MTK

Potentially lower maintenance too, as long as alignment holds. Can't tell from the photo if the motor is driving the large sprocket or if the large sprocket is being driven by the belt. The prop looks smaller so it may be the latter

MTK

Okay from the latter photos it's a belt double reduction set-up similar to what servos use. Curious to know how much pitch he's turning. The set-up would produce tremendous torque for relatively low current particularly at mid throttle. It wouldn't surpise me if the prop was 19x19.

guille2006

Undoubtely the system develops more torque and less rpm; so he can choose to use more pitch or more diameter.
I made some numbers for gearboxes and the first result indicates me that a 50% rpm gives a gearbox in no less than 800 g. This system is for sure less than that.
I suspect that we will see that solution more ofetn from now.

Ricardo M.

Seems that everybody was impresed with Akiba flying style, very slow and close. Another picture of his Hacker motor development.

MTK

Put a cone on it....it will spool up a DA100, no problems.

Seriously, this is good stuff. Anybody know what prop size was run?

sarashina

Unfortunately I have no idea about the prop Mr.Akiba use. But I am hearing merits of this system from my friend who relate to Mr. Akiba. This system is less friction, more silent than its gear down. Besides, it is easy to maintain. Deceleration ratio seems as same as Hacker's gear down.

sarashina

Malcolm H

Simply scaling the relative diameters of the toothed pulleys as seen in the near side view above gives me 40/15.5mm or 2.58:1

Overall ratio is 2.58 x 2.58 or 6.6:1 ie within limits of this crude measurement the same as 6.7:1 for the standard gearbox.

Malcolm

MTK

Do you know if Hacker has the belt reduction unit available as a retrofit on other motors?

sarashina

I guess Hacker will not prepare the belt reduction system you think. Mr. Akiba acquired the motor without a gear box and a pinion gear, and then he personally made this unit.

sarashina