting it due the noises it made.

After googling it's apparanetly a common occurence Yamaha PW-X and PW-X2 nylon gearwheel repair

I also found an online shop that has the Yamaha version that looks like the same part Yamaha PW, PW-SE Plastic Drive Gear Assembly - eBike Motor Centre (Performance Line Bearings)

EDIT: The right Yamaha part for the Syncdrive Sport is named PW-ST POM if anyone from the future is interested and doesn't want to order the wrong part like I did. Basically it's a combination of the axle from PW-SE and the plastic gear from PW-X2. Ask the seller and check the dimesions of the plastic gear since there're two variants, and three variants of the axle(and the top smaller gear).
I got it from this shop eBike-Doktor eBike-Motor Ersatzteile + Motorkomponenten für BOSCH, BROSE, YAMAHA , etc. . Recommended seller. Very professional.

Will order the part and fix it. Hopefully doesn't happen again.

 

[TheLob]

Thanks for the photos and info,

 

[ilostmypassword]

Yikes. If you don't mind me asking what weight are you? Is it related to this?

 

[funnel]

Yikes. If you don't mind me asking what weight are you? Is it related to this?

I have 89kg. I have a theory of what caused it. I'm thinking the motor doesn't have enough torque to cause this, but possible has a lot of holding power. And if you tried to rotate the wheel backwards when the motor is on full power you could theoretcally strip the gear.

It's possible since this was the first time I tried to go over a bigger rock when going uphill and I got stopped instantantly in the middle of it and I basically did a small jump backwards and all of the force of my weight+bike including the falling backwards went directly into the motor gear. I also have new tyres that have a perfect grip so that helped too.

I did about 15000 km in 2 years on all sorts of terrain and I think it's hard to cause this if you drive in a normal way.

 

[ilostmypassword]

I have 89kg. I have a theory of what caused it. I'm thinking the motor doesn't have enough torque to cause this, but possible has a lot of holding power. And if you tried to rotate the wheel backwards when the motor is on full power you could theoretcally strip the gear.

It's possible since this was the first time I tried to go over a bigger rock when going uphill and I got stopped instantantly in the middle of it and I basically did a small jump backwards and all of the force of my weight+bike including the falling backwards went directly into the motor gear. I also have new tyres that have a perfect grip so that helped too.

I did about 15000 km in 2 years on all sorts of terrain and I think it's hard to cause this if you drive in a normal way.

Interesting thoughts on how it happened. Technical stuff does often have a bit of back pedalling as you balance etc. You would have thought is would; not be as catastrophic as that.

 

[funnel]

Found another post where the same thing happened to another guy. He says it was a pedal strike. Maybe it was a pedal strike for me too. All happened so fast.

Yamaha PW-X - Giant Trance e+ 2019 - Stripped Flywheel - Motor Replacement

This is the result of a pedal strike - $1,800 AUD - Thankfully covered by insurance. I have found the COG for $700 Pounds - But didn't appear to be readily available. Thinking of using a 3D printer Any thoughts out there

www.emtbforums.com

 

[Rickster]

Funnel what’s the current status on your motor, did you fix it yet ?

 

[funnel]

Funnel what’s the current status on your motor, did you fix it yet ?

I have troubles sourcing the spare part to Europe. The UK shop suggested a shop in Germany that is closed this week, so I'm waiting. I didn't think it would be that hard to get a stupid gear.

I'm literally thinking of trying to design it in solidworks and try to 3D print it. But I doubt it would be strong enough. I would rather just by it if somebody wanted my money but nobody really seems to care, not Yamaha, and not Giant.

I'm disapointed buy the local and global service chain. I think they should be having this part in stock in every Giant/Yamaha ebike service center, but they don't. Apparently Giant only replaces the entire motor and send the broken one back to the factory.

 

[Rickster]

I feel your all to familiar pain , but your idea has already been done and readily available. Check this out..https://www.tindie.com/products/avandalen/yamaha-pw-x-and-pw-x2-nylon-gearwheel-repair/

I actually have one sitting in a box I could sell you but it might be faster to order direct. Let me know how I can help.

 

[funnel]

Yeah. I already asked the seller and he replied they're not the same. I need the one for the PW-SE version, not the X, X2. Maybe they're a different diameter? Can you measure the outer diameter?

 

[Rickster]

Rats, sorry man.
Btw do you have the actual Yamaha part number ?

 

[amadorjimenez]

Yesterday on a ride when going over a big rock uphill the motor suddely started making a strange noise. Luckily was close to home and could drive without the motor assistance home.

Today I opened the motor to check what's going on and I see the stripped nylon gear. I was expecting it due the noises it made.

After googling it's apparanetly a common occurence Yamaha PW-X and PW-X2 nylon gearwheel repair

I also found an online shop that has the Yamaha version that looks like the same part Yamaha PW, PW-SE Plastic Drive Gear Assembly - eBike Motor Centre (Performance Line Bearings)

Will order the part and fix it. Hopefully doesn't happen again.

View attachment 86115

View attachment 86116

Hello, I believe this same thing happened to me last weekend. I just have one question, did you whole system turned off and doesnt back on again? after this motor noise or bad pedal my bike doesnt turn on at all. Did this also happen to you too? I am trying to rule out reasons. Thanks beforehand!

 

[funnel]

Hello, I believe this same thing happened to me last weekend. I just have one question, did you whole system turned off and doesnt back on again? after this motor noise or bad pedal my bike doesnt turn on at all. Did this also happen to you too? I am trying to rule out reasons. Thanks beforehand!

No. Mine worked fine even with the broken gear. It was just making noise when the small gear went over the damaged part of the bigger broken gear.

 

[funnel]

Finally repaired it today after a month!

The right Yamaha part for the Syncdrive Sport is named PW-ST POM if anyone is interested and doesn't want to order the wrong part like I did. Basically it's a combination of the axle from PW-SE and the plastic gear from PW-X2. Ask the seller and check the dimesions of the plastic gear since there're two variants, an three variants of the axle(and the top smaller gear).