Mik, question about gear noise

I would contact Vectrix first, maybe they have seen the light and take gear box noise more serious by now.

If not, then you might need to ask them if you can have it fixed or improved by someone else without voiding your warranty. Here is a relevant discussion about this on V.

In my case Vectrix Australia (possibly after discussion with Vectrix Corp.) voided the warranty because of the publicly posted repair to the gear box.
They also blamed my gear box repair for damage which was in all likelihood caused by the Vectrix technicians themselves. (By not using a torque wrench to tension up the cables on the motor controller board. At least three Vectrixes in Australia have had smoldering cable connectors on the controller boards so far. But their technician does now finally use a torque wrench, and a certain staff member has left them I hear. I believe it may now be possible to get very good and knowledgeable service out of Vectrix Australia, maybe better than anywhere else. If you are an Ozzi reading this, go ahead and buy one if you can!)
I let them get away with it because it is not worth the risk and effort. And it might be more beneficial to the overall success of the Vectrix and other EV's to learn how to repair it in public, anyway. And interesting! But that is of course not every bodies cuppa tea, so better be careful...

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Were the other two Vectrixes you have ridden quieter?

I do not know what the brushing noise might be, maybe a safe opportunity to take a ride without a helmet presents itself and I'll have a listen.
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Any good mechanic with standard tools should be able to do it. Someone who also has experience in machining gears would be even better. A "Gears and Engineering" workshop.
If you lay the scooter onto it's side for a while before opening the gear box, then none of the original lubricant will be lost (but maybe your warranty).
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If you get this done, then ask the mechanic to take a guess at the best suited lubricant for the gear box, please!
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This one is really funny: Vectrix was told off for a part of their advertising that is actually true, on some level at least! No word about the inflated range claims, "silence", recharging time, etc. etc.
The ad breached CAP Code clauses 3.1 (Substantiation), 7.1 (Truthfulness), 19.1 (Other comparisons), 48.6 (Motoring) and 49.2 (Environmental claims).

Good luck with it!

Mr. Mik

The brushing noise you hear could be your brakes. The brake bads run very close to the rotor and could be rubbing.

Maybe we all talk about the same thing, in degrees.
What I heard in Mik's videos, I seem to recognise, but I can't say on my ride it is loud or disturbing, it just does not sound OK. Maybe it is the same problem, to a milder degree.

It is not just the wheel or the brakes, because it is only present when opening the throttle or over-closing the throttle. No noise (or far less) when coasting at throttle neutral.

I visited the dealership and proposed 1. let me try another scoot and compare, or 2. have a ride with mine and see if you feel that's normal. Guess what : no risk taking : "you know what? let's ask Vectrix".

How, I wonder, do you formulate the question?? "the guy hears a noise, is that normal?" "No not at all, he should consult a Ear Nose and Throat specialist".
I understand people try to get rid of problems ("oosh!! oosh!! go away !!!") instead of solving them. Poor america.

Cavalho

My other concern is a brushing sound that I hear in my engine when I am coasting at 20 kmh to 30 kmh. I only hear it when I am in a quiet parking lot without my helmut on. It is a brushing noise that is timed with the revolution speed of the wheel. Is that normal? I don't recall hearing it on either of the two other Vectrix scooters that I have ridden. Anyone else know what I am talking about?

Thanks.
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for what it is worth, i have noticed that if i do not keep the tires on my vectrix inflated to exactly the recommendations (42 PSI/back, 32/PSI front), i hear a brushing noise too. i assume it is the brakes.

While we are on the topic of gear noise, does anybody know what the factory fill of oil is in the Vectrix gearbox? (type and quanity) After looking at Mr. Mik's pictures of the dissassembled gearbox I noticed that the oil was very dark. Also, with the crummy machining of the gears, it would be nice to change the oil and remove the "break in" residue. I am sure it would make the gears and bearings happy!

Also, with the crummy machining of the gears, it would be nice to change the oil and remove the "break in" residue. I am sure it would make the gears and bearings happy!

I will certainly tell the repair man, on the first check-up, to do that, even if I have to pay.

I don't know exactly (because I haven't received the bike yet), but if I remember correctly (when I was speaking with the dealer), after 6 months or 6.000km.

Someone, correct me if I'm wrong.

I have noticed a "tick tick tick" sound from the rear wheel when coasting to a stop when there's no other sound to drown it out. The ticking slows down as the speed does, so it's something catching perhaps.

I think it's inside the drive casing and nothing to do with the rear brake.

Other than that, the drive under power sounds fine with no strange noises.

Has anyone heard anything like that?

I have the same as you describe, but I don't worry.

I have the same as you describe, but I don't worry.

Aaaaaah!

A feature then, LOL!

{quote]Aaaaaah!

A feature then, LOL![/quote]

Yep. That's the "Audible Rolling Indicator". Works backwards and forwards. Helps keep ya from getting off the bike when it ain't done moving! HAHA!! :-)

I have an undevelopped theory of what is causing this tick, tick, tick noise. There are tolerances in the gearbox, so the motor can move slightly back and forth with respect to the wheel. The motor is permanent magnet (brushless), which usually have a cogging effect, so that if turned slowly by hand, one would feel a light resistance, and then the motor would turn by itself to the next "cog". Now, when the wheel is turned slowly, the motor will move in steps, hitting the gears and thus creating the noise.

Still just a theory though. But if true, there is no reason to worry about the noise. The load and hits the motor and gearbox takes under load and at speed should be much higher than these cog steps. And it should be perfectly normal behavior for this motor/gearbox setup.

I have an undevelopped theory of what is causing this tick, tick, tick noise. There are tolerances in the gearbox, so the motor can move slightly back and forth with respect to the wheel. The motor is permanent magnet (brushless), which usually have a cogging effect, so that if turned slowly by hand, one would feel a light resistance, and then the motor would turn by itself to the next "cog". Now, when the wheel is turned slowly, the motor will move in steps, hitting the gears and thus creating the noise.

Still just a theory though. But if true, there is no reason to worry about the noise. The load and hits the motor and gearbox takes under load and at speed should be much higher than these cog steps. And it should be perfectly normal behavior for this motor/gearbox setup.

Makes good sense to me, nice theory and well explained, thank you.

P.S. Nice to know a few of us are getting the same thing.

Sounds reasonable enough to me, rgx. In fact, that's the best "theory" I've heard yet. Either way, I don't think it's a problem, or a wear and tear issue, even on the long haul. Just the natural behavior of high tech. :-)

Sounds reasonable enough to me, rgx. In fact, that's the best "theory" I've heard yet. Either way, I don't think it's a problem, or a wear and tear issue, even on the long haul. Just the natural behavior of high tech. :-)

A similar thing happened on the early K series BMWs. They sort of solved the problem by splitting a drive gear in half effectively having two gears side by side on the same spline and spring loading one of them to press on the other side of the teeth of the next gear being driven.

This worked fine until the spring failed and the rattle (in this case) manifested itself. It was too expensive to strip down the engine to replace a cheap spring, so most owners just put up with the noise.

I have an undevelopped theory of what is causing this tick, tick, tick noise. There are tolerances in the gearbox, so the motor can move slightly back and forth with respect to the wheel. The motor is permanent magnet (brushless), which usually have a cogging effect, so that if turned slowly by hand, one would feel a light resistance, and then the motor would turn by itself to the next "cog". Now, when the wheel is turned slowly, the motor will move in steps, hitting the gears and thus creating the noise.

Still just a theory though. But if true, there is no reason to worry about the noise. The load and hits the motor and gearbox takes under load and at speed should be much higher than these cog steps. And it should be perfectly normal behavior for this motor/gearbox setup.

I think you have nailed it, rgx! Thanks!

This fits nicely with what I found earlier.

Spinning the wheel by hand:
- there is a strong cogwheeling effect; there are 84 distinct, equally spaced positions in which the wheel stops (Determined by marking on the break disk with a marker pen).

- the initial resistance to turning the wheel is quite strong, then it gets easier once it is turning.

- the brakes are running freely.

http://visforvoltage.org/forum/3272-vectrix-real-world-testing-2-noise-levels#comment-18443

You are right about the magnets in the motor causing some of the noise when rolling the scooter back and forth at slow speeds. However, there is a more serious problem in the design of the gearbox that needs attention. As I have mentioned before, there is a binding taking place between the sun (pinion) gear and the planet gears on the Vectrix. There is zero design (or manufacturing) backlash between those gears. The only way any necessary backlash occurs is from clearance between the planet trunions and the planet gear needle bearings. This is why there are signs of burned (black) oil and pitting gears (Mr. Mik). When the sun gear pushs the planetary gears outward, backlash is in turn removed between the planet gears and the ring gear. As the gears bind and release it causes some additional noise at slow speeds. Gears are measured at their pitch line diameters and in the industry it is called MOW which stands for measurement over wires. Gears are measured with wire gauges hence MOW. I have made a couple of undersized sun gears. The gear is a modified metric gear with a non-standard tooth count. It took some time to aquire the proper cutters for the involute spline in the center and to set up the machine for cutting the teeth. The MOW on the replacement gear is .020" less then the factory gear in order to get a .005" backlash between all the gears, sun, planet and ring gear in my Vectrix. I have not been able to drive the Vectrix yet with the new gear as it has to go to the heat treatment facility before I can load it. However, just running the gearbox with no load, there is no binding and it is running smoother and quieter then it did with the factory gear. I will report back when I have ridden the scooter with the new gear installed. I told Vectrix about this and their attitude was "someone from quality control will get back to you"--they have not. This problem manifests itself with a noisy gearbox but will, over time, in some cases damage the gears down the road.

You are right about the magnets in the motor causing some of the noise when rolling the scooter back and forth at slow speeds. However, there is a more serious problem in the design of the gearbox that needs attention.

Yes, both the conditions co-exist, I think.

When the motor is working then there is no clunking because of the smooth interaction of the electromagnetic field of the windings with the magnetic fields of the magnets.

During slow speed pushing, without any throttle, the backlash between planetary gears and ring gear allows for the one side of the gears to make contact whilst the resistance moving towards the centre of the magnetic fields is being overcome; once it has gotten over the magnetic "hump", so to say, the magnetic force reverses in direction and causes the other side of the planetary and ring gear surfaces to make sudden contact - that's when a clunk happens.
The next clunk should occur about a moment later, when the direction of the magnetic fields reverses in "the valley" so to say. A slightly different clunk, milder.
I just tried this out: There are indeed two slightly differing alternating clunks, like the tick-tock-tick-tock of a clock, not tick-tick-tick-tick.

This clunking is completely independent of the whine, which is caused by the lack of backlash between sun and planetary gears.

And an uneven, fluctuating whine results from a modulation of the sun-planet-whine by an out-of-round ring gear.

Bingo! I think you guys worked it out!

In summary:

Clunking at low pushing speed is normal, all Vectrixes should have it. Probably totally harmless.

Whining is due to a design and/or manufacturing fault.

Uneven whining is due to a manufacturing fault or otherwise damaged ring-gear which happens to end up in a Vectrix with independently existing Sun/planetary gear binding.

One question that remains is: Why are some Vectrixes quiet, as promised?

During slow speed pushing, without any throttle, the backlash between planetary gears and ring gear allows for the one side of the gears to make contact whilst the resistance moving towards the centre of the magnetic fields is being overcome; once it has gotten over the magnetic "hump", so to say, the magnetic force reverses in direction and causes the other side of the planetary and ring gear surfaces to make sudden contact - that's when a clunk happens.
The next clunk should occur about a moment later, when the direction of the magnetic fields reverses in "the valley" so to say. A slightly different clunk, milder.
I just tried this out: There are indeed two slightly differing alternating clunks, like the tick-tock-tick-tock of a clock, not tick-tick-tick-tick.
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In summary:

Clunking at low pushing speed is normal, all Vectrixes should have it. Probably totally harmless.

It even has a name: "Cogging Torque".

You can look it up in Wikipedia.

This page has been added to the Vectrix Collaborative Handbook, please stay on topic!

Here is a link to the explanation for "Cogging Torque": http://en.wikipedia.org/wiki/Cogging_torque

I think if the power is under 350w,you can use nylon gear to replace the old one and then the sound will disappear. Over 350W,use metal gear is necessary for the safety.
That's my opinion. I hope it can help you