Flettner, after the ktm debarkle, go easy on showing your results. no point being the FREE R&D for someone elses profit mate. unless of course your happy with the situation![]()
Zipped them out to shed before she got a chance to see them.
Ha Ha, yes Breezy, KTM are spying on us. What to do? They could pay me NOT to post stuff on this forum
Or perhaps these pictures could be a red herring and the real development results are locked away inside my secure research facility deep in the Forrest.
Or perhaps there is correspondence at this point with their opposition, I'm not saying nothing.
Or perhaps this is all bullshit.
I've got KTM's next generation injection system here now, only if I show it off, it will be KTM's next injection system! (when they find the limitations of the system they have now).
It's well suited to run on a 125, just saying, plenty of injection time available.
It goes back a fair ways too....When I was a kid, at one Lady Wigram meeting, I remember seeing a group of poms wearing BRM overalls around the tail end of one of Hec Green's RA Specials. The next season's BRM rear suspension was a copy of Hec's. That was their first rear engine car so it would have been probably Jan '58.
Yachting has many examples too....
Weekend’s activity was to make a mounting system for a spring scale to measure the torque of the dyno absorber unit. I know it’s pretty crude, but I don’t want to frig around with reviving some rooted electronics bits any more.
Some might even think it’s a bit fishy.
So it’s almost ready for the big "tell all or nothing runs" when I’m back in a couple of weeks.
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Willy, it is a water brake style absorber. In principle the design has been around for ages, eg Heenan & Froude ( you should know this, from the old mother country). Essentially it is filled/partially filled with a constant flow of water, presumably the more water the more drag, hence load. The energy being dissipated thru heating the water. The flow is controlled via the inlet valve. With these and this one (TRIK) , when operating at a constant speed, the software controls a variable valve based on speed feedback.
On the bottom left of the first pic you can see a ½ in brass gate valve. This will be my flow control device if we can’t get the software to both read and control the valve. I guess a feature of the absorber is that, unlike an engine, it’ll be relatively insensitive to the water temps.
I've been around for ages too; my first dyno brake was a Heenan & Froude. The peculiarity about it was that the amount of braking was controlled by two slides moving radially in- or outward between the pump rotor and pump stator. You had to move those slides by turning a hand wheel on the penduling pump housing. But as soon as you laid a hand on this wheel, the pump housing moved a little and the braking torque indicator hand moved as well - not a great way to achieve accuracy.
Controlling the water flow was a better option, but not by much, because it would vary the water pressure in the system, which would make the rubber hoses between the stationary valve and the penduling pump try to change their curvature, once again exerting unwanted torque on the pump housing.
Then there was the pump characteristics. The pump's absorbed-torque rose with rpm alright, but it rose nowhere as steeply as the torque curve of a racing two-stroke. So with the engine running somewhere in the torque dip below its power band, when you reduced the braking torque in order to let the revs climb a bit, the engine would wake up and the revs would shoot up to almost maximum rpm where its torque dropped off.
In time I could more or less improve this behaviour by doubling the pump rpm and tripling the water pressure but it was never easy to sample a power curve.
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