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Anyone ever considered or heard of a hydraulic variator?

Posted: Fri Mar 01, 2013 1:32 pm
by Mjh787s
This is absolutely theoretical, and I do not possess the machining and fabricating skills to do anything like this, but food for thought and good discussion.

Has anyone considered, thought about, or heard of using a hydraulic actuator to control variator movement?

I was thinking something like this:
http://www.ramclutches.com/zen-cart/ind ... ge&pID=678

It is your basic hydraulic throw out bearing. It could mount to the case behind the variator, custom machined variator, no rollers, roller sockets, ramp plate, or anything, just a surface for the bearing to fit to the variator.

The driver could control the hydraulics via left hand throttle equivalent, thumb slide (like ATV), or foot pedal.

Obviously a strong center spring is needed in the back, maybe a 2k or more, reinforced welds anyone?

Belt stretching is a concern, as you could exert quite a bit of pressure.

User would be in control of engine RPM, and belt movement through the sheaves instantaneously.

Just throwing out as a thought, again, as wheelman and Baka can attest....I am NO expert with scooters, can't even get mine do do what I want.....Just trying to see if this is an interesting topic on the board.

Re: Anyone ever considered or heard of a hydraulic variator?

Posted: Sat Mar 02, 2013 1:12 am
by Wheelman-111
Greetings:

Subaru, Nissan and others use computer controlled CVT in many models in search of best gas mileage. "Belt" is metal. Works very well. You can select a fixed ratio of six positions to simulate a six-speed on the Subarus. Sort of eerie to see the engine rev to redline and stay there at WOT. FULL MANUAL CONTROL IS INTRIGUING, BUT WHAT POWERS HYDRAULICS?

Re: Anyone ever considered or heard of a hydraulic variator?

Posted: Sat Mar 02, 2013 1:44 am
by Mjh787s
Wheelman, so glad you replied.

I am familiar with the conical, chain belt drive, single teroidal, and dual teroidal cvt setups.

In clarification, this post pertains to scooter applications only. As I know we aren't the first to dream up a non-roller cvt control.

The hydraulic force for the throw out bearing would be minimum. I think a twist of the left wrist would provide plenty force,

Another take at it would be to implement a throw out lever (fork) and traditional throw out bearing and control via cable. A left handed throttle equivalent could control throw out.

Re: Anyone ever considered or heard of a hydraulic variator?

Posted: Sat Mar 02, 2013 2:17 am
by motormike
I like the application to the racing and performance side of moto-scoots.... :thumbwink:
The general public would simply frown and announce to the salesman that "clutching" and "shifting" are the very reasons they want the simpleness of the scooter in the first place, so, "No, thank you" to the idea... :sad:
I'm trying to imagine how this would feel if I were controlling the variator sheaves, and where the control benefits the most.

Re: Anyone ever considered or heard of a hydraulic variator?

Posted: Sat Mar 02, 2013 4:44 am
by paulpauly7
maybe on a race bike on the track doing laps but not for a road bike a corsa bbk should be enough

Re: Anyone ever considered or heard of a hydraulic variator?

Posted: Tue Mar 05, 2013 2:25 am
by Mjh787s
I would imagine that you would use a hydraulic or cable controlled variator similarly to a clutch, in that you would ride the desired rpm.

The rider might have a best sense of torque rpm and hp rpm, and manually keep the engine in that rev range.

The rider can use the downshift to engine break also.

The factor of roller weight compromises will disappear as now you can have your engine at perfect rpm from takeoff to full speed.

I often wonder on my weights if a few more grams would do x, or lighter grams do y. A manually controlled variator would guarantee you get the most out of your engine.