PEEK Gear for the Ultra Needed

brake034

Member
Region
Asia
I think the best and quickest way to get a few test samples in solid PEEK 30% carbon is to send a gear set to the guys I am in contact with, let them reverse engineer it and have them send us the samples to test for breakages. If they work to reduce noise but tend to break, we might redesign with a steel core.

There are basically 2 ways I can send them the gear set; 1) I can order a set from China and ship it right to my supplier. Or 2) I get the gear set out of my brand new G510 motor and send it to them, problem is that I can access that motor only end of April. A third option could be someone to send me the gear set so I can pass it on.

Following option 1) I will check today if the set is in stock, if so I will order it and have it shipped directly to the supplier. This is the fastest route with shortest logistic lines and probably the cheapest way to kick it off. Will follow up later today.

As a side note, the supplier of the gear set has other G510 motor components available like pawl clutches and steel primary gear.
Should we have an emergency stock of these components for rapid shipping? I know these components are not always readily available and the costs aren't too bad either.
 

Merle Nelson

Well-Known Member
Region
USA
Prototypes don't need a Computer Controlled machine. One or a few can be made on standard machines.


CNC comes in if it proves out and you want 100 copies of the same thing. (As I understand it.)

Edit: Oops, sorry didn't know this was just covered in another way when I posted.
 

Ebiker33

Well-Known Member
Actually there might be a way to bring the cost down, just have one gear as PEEK look at this video of the original, it's just one gear.
And it's the smaller one of the two we have been talking about, again further reduction of cost.
I have posted a thread in the general forums asking for input on anybody who ever owned a nylon geared ultra, for input.

 
Last edited:

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Another potential customer here!
 

Bubba zanetti

Active Member
Region
Canada
City
Trail, BC
This is a great thread and worthwhile project. Not trying to hijack, but I have tried unsuccessfully to source a gasket for this motor. I wanted to inspect the quality and amount of grease. Luna, California Ebike and WattWagons have zero in stock and nothing online. It seems others on several forums have had the same result. Quite the disincentive for some DIY maintenance/upgrades or performance tweaking. Anyone have thoughts or a source?

And yes I would happily contribute some $ to this project.
 

Merle Nelson

Well-Known Member
Region
USA
Old time chainsaw users, loggers, would make their own gaskets with a workable material (often beer can aluminum or cigarette carton) and a ball peen hammer.
 

Ebiker33

Well-Known Member
This is a great thread and worthwhile project. Not trying to hijack, but I have tried unsuccessfully to source a gasket for this motor. I wanted to inspect the quality and amount of grease. Luna, California Ebike and WattWagons have zero in stock and nothing online. It seems others on several forums have had the same result. Quite the disincentive for some DIY maintenance/upgrades or performance tweaking. Anyone have thoughts or a source?

And yes I would happily contribute some $ to this project.
I am not sure if Pushkar is opening every motor and installing the X1 controller, if so, and he ruined a gasket that would be an issue.
But you bring up a related point, even if we are able to get the gear, gaskets may need to be replaced as people open and close up their motors and to put the gear in, thanks for bringing this point out.
That is why when you do something brand new the old brainstorming of many minds covers all the angles.
 

Bubba zanetti

Active Member
Region
Canada
City
Trail, BC
Old time chainsaw users, loggers, would make their own gaskets with a workable material (often beer can aluminum or cigarette carton) and a ball peen hammer.
Yes. It’s crossed my mind. I just find it confounding why I can’t buy a gasket to have on hand should I need it. And it appears that problem is specific to the Ultra.
 
Last edited:

brake034

Member
Region
Asia
What is key to me in the video is that it's been said that there is zero difference in sound between the old nylon/teflon gear and the new steel one?

Sourcing the gaskets will be relatively easy, we just need a sample for size and material choice.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
What is key to me in the video is that it's been said that there is zero difference in sound between the old nylon/teflon gear and the new steel one?

Sourcing the gaskets will be relatively easy, we just need a sample for size and material choice.
That, my friend, is simply not true. If that were actually the case, I doubt you'd have the support seen here for a composite gear of some sort. -Al
 

Ebiker33

Well-Known Member
What is key to me in the video is that it's been said that there is zero difference in sound between the old nylon/teflon gear and the new steel one?

Sourcing the gaskets will be relatively easy, we just need a sample for size and material choice.
Somehow I missed that statement, now I think we need the whole things in PEEK so 2 gears that are meshing have PEEK to steel, and after watching it again it was the larger gear that was nylon.
It seems that entire part is the replacement anyways, I don't think we want to start tearing off bearings and all that, just make the entire replacement part like Bafang makes it. Only with 2 PEEK gears.
I also noticed he broke the gasket on second watch when he opened the motor up further making Bubba Z point.
 
Last edited:

Cuz Vinny

Well-Known Member
Overkill and unnecessary expense. I’d rather have a little noise than compromise durability. Plus I like my 2300 watts.
 

Ebiker33

Well-Known Member
Overkill and unnecessary expense. I’d rather have a little noise than compromise durability. Plus I like my 2300 watts.
I wouldn't mind 1600 watts peak to cut back on some noise, that's where testing is needed.
Get the best of both worlds, power and less noise.
If this project rolls out, I would like lots of testing done, we need to know how far you can push it.
Pushkar is good at testing new components at all kinds of different wattages, in fact he can start at 750W, and if it keeps surviving he can keep moving it up, even use an X1 lab motor at 3000W and if it survives that then it will survive in any stock Ebike regardless.
 

brake034

Member
Region
Asia
I will have the steel gear set shipped out today, will arrive in 2 days at the PEEK supplier so their engineers can look at it.

I will finance the steel gear plus shipment out of pocket but we will need a model to finance the making of prototypes....

I am working on the gaskets too.
 
Last edited:

brake034

Member
Region
Asia
As a project baseline, I think we need to establish sound levels with the current steel gears first. Based on that dataset we could than see how much PEEK reduces noise.
I don't have any ultra motors mounted at the moment, nor do I have a sound meter, although these seem quite cheap?
 

pushkar

Well-Known Member
So I spoke with a couple of you guys here 1-1. Thanks @brake034.

I wanted to follow with a slightly deeper background based on some testing we did a few months ago (and continue to do). Please note that these issues apply to all motors - not just Bafang.

1. The way the gears sit in a mid drive e-bike motor (typically) is based on the motor casing and positioning of the stator / core etc.
2. The tolerance for these motor casings is low. Across different production batches, you may see ±0.25-0.5mm change. That is significant.
3. All machined gears are also made with loose tolerance - sometimes deviation is as high ±0.1-0.3mm

Note: For this discussion I am ignoring the thermal sink issues (motor heating , lack of effective cooling).

With loose tolerance, riders will notice the following
1. Louder noises - as gears rotate, the higher the effective gap, the louder the noise. I have tried Bafang and bosch Gen 4- both motors have the "noise".
2. As you ramp up to higher speeds (and higher RPM), because the Ultra is all steel internally, there is a rapid increase in temp due to these tolerance issues. The motor doesnt get too hot because it has a fairly large heat sink. This heat issue is present in Bosch though- if you go turbo, thermals are comparable to the bafang m600 - too much power in a smaller enclosure.
3. If we put 30 amps through bosch / yamaha / etc, the gears will absolutely start to fail (IIRC most are actually nylon!)

With that background, a Single PEEK gear for the bafang ultra IMO is not a sufficient solution. It may work for lower power motors (say 300-500W nominal) , but with higher wattage, high manufacturing tolerances, we should absolutely expect a higher failure rate with PEEK.

So why are the motors made with loose tolerances?
1. Cost. tightening the tolerance adds (anecdotally) 25-50% increase in production cost.
2. Manufactuers may also need to re-do molds and tooling. It is a one time cost but significant enough investment upfront.

Which are the quiet motors then ?
1. Brose and Yamaha motors appear to have better tolerances than Bosch, Shimano, Bafang (Anecdotally).
2. Lower wattage will allow any manufacturer to do all PEEK without addressing the tolerance issues.

The ideal way to tackle noise / weight / heat is to take a holistic approach
1. Better tolerances on casing.
2. Better tolerances on gears.
3. PEEK for ALL gears, not just the primary gear.

This allows for reduced noise, better gear inter-locking, and noticeable reduction in heat generation. This may not be the answer everyone is looking for, and we may have short term success with a single PEEK gear . However it is not an effective long term /scalable solution. The problem is much deeper, and it is not limited to Bafang. All ebike motors have (in general) high tolerances, most just don't run into it because they have lower power motors.


If we want to look at mid-drives with nice motors, look at the new Zero motors drive train - IIRC, they actually reduced the motor shell size by a little in the new versions, as their quality has improved. Also, TDCM (the hub motors on stromer) - the higher end versions - very very tight tolerances. OOh.. my fav is Pinion gear box. I know its a gear box- but it is beautiful. It helps to have a fluid bath :)
 

onlineaddy

Well-Known Member
Region
USA
City
San Diego
I’m in love with the Pinion as well.

Gotta look up the Zero motors. That I’m not familiar with.
 

onlineaddy

Well-Known Member
Region
USA
City
San Diego
Zero is the motorcycle company. They are now also makign the drive trains for Polaris and Harley bikes i believe.
Oh, that Zero! So you're talking about e-motorcycle motors, not e-bike motors then (at least not yet 🤔).