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omnivalves-anti reversion intake valves
by
CoolAirVw
on 04 Jul, 2007 20:52
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I did a search and found no thread discussing these.
Lets replace our intake valves with some of these!
(Before flaming me and bashing these valves read the thread from speedtalk.com. There are some hardcore guys and they bashed the valves to death, then the developer of the valve Mike Tieman (tieman55) came onto the forum and answered their questions and it seemed to me he made them believers or at least opened thier minds to it a little bit.
Here's the most interesting discussion of the valves.
http://speedtalk.com/forum/viewtopic.php?t=4374Here is their website.
http://www.omnivalves.comHere Jake Raby of Air Cooled Technology was given some to test (no results yet)
http://forums.aircooledtechnology.com/showthread.php?t=411
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#1
by
hillfolk'r
on 04 Jul, 2007 20:59
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i use these
they are so big,you can use one per cylinder,and let them do double duty :lol:
yes that is a stock 1.6 piston
they are so big,they dont even fit in the cyl
the stem is like 9/16
i also use these wristpins for pistons
:lol:
thats because of this
WOLFGANG WILL KICK DR.Z'S ARSE ANY DAY OF THE WEEK!!!!!!!!
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#2
by
jtanguay
on 05 Jul, 2007 09:32
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:lol:
if these are as good as they say they are, they must cost an arm and a leg
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#3
by
foxracer1
on 05 Jul, 2007 14:23
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VEE DUB in da house!!
love those comercials
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#4
by
Turbinepowered
on 05 Jul, 2007 15:24
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So basically they put a ring-shaped reed-type valve on the valve stem of the intake valves, and are hailing it as an enormous breakthrough?
I dunno... I mean, for an otto cycle, that has some valve overlap, I could see this being a good thing, but for a diesel not nearly such a huge development since the lack of overlap means that exhaust gas can't push backwards into the intake.
Also, the author seems to be ignoring the fact that there are other ways to open, and more importantly close, valves much more precisely and quickly, namely through desmodromic valvetrains. And desmodromic, coupled with VVT and VCT technologies could provide both differences in valve open/closure speeds and timing, with much more precision than a floating, air pressure controlled device within the valve itself.
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#5
by
Northern RD
on 05 Jul, 2007 15:51
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So basically they put a ring-shaped reed-type valve on the valve stem of the intake valves, and are hailing it as an enormous breakthrough?
I dunno... I mean, for an otto cycle, that has some valve overlap, I could see this being a good thing, but for a diesel not nearly such a huge development since the lack of overlap means that exhaust gas can't push backwards into the intake.
Also, the author seems to be ignoring the fact that there are other ways to open, and more importantly close, valves much more precisely and quickly, namely through desmodromic valvetrains. And desmodromic, coupled with VVT and VCT technologies could provide both differences in valve open/closure speeds and timing, with much more precision than a floating, air pressure controlled device within the valve itself.
Good Lord, another Ducati lover,...
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#6
by
Turbinepowered
on 05 Jul, 2007 19:54
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Good Lord, another Ducati lover,...
Ducati lover, me? Not really. I'm not into the whole "I have to go
as fast as I can" thing that seems to be the lure of Ducati.
No, I just like the technology. It's precise, it's efficient, and it's incredibly complex while at the same time being absurdly simple. It solves at least one problem and allows for more variability with relation to valve timing, so what is there to dislike?
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#7
by
Northern RD
on 06 Jul, 2007 10:14
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Good Lord, another Ducati lover,...
Ducati lover, me? Not really. I'm not into the whole "I have to go as fast as I can" thing that seems to be the lure of Ducati.
No, I just like the technology. It's precise, it's efficient, and it's incredibly complex while at the same time being absurdly simple. It solves at least one problem and allows for more variability with relation to valve timing, so what is there to dislike?
What`s not to dislike??
Well, having lived with a 900SS for three years I can honestly say that during the 2% of the time that the duck was running well, it was a dream: the other 98% of the time it had all the tractability and grace of a garbage truck as a daily ride. After some 37,000km I got fed up with the constant tinkering and sold it to someone who paid me a Kings ransom. By way of comparison, the `85 FZ750 beater that I use a daily ride has over 108,000km on the clock, has never needed a valve lash since I purchased it at 22,000km, and is STILL within correct valve spec. It`s a better bike in ever MEASURABLE way(discounting immesurables like 'mystique', 'heritage', etc) and doesn`t require half the effort to maintain. Put more simply, the FZ750 allows me more riding time than the Ducati wheras the Ducati demands WAY more screw driver time for the little it gave in return.
My 2 cents,...
Apologies, meant to say '-like', not 'dislike',...
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#8
by
Turbinepowered
on 06 Jul, 2007 10:35
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Put more simply, the FZ750 allows me more riding time than the Ducati wheras the Ducati demands WAY more screw driver time for the little it gave in return.
Can't really say that I can vouch for Ducati durability and driveability; I don't own one, don't own a motorized bike at all (though I do have almost 2k miles on my bicycle). But I honestly can't believe that
all of that wrenching time was caused by the desmodromic valve system. Maybe I'm wrong, but I just find it hard to believe.
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#9
by
Northern RD
on 09 Jul, 2007 10:29
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Put more simply, the FZ750 allows me more riding time than the Ducati wheras the Ducati demands WAY more screw driver time for the little it gave in return.
Can't really say that I can vouch for Ducati durability and driveability; I don't own one, don't own a motorized bike at all (though I do have almost 2k miles on my bicycle). But I honestly can't believe that all of that wrenching time was caused by the desmodromic valve system. Maybe I'm wrong, but I just find it hard to believe.
Unfortunatly the Desmos` advatages are more appant than real. Take for example the fact that one of the designs adavantages is that it manages to avoid the vicious spiral between inreased lobe lift and increased valve spring pressure. Desmo advocates make a point of mentioning this but fail to explian how this is an advantage in the real world as an increase in cam duration almost always leads to increased power at the upper end of the power band, usually at a speed beyond that which the rocker set-up in a desmo can fallow without catastrophic binding. Cagiva managed to side-step this nicly by using simply, low-tech OHC in thier v-twins and they`ll rev reliably well beyond what a duck would(I`mm sure someone out there will argue this!).
As well the Ducati calls for a valve lash something like every 15-17,000km with the desmo valve train wheras the FZ750 I mentioned above scheduals it`s first valve spec check at 100,000KM, that with it`s low tech shim and bucket system.
N.
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#10
by
Northern RD
on 09 Jul, 2007 10:31
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Almost forgot: 2,000 miles on the bike? Good stuff, keep it up!
N.
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#11
by
CoolAirVw
on 09 Jul, 2007 18:15
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Wow. This thread is the king of the hijack.
7 posts about Ducati's, 1 post about VW commercials and 1 post with non-sense pictures (very funny though)
Oh well. :roll:
Hey at least explain this comment. (or maybe a link I could read)
...... namely through desmodromic valvetrains. And desmodromic, coupled with VVT and VCT technologies could provide both differences in valve open/closure speeds and timing, with much more precision than a floating, air pressure controlled device within the valve itself.
Oh, nevermind I Googled it,
http://www.teamyikes.com/desmo.html
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#12
by
935racer
on 09 Jul, 2007 18:51
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I'd definitely be interested in hearing some 3rd party results.
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#13
by
lord_verminaard
on 10 Jul, 2007 07:29
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Well, the site is hard to read and full of typos, but they dynoed a built LS1 engine and it made 440 ft/lbs of torque at 1500 rpm, which I find really hard to believe. Apparently they are getting engines to idle at 200 rpm and make torque at that speed. Sounds neat but I'd like to see it to believe it. They also said in the site they are testing a Cummins 6BT engine (they spelled Cummins wrong BTW) but testing is not complete. I am curious, that's for sure.
Brendan
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#14
by
Chestrockwell
on 11 Jul, 2007 17:35
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Sounds like they're desparately trying to replicate an electric motor.