You just pouring more and more oil in the fire 
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Hey there every body,
Iām not expecting to go to Gear Drive myself, but wanted to mention something cool on the technology side.
With regard to gears, after they are basically finished in terms of machining them and cleaning up the edges etc, there is a sweet finishing process that is used on some gears. It might be a bit much for Electric Skateboard gears, but then again it might allow them to be made more light weight and still hold the force and have long life.
I am referring to āCase Hardeningā of the Gears. There are several ways to Case Harden Gears. But basically, you start with a gear, say steel that has some ability to bend elastically when subjected to higher forces. Then, you infuse the outer 1 or 2 millimeters of the gear with extra molecules of carbon or hydrogen molecules, I forget which one.
The result is the extra molecules make the outer 1 or 2 miliimeters of the entire gear, including the teeth extra hard which usually means they become more brittle which means they can break off.
But underneath that extra hard 1 or 2 millimeters of extra hard metal which provides for long service life due to low wear, that is where most of the gear material is a steel that can deform elastically somewhat.
So if you have some kind of an incedent which might normally bend or break a tooth off, the outer shell of harder material might crack, but the tooth will bend a little bit elastically and return to normal position, not break off etc.
This wasnāt the best explanation of āCase Hardeningā, but look it up if you are thinking about manufacturing a super sweet gear drive.
Its like extra molecules are pressed in over time and under pressure while the gear is heated. It results in a linear "Diffusion density between the harder outer āShellā and the more flexible inner steel.
!
Take care 
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A pom wheel gear saves weight.
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not beef. theyāre simply a fraud we like to avoid
Iām a big gear drive fan. I have the original AvX drives and the spiral bevels from Morris. In my experience, gear drives are very much an Apple experience. They are generally designed to work exactly one way, and if you donāt like it, donāt buy it. There is generally one gearing ratio, one truck mount option, and one wheel type. However, when assembled correctly, they require extremely little maintenance and work perfectly for thousands of miles.
As for the differences between drives, it really comes down to which solution most closely matches your budget, and your application. Kaly drives only fit on pneumatic wheels and channel trucks, so they are a great choice for a mountainboard build. The original AvX drives only fit CNCāed trucks and flywheels, so they are a good choice for a street board with Foamies.
There are four main types, straight, helical, herringbone, and bevel.
- Straight gears are cheaper and easier to design, but are the loudest.
- Helical gears are slightly more expensive, but they require thrust bearings to deal with the axial loads produced by the gears. Helical can be quieter than straight if the drive was designed for that.
- Herringbone gears are more expensive than helical, but they do not require thrust bearings. The only current Herringbone design is also the quietest gear drive by far, but time will tell if this is a fluke or a characteristic of this design.
- Bevel gears are a special design that allows motors mounted at a 90 degree angle to power the wheels.
One thing to note about gear drives is that the size of the drive is often determined by motor clearance. In a two straight gear setup, the radius of both gears must be greater than the radius of the motor and the truck plus about 5 millimeters. This is why some drives have attempted three gears in order to decrease the required size of the wheel gear.
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the 4:1 fixed ratio of the Kaly drive makes it less optimal for and offroad mountainboard
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True. Above 150kv motors you would probably want at least 5:1 gearing for a real mountainboard.
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Lots of strange info here.
Iāve heard dead quiet straight cut gears that are well aligned with the correct lube in the correct amount.
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Not really the case with moon drives if you get different adapter for the hanger. The wheel adapter as well fit different hubs and the gear ratio can be changed by choosing between different motor gears.
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the 4:1 fixed ratio of the Kaly drive makes it less optimal for and offroad mountainboard
Would you suggest using those drives on a 35 degree riser with a vanguard deck instead?
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The moon drive is the exception that proves the rule. When you can only list one drive like that of the dozen that are available, Iād say itās accurate.
the Kaly has 30 degree, and I want more on the front truck and less in the backā¦ I added 7 degree wedges front and back so I have a 37-23 split angle
pick your board and pick your specs itās pretty much personal style and preference from there, my comment wasnāt about the board as much as it was about an onroad vs offroadā¦ 4:1 isnāt a great ratio for an offroad board, onroad itās awesome
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Also other drives have the option to change the gear ration. Not all, for sure but itās also not right to say there is only one gear ratio in general. For etoxx drives you can as well get different wheel adapter. I think thatās possible for some other drives as well.
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I think most drives allow you to change to a different pinion?
Whatās not to like though? From what Iāve read, they provide low rolling resistance, high efficiency, excellent torque response, have very low maintenance and are much less prone to failing as compared to a belt drive! I currently own a boosted board [belt drive] and have changed far too many belts in the last 2 years.
The only functional down side of gear drives I can think off, is the noise, if I were to get a straight cut gear drive. Iāve been looking at Moonās drives and other straight cut gear drives, chanced upon this video and realized the noise was an absolute deal breaker for me. The pitch of how this gear drive sounds just annoys meā¦ 
Iām sure there would be some that loves the sound, I can imagine it can amazing sound to hear in an esk8 race.
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Hey @Venom121212 itās you!
Also @Rake, maybe youād wanna take a look at this.
Thatās my board, and i swapped from the straight gears to the herringbone.
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WOW. Is it really that quiet in real life? Thatās pretty darn amazing if it is - Herringbone Gears may be the key to checking all my boxes in a gear drive!
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Straight cut is louder than belts but only marginally, sorry you donāt like the sound. I love it 
That video is of the beta drive before I took it apart and regreased it if all factors are to be considered. Also the audio is coming from my sonās cheap gopro on a selfie stick 
Iād love to try out spiral or herringbone but the price being %150 more expensive is kiiiind of a deal breaker for me.
@linny that herringbone ride looks a bit more leisurely to me I was hitting 30 mph in my video for reference.
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Ah my bad @Venom121212 didnāt mean to compare it like that. Yea iād say i was going 25km/h or so on the herringbone.
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