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Pegasus trapped in a human body on a motorcycle
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Discussion Starter #1
I have a little thought experiment going on.

I have seen many interesting valve actuation systems out there, some of them pretty advanced. Honda has the V-Tec thing going, and several others have come up with similar ideas. I have also seen that Ducati has come out with variable cam timing that works through the cam pulleys. Then there is the old school way from Rhodes, which uses variable duration lifters, available for HD pushrod bikes.

Now, what if they were able to take the variable duration concept from the rhodes lifters, and apply that to hydraulic finger followers, like in the ones used in the 1100 Shadow engines? I believe there are a few DOHC designs that use followers. If they were to make a Hydraulic DOHC design, that adapted the concept Rhodes used for lift and duration variability, and combine that with the timing variability used by Ducati... Imagine the possibilities!

Lower lift and duration figures for low RPM to boost torque, but also have higher lift and duration in the upper RPMs, combined with being able to time the opening and closing events on both the intake and exhaust sides.

Example... apply that to a base 140hp V-max 1200 engine. You could have low end like on a Venture engine, but maybe even have the ability to breath up top to support even higher redline and HP figures...

Maybe I'm just blowing smoke out my arse... idk, but this feels like an idea that could work.

What do you guys think of this idea?
 

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The hydraulic lifter subject is one dear to my heart because I've had lots of bikes with it and lots without the feature.

The best thing to me is not having to take a bike that is almost brand new (600 miles or so) for the first maintenance and on lots of bikes, the valves are supposed to be checked and adjusted if necessary.

A basically brand new bike will now be torn down, checked and if adjustments are needed, then hopefully it's screw and locknut and not 'shim over bucket,' 'shim under bucket,' replaceable bucket's or Desmo adjusters, which are very expensive because on some, the camshafts have to come out after the clearance is checked. VTEC valves like on Honda's VFR series add even more complexity and expense. Ducati now has a prototype Desmo, variable valve timing engine in production.

I will take just the plain and simple hydraulic lifters any day.:biggrin:

My 2012 Wing though doesn't even call for a clearance check until 34,000 miles but I once had a Ducati that had 3,000 mile intervals:mad:

The idea with variable valve timing is all over the automotive industry and actually adds HP in the higher ranges but allows more torque at lower rpm's.

Now, let's take it a step higher in our thinking to servo-electro mechanical valve actuation or air pressure activated valves as both are used now in formula cars.

With precise direct injection right into the cylinder itself, independent of the intake valves, the sky's the limit on intake and exhaust engineering.

Fun times!

Sam:):coffeescreen:
 

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Cams

There are plenty of ways to make it complicated. But any engine over about 750 cc can make good bottom end and top end power. I would rather they take what has been learned, and try and make them simple.

New vehicles are causing a lot of grief with complex systems, and difficult maintenance. A simple example. To adjust the alternator belt: First remove the right front wheel. Doing simple service, like changing the oil and spark plugs, is a big event on some vehicles.

Was just reading a bit about the Ducati system. Will be getting up close and personal with the shims on my Suzuki soon. Three bikes and they all have DOHCs and shims. But, try and adjust the exhaust valves on an F head Bentley.

On the early Ford side valve motors, there was no valve adjustment. New valves were over length. You ground the end down to get the correct gap.

Unkle Crusty*
 

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Nightfly
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I worked in a speed shop back in the early 80's. We were one of the first to carry and advertise the ability of Rhoads lifters. Pretty simple design as they had a larger hole for the oil to bleed back into the engine than most hydraulic lifters. This quicker bleed down caused a sound similar to solid lifters because of the faster valve closing rate at lower rpm. That clicking or ticking sound would gradually disappear as the rpm increased.

In selling these lifters we found that they worked best when using a high performance cam, more low end from and already low end type cam was not of much use, and there was no top end gain. Adjusting them was same as normal hydraulic lifters, zero lash plus 1/2 or 3/4 turn for preload.
 

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American Legion Rider
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Didn't I read somewhere that someone has come up with a way to eliminate the cam and open valves with air or some odd thing like that?
 

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Nightfly
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Porky has some good information. Formula 1 is usually at the edge of new technology development and they are the ones, I think, who developed pneumatic valve opening and closing. Now I see electromagnetic is also in the works. If perfected it would do away with a lot of reciprocating weight with better control of valve actuation.

Too bad we won't find any of this kind of technology under development by NASCAR. They are back in the stone age days. They do get a lot of RPM out of the old pushrod engines, but usually because of the exotic materials used in building the engines and better engine building techniques. But not because of advancement in technology.
 

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TR, yeah but when you sit on the straights at NASCAR and see them go by @ 200 mph, that's probably fast enough:biggrin:

There are so many advancements in vehicle technology right now, like the clean burning direct injected 2 stroke engines, for cars and bikes, New designs for the Wankle Rotary Valve engines, and other wildly exotic engines that somehow manage to turn a shaft so that the 'power' can be put to use.

I have subscribed to 'Road and Track' magazine for many years and the engine technology I see now is almost unvelievable: 12-13 second 1/4 mile rice rockets and others that make upwards of 350 to 500 HP out of a 2 liter, 4 cylinder engine. V8's and V12's in family cars, wagons and SUV's that have up to 650+ horsepower and rich soccer Mom's can drive their kids to work in them. 3 cylinder engines are becoming popular, some with supercharging and some turbocharged.

Diesel tech is going through the roof too.

Fun times.

Sam:)
 

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Nightfly
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When does 200 mph become boring? When it's NASCAR. Most every sport you can think of plays in the rain. Football, baseball, cricket, Australian Rules Football, Canadian football, soccer, Formula 1 racing, motorcycle racing but for some reason NASCAR people are horrified of driving in the rain.

It's still people driving in circles, and yet people pretend to watch. After a few laps it's difficult to tell who the leader is. Some people, Americans, believe NASCAR is the most popular sport in the entire world. What can I say. Drivers are nothing more than high paid pitchmen, all that's left is to tattoo their sponsor's name on their forehead.

And then they have the biggest race of the year, their Super Bowl, The Daytona 500, as their first race of the year. Maybe baseball should have the World Series in April.

To me NASCAR has become totally boring. I loved it back in the 60's and 70's when you knew the cars, and each car had it's factory engine, modified of course. And the car itself actually looked like the car you could buy on the show room floor. 427 Fords, 426 Hemi, then reduced to 305. Pontiac 421, actual Pontiac engine. And there was Smokey Yunick and all of his innovations, which are far too many to list on this thread.

I would find NASCAR interesting again if they made it a 25 lap race or maybe a timed event. It's far too long now, it's like watching a line of same cars going down the race track separated only by color and driver name. How do you tell a Ford from a Toyota? By the decal. For me I'll take motorcycle racing as that requiring the most talent and for high concentration. And the races do not last an entire afternoon. Formula 1 is interesting because of the types of tracks they race on and the super high degree of technology found in all the cars.

If I do watch circle track it's dirt track racing for me. Those guys are on the edge and drive balls out. What kind of racing is it when the drivers say "I just hold the pedal to the floor all the way around and steer?" IMHO it's a recipe for boredom.
 

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To me, stock car racing is in the dirt. NASCAR stopped that years ago and went downhill fast. I'll watch a start just to see if they crack up immediately then off it goes. It is too boring now. Speed isn't everything. I want to see skill and strategy. Might be some of that at the last 10 lap area. I don't know. Been too long since I felt the need to look. That's just how boring I think it's become.
 

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If I do watch circle track it's dirt track racing for me. Those guys are on the edge and drive balls out. What kind of racing is it when the drivers say "I just hold the pedal to the floor all the way around and steer?" IMHO it's a recipe for boredom.[/QUOTE]

Every town should have a speedway track.
The 500cc bikes are best, but they also can run 3/4 midgets with 650cc bike engines, the old full size midgets, with 200 cubic inch maximum, and now the new full size with 400 CI.
A search of Ivan Major will lead you to the best bike rider.

There are tracks in the Southern states. Riders and drivers would go to NZ and Ozz during the US winter. Bob Two Gun Tattersall is a name I remember.

Unkle Crusty*
 

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Nightfly
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I keep my bike in the garage of an old time dirt track racer. Photo's on the wall of his glory days years ago. That kind of racing is almost non-existent around here now. But we do have a great 1/2 mile banked Sprint car dirt track for American Sprint cars. Williams Grove Speedway is the name of the track. Some of the best racing in the country, with the World Of Outlaws appearing a few times during the season. Good racing, lots of talent on hand with balls to match...
 

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Nightfly
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To me, stock car racing is in the dirt. NASCAR stopped that years ago and went downhill fast. I'll watch a start just to see if they crack up immediately then off it goes. It is too boring now. Speed isn't everything. I want to see skill and strategy. Might be some of that at the last 10 lap area. I don't know. Been too long since I felt the need to look. That's just how boring I think it's become.
Cowboy, if you were to watch the current version of NASCAR, you'd be asleep by the 10th lap. It IS that boring... Many watch for the hopeful fights at the end of the race.
 

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We get a kick out of the last race of the year here. Several of the locals if they didn't do good with this years rattle trap just add one last race in the end. The figure 8 demolition derby. It is a crack up.I have a nephew that raced modifieds until he got married. Couldn't afford both so the racing got sidelined. The way he popping kids I think his racing days are gone. It was fun having someone that close to yell about with the other fools.
 

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I have no idea what Victory uses for valves. They run a pair of dual overhead cams, one pair per cylinder. As you would expect there is no lifter involved in an overhead cam but somehow they are hydraulically adjusted. If you let the bike sit long enough between rides you even get to hear them pumping up, just like hydraulic lifters do, with the ticking sound followed by a nice quiet valve train. The only place I can see for hydraulics would be at one end of the rocker arm. With 2 valves per rocker my bet would be at the cam end.
 

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Oldman, here's some Victory info in an interesting web-site:

"16. Victory engines have overhead cam roller rockers actuating the valves. These roller rockers increase horsepower, are lighter than push rods that permits the engine to accelerate faster with increased throttle response, engine breathes better, reduces wear and tear to the valve stems and guides, creates a better ratio, improves lubrication along with much less friction. These components is what you see in racing engines. However, if the rear cylinder hydraulic valve lifter were to fail the engine must be lowered out of the frame to remove the top valve cover. Odds are, it won't fail."

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&cad=rja&uact=8&ved=0CE4QFjAK&url=http://www.jamesrussellpublishing.biz/victory.html&ei=NkmMVNH7H4SgyQSQ24CQDA&usg=AFQjCNFsH30SM7hxx5SOA3adZ7D2fEsMLw&sig2=zDSyi7SUvdgm82LpxUPb6A

Sam:coffeescreen:
 

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I have a ball at NASCAR races. I'm usually either hanging out in the garages or behind pit row making a pest of myself asking questions, or ogling the scenery that's partying on the infield. I don't actually watch much of the race itself, but it can be fun if you're standing right by the wall and the pack roars by. Watching it on television would bore me to tears though.
 

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Retired twice: Navy and as a govt contractor
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Eye big difference being there.

Formula 1 is my favorite, followed by the European Sedan series and then the lorry racing :)
 

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I thought I was the only one that watch those big things.:D They amaze me.
 

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If you can get to a track where it is happening, the motorcycle GP circuit is great fun to watch. I did that many years ago at the Riverside Raceway track and still have vivid memories of those races.
 
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