Direct gear driven primary drive system

[Storkfoot]

Back in 2013, Casa put this system in their catalogue, albeit they referred to it being “in preparation.” What happened to it?

[ULC Soulagent]

Probably sapped too much NRG, extra weight too make it viable

[Warkton Tornado No.1]

Power Transmission between aligned centres tends to carried out by three common methods: belt, chain & gear.

When I saw the image some years ago, I considered the disadvantages of gears in the application of the primary drive.

Expense for initial set up
Expense for ratio changes, bearing in mind that not only might all three gears need substituting as well as the idler gear position would need to be variable
Complexity & time required to measure tooth gaps & alignment of PCD's
Noise & vibration (gears have a tendency to 'ring')
Inertia due to increased mass would not make for slick gear changes, the consequences of which would be shock loads to the gearbox.

IMO gears have no advantages in this application. The fact that they can be more efficient in power loss terms (although that may not be so in an oil bath) is far outweighed by the disadvantages.

BTW. In anticipation of another comparison, chain drive is more efficient than belt drive. Car manufacturers are also tending to revert to chain cam drives because of the longevity compared to toothed dive belts. Apart from Rolon chains as sold by many of our dealers......

[Storkfoot]

The motivation must have been to maximise the power transferred from the crankshaft to the rear wheel, I suppose. At the time I saw it, I thought it was an interesting idea although I suspected the Cush drive may have needed some beefing up.

Now, 7 years on, I am just intrigued as to how Casa tested it and what their findings where. There again, how many companies share their failures ( I presume it was) in public

[missing lynx]

Isn't that how geared vespas do it?

[Storkfoot]

Isn't that how geared vespas do it?

Yes, but they have a proper Cush drive set up and only two cogs.

[jonashford]

Vittorio showed us this wen we visited his museum & workshop on the way home from Avignon in 2013 dont think it was practical, He was however working on lots of different projects

[Storkfoot]

Vittorio showed us this wen we visited his museum & workshop on the way home from Avignon in 2013 dont think it was practical, He was however working on lots of different projects

Fair play to him for giving it a go.

I wonder what happened to Tino’s belt drive system too

[a.lo]

Surely that front sprocket cush drive would not work because it would move away from the middle sprocket?