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Found this blog and thought I would share it so folks can get a better understanding of what a CVT is appreciate many on here are well versed with the workings but others won't be
 

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Jolly Well Done maccecht ! I think I understand now .
 
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One technical thing that article gets wrong, as many others do also, is describing a CVT as having an infinite amount of ratios. This is totally incorrect. There is a very finite amount of ratios, governed by the underlying electronic and software鈥檚 output precision, and motor. In the Burgman鈥檚 case, a stepper motor, is used. Typical steppers have 200 steps per revolution, but can be micro stepped for smaller increments. I doubt the burgman actually achieves more than 500-1,000 ratios since mechanical imperfections on the sheaves and belt assemblies, combined with backlash of the stepper and other parts in the CVT, will result in the belt staying in a preferred circumference, despite a small step of the stepper.
The other big issue of labeling it 鈥渋nfinite 鈥 is, that they actually only allows ratio steps within it鈥檚 minimum and maximum diameters. No 20:1 ratios, no 1:20 ratios. That鈥檚 why the clutch has to slip when you鈥檙e easing forward at a traffic light, and why the revs can鈥檛 drop down when you鈥檙e doing 75 mph on the highway.
Technically correct articles refer to CVT鈥檚 as continuously variable, which is a much better description, than using the word 鈥渋nfinitely 鈥..

Now back to your regular program馃槈
 

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yeeah, infinite is incorrect, however, it does sound a little better than "butt-load"
 

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Technically, Infinitely Variable Transmission is a particular thing in engineering (IVT).
It鈥檚 a CVT whch varies all the way down. to zero - and even reverse.


鈥滻nfinity鈥 as a popular concept is not the same as used in maths and engineering, where things can be 鈥渃ountably infinite鈥.

In an electrically controlled system, yes it鈥檚 true to say there will be innumerable small steps in the cvt element, but innumerable is synonymous in common useage (meaning a $#/楼load)
(only the 650 and the Type M being electronic)

IVT systems have additional elements including planetary gears that extend the ratios beyond a 650 style system.

In a technical article it鈥檚 best to save 鈥渋nfinitely鈥 for IVTs rather than CVTs in general.
 

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Looking at the older freebie service manual for the AN650, it would appear our Burgmans actually use a traditional 2 wire DC motor, in combination with a linear position sensor. Not an actual stepper motor.
My bad.
 

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The only thing I have to say is the 650's "E-CVT" is leaps and bounds better than any conventional CVT on the market.
 
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