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José_quiñones
| | Posted on Thursday, December 11, 2003 - 08:55 pm: | 
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quote:Where are Blake and Jose when you really need them???
Y'all are doing great on your own. |
Blake
| | Posted on Thursday, December 11, 2003 - 08:57 pm: |
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We're busy wrestling on another topic.  |
José_quiñones
| | Posted on Thursday, December 11, 2003 - 08:58 pm: |
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quote:Does Harley not have any sort of REAL race development program?
You need to read this for some historical perspective:
Obituary: Harley-Davidson VR 1000, 1988-2001
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M1combat
| | Posted on Thursday, December 11, 2003 - 10:26 pm: |
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So they don't then... Not since 2001 anyway. So, what do you think the chances are of HD getting deeply back into it? |
Blake
| | Posted on Thursday, December 11, 2003 - 10:43 pm: |
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They are into Drag Racing with Vance and Hines. No road racing other than Buell supporting the various Buell teams in FUSA and possibly AMA FX. HD is heavy into the dirt track scene too, almost forgot. |
Hootowl
| | Posted on Thursday, December 11, 2003 - 11:10 pm: |
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M1combat,
Ah. I see the light. |
Aesquire
| | Posted on Friday, December 12, 2003 - 11:38 pm: |
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I chose a Buell because, not in spite of, the low revs. After buzzing my butt cross country on my GS1100, I swore off jap IL4's.
Last week I was chatting with a Repliracer rider, he had a 11000+ redline, but no power under 7000 to write home about. Let's see, my M2 runs happy 2500-6500. I was surprised we had nearly the same rpm range! ok, he had more total power (120 crank hp) and his bike does wheelies at will too.
I have often wondered what a Buell with a Honda RC51 engine would be like. Probably like a RC51 that handles better. (heh heh) |
M1combat
| | Posted on Saturday, December 13, 2003 - 02:24 am: |
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Yeah, that's what I like about mine too, but for RACING.... Not ME racing... FACTORY racing.... |
Brion
| | Posted on Saturday, December 13, 2003 - 12:31 pm: |
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M1 to put it simply it is an inertia and piston speed issue. First, since being a pushrod engine the valve train is put into motion by the lift of the cam lobes, but has to return completly reliant on the valve springs. So all of the weight of the pushrods, rocker arms and valves have to be reversed by the springs. If it does not return immediately to the cam lobe on the way back the duration is increased more than design and the gap between the open valve and the piston returning to TDC is decreased and possibly make contact. This is why overhead cams have an advantage the only inertial force having to be reversed in direction is the valves. The other component is piston speed, if an engine has 4" stroke traveling at 1000 rpm it travels 8,000 inches per minute if an engine has 2" stroke at 1000 rpm the piston only travels 4,000 inches per minute. The further and faster a piston travels along the cylinder wall the more friction it creates. Therefore in an engine with 4" stroke turning 7,000 rpm an engine with 2" stroke can turn 14,000 rpm to obtain the same piston velocity. The other thing to keep in mind is that they are liquid cooled which is much more efficient than air. However they can not match the low end torque which is created by the lever arm of the crank throw. Balance can help but is not the main issue. Ok now everybody jump on me.
Brion |
Unibear12r
| | Posted on Thursday, December 18, 2003 - 07:24 am: |
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Brion nailed it. Too much mass with too much piston speed and the bottom of the rods explode.Its the same for any type of big bore long stroke motor. As already stated before Buell is limiting the rpms a bit to try to make the XBs the most reliable sport bike on the market (as per FUELL). Inline 4s use smaller pistons and shorter strokes and must turn more rpm to make the same power. Less mass allows more rpm but they need it. The current engine in the XBs is the best Ive seen so far to do what this bike was ment to do. The Sportster might be about 50 yrs old but the XB engine has been extensively modified from that. Anybody noticed how far back the roots of the Duck engine goes? The OHC inline 4s got here about 35 yrs ago and thats a while back too. Most of the XB engine is still simplistic so there is most likely alot more Buell can do with it. If you are wanting the power curve of an IL4 in a Buell you are not alone and I hope they start making them. But I prefer the type of bikes Buell has made so far for street use. In the 70s & 80s it was the IL4s for me and I made them hot too but Ive gotten tired of the long rpm curve with all the torque at the top in a narrow power band and not much anywhere else. The XB12s power band is almost its whole rpm range and its very strong and very flat. Thats also very impresive. Ive learned that the rpm range of the motor doesnt matter squat as long as you have enough torque and can gear it to run the speed range you want. The IL4s need 6speeds to keep you in the power band and they all have them. The Buell XB9s & 12s would be much more impressive with a lower primary or final drive to better use its torque and a taller 6th gear to give it a better speed range. Still this has got to be the best bike Ive ever owned and Im going to love riding it.
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S320002
| | Posted on Thursday, December 18, 2003 - 09:01 am: |
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"I am talking about a completely hydraulic valvetrain. You wouldn't even have cams as you know them. Just the Valves and a hydraulic pump running from the output shaft."
Who is using this in Formula 1? Would you explain how it works?
The other thing to keep in mind is that they are liquid cooled which is much more efficient than air.
??? Please explain how a "liquid cooled" system works without air.
I must be falling way behind on modern technology. |
M1combat
| | Posted on Thursday, December 18, 2003 - 11:48 pm: |
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Unibear... I'm not interested in putting an IL4 power curve in my XB. I like it the way it is. A LOT. This is the best motorcycle I have ever ridden (That's not really saying much but I have been on a Ducati 916, I hear they are pretty good in the grand scheme of things). I just think that by using fairly exotic technology the Buell race engines could be competitive. I see the point of making them reasonably close to the stock engine though, you can test and develop tech to use on the production line.
Again, for the record... I do NOT want an IL4 in my Buell. I like my torque plateau just the way it is. I like this engine for the same reason I like the 351C-2V in my Mach-1... The extremely usable power. I just think they should make a 351C-4V for the RACE bikes. I think a hydraulic (or even magnetic) valvetrain would be a fairly easy way to do it. I wouldn't know how to work on a damn hydraulic valvetrain so I wouldn't want one on my bike. |
M1combat
| | Posted on Friday, December 19, 2003 - 12:04 am: |
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S3 - Ford, Ferrari, Mercedes, Toyota and BMW are I THINK the teams that use hydraulic valvetrains (They also happen to be the ones who make the most power...). Others use magnetic and I don't think anyone still uses cams. I don't know how they work but I'll take a guess... Theres a hydraulic pump driven by "something" that has basically a cam system in it. That cam system moves pistons that move hydraulic fluid that travels along the hoses and into the head. Inside the head it actuates the valves. As I recall they run five valves per cylinder and ten cylinders. They run this system at above 18K but below 19K RPM shift points for a LONG time during test sessions. Engines very rarely let go because of the valve system. From what I hear it's generally broken rods or something literally melted. I think that a system like this to run a total of eight valves at 9K-10K RPM's would be fairly easy to make reliable... Also, F1 engines get MUCH warmer than our V2's do... |
Wyckedflesh
| | Posted on Friday, December 19, 2003 - 12:13 am: |
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The hydraulic valve systems also run much higher pressures and "instantaneous" open. The springs that assist the hydraulics in closing the valves are also a lot stiffer then on a cam set up. Now the actual method of operation is a bit fuzzy, Popular Mechanics did a breakdown and discussion article about them oh about 5 or 6 years ago. They also covered the magnetics which use alternating magnets to open and close the valves, as well as the cylindrical valve train which is basically a round "cam" with a shaped tunnel bored through it from one side to the other. As the tunnel openings match the carbside intake port and the cylinder side intake port the flow runs. Because it spins and doesn't work any springs or rockers or anything like that you gain HP from the lower parasitic drag of valvetrain operation. If you wanted a new cam profile you just CNC'd new tunnels. I think this one got scrapped though cause I haven't heard more about it, they were having sealing problems around the "cam lobe" on the cylinder side at higher compression ratios, since it basically sits where a normal valve seat goes in the head. |
M1combat
| | Posted on Friday, December 19, 2003 - 01:28 am: |
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Hmmm, I could be nuts (and probably am) but I could have sworn that I heard of a modern bike that uses the "rotary valve" system you referred to... I read it on this site too... Lemme do a search. |
Rocketman
| | Posted on Friday, December 19, 2003 - 02:43 am: |
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I think you guys are referring to engines that use pneumatic NOT hydraulic valve trains.
Anyway here's a well known pneumatic set up. Aprilia RS Cube GP engine
Rocket  |
Unibear12r
| | Posted on Friday, December 19, 2003 - 04:23 am: |
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My apologies M1, that was posted at a very insomnious 4:30AM my time. I wasnt quite lined up straight on the subject. I was just trying to say that I thought there was still a lot Buell can do with the XB engine. I was also trying to say that that the current Buells are aimed at a limited market and that eventually to expand Buell is most likely going to build bikes to compete against the IL4 zoomies. I think its GM who is working on electric valves that would be controlled by the engine management electronics. They plan to control engine RPM & power by valve timing, fuel injector timing and spark timing. A fly by wire engine! I owe you a beer if we ever meet. Mine will have to be something different as I am allergic to beer and peanuts. |
S320002
| | Posted on Friday, December 19, 2003 - 09:07 am: |
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...pneumatic set up...
Okay now we're getting somewhere. There are several F1 teams using pneumatic valve return "springs" but I have yet to see any of them use hydraulic valve actuation. The Aprilia design is technically not a pneumatic valve train but only a pneumatic valve return "spring" as in F1.
PM often prints articles on undeveloped concepts that never see the light of day.
M1,
You are probably thinking of the Brutale's radial valve setup. It was misquoted on this board as being a rotary valve system. Two entirely different designs.
I still would like to see that liquid cooling system that is more efficient than an air cooled system.
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S320002
| | Posted on Friday, December 19, 2003 - 09:11 am: |
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By the way, F1 engines still use cams. |
Wyckedflesh
| | Posted on Friday, December 19, 2003 - 09:38 am: |
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What liquid cooling looses in parasitic drag, it makes up for in sound deadening. And since the EPA is also getting stricter on the sound levels of the engine mechanicals its going to get harder to make an aircooled engine. (Epa measure the mechanical sound levels (valve train noise, piston noise gear noise ect), the intake sound level (how loud the sound of the intake is) and the exhaust sound level. Watercooling helps to cut down alot on the mechanical sound levels.
I totally forgot about the pnuematic systems. My bad. |
M1combat
| | Posted on Friday, December 19, 2003 - 10:58 am: |
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Hmmm, I was pretty sure that the teams I mentioned (with the exception of Toyota... I guessed on that one) were/are using a hydraulic valve actuation system. I watched an F1 tech show near the beginning of the 03 season that said the "top teams" are running hydraulic valve trains... I suppose it's entirely possible that I am wrong though  . |
M1combat
| | Posted on Friday, December 19, 2003 - 11:55 am: |
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LOL... I stand corrected... Just did a bit of research (which I probably should have done already...) and they do indeed use a pneumatic valve system. At least they did in 2001...
Ok, so ummm, never mind me... Forget this thread. |
Wyckedflesh
| | Posted on Friday, December 19, 2003 - 01:51 pm: |
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to late  |
M1combat
| | Posted on Friday, December 19, 2003 - 02:58 pm: |
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Well, I still think my hydraulic valve system is a good idea though... . |
Hootowl
| | Posted on Friday, December 19, 2003 - 03:09 pm: |
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Didn't the Barton engine use rotary valves?
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Rocketman
| | Posted on Friday, December 19, 2003 - 03:22 pm: |
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Hoot the Barton is 2 stroke - these guys are talking 4 stroke!
Rocket |
Blake
| | Posted on Friday, December 19, 2003 - 05:40 pm: |
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You might say that my '97 Cyclone has a hydraulic valve train.
Greg,
Thanks for keeping things real here.
I'd add one more thing... it's not the overhead cams that allow the IL4 valvetrains to withstand five digit revs, it is the much smaller/lighter valves comprising the four or five valve heads. Smaller valves mean a lot less mass to return to the valve seat.
I've heard that the pushrod side of the Buell valvetrain is not the governing factor affecting valve float; it's the big valves. The ratio of valve side to pushrod side rocker arm travel has a surprising effect too.
Question... If, for simplicity of debate's sake, the ratio were two to one (2:1), and the effective inertia of the valve side were half that of the pushrod side, which would govern the onset of valve float? Being that KE=1/2mV2...?
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S320002
| | Posted on Friday, December 19, 2003 - 10:24 pm: |
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"What liquid cooling looses in parasitic drag, it makes up for in sound deadening. And since the EPA is also getting stricter on the sound levels of the engine mechanicals its going to get harder to make an aircooled engine. (Epa measure the mechanical sound levels (valve train noise, piston noise gear noise ect), the intake sound level (how loud the sound of the intake is) and the exhaust sound level. Watercooling helps to cut down alot on the mechanical sound levels."
All road going engines are in fact air cooled. Some engines use liquid to transfer heat to a radiator where the liquid is then cooled by air.
Most people, including myself, refer to these liquid heat transfer systems a liquid cooling but that is a misnomer.
Many marine engines are truly liquid cooled because they have access to a practically unlimited supply of cooling liquid and can use it in a total loss liquid system.
Wyc,
You are right about liquid aiding in deadening some engine sounds but it isn't always enough.
The HD VR1000 race engine could not have passed noise emissions standards even with a near O db muffler due to the amount of "mechanical" noise it generated.
So far most manufacturers have gone with liquid heat transfer systems because they can cool hot spots by "overcooling" the rest of the engine. In reality it is not at all efficient.
Erik Buell thinks about these kinds of things all the time.
Blake,
You're welcome. I do what I can. I also like to keep 'em thinking.
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