| Author | Message | ||
     Chuck |
since Buell motors have so many "short-comings", why don't "we" sketch out some of the things we'd like to see. Then some of the engineers among us could critique "our" designs. Who knows? maybe BADWEB could actually come up with a viable engine design that perhaps, one day, could be used in a proto-type, or even a production machine . . . . . . it could happen. Blake, think of all the "fun" you could have with your calculator  | ||
| Ralph |
Jmartz, uh, yeah, weaker. Okay, power wise, it is  But I'll stick with it also being an improvement. As far as the heads, hey, I've never said these guys were stupid. I don't doubt the engineers at Buell have found room for improvement in the heads, as well as many other places. All I'm saying is that the effort was mis-spent. Hell, I like to make armor. And darn it all, I do a pretty damn good job of it. I've even made a few bits out of titainium (that should make you happy Jose) and compared to the original its "better". Don't mean diddly 'cause its worthless in front of a bullet. Obsolete is obsolete. Chuck, you have to be more specific. Other wise GSXR 1000 will be mentioned. By the way Blake, you mention wanting a butt load of torque and how the way to get it is through these low turning V twin motors. Uh, the Hayabusa has more torque than any stock Buell and it is spread out over a much wider area, all the while being pretty darn flat in shape. Ninety-nine pounds buddy. For me, confined to a pushrod air cooled motor, Sputhe is the ••••. No way around it. That, all my friends, is why I'm so strongly disappointed with the new motor. There is nothing new in designing these motors. It's all been done. All you have to do is pick out the attributes you want and then figure out a way to package them so they work together. Instead of trying just a little innovation Buell has stuck with re-tweaking an unendingly tweaked motor. Sputhe took this type of motor to the logical end. All Buell had to do was borrow that set up and add four valve heads and it would have had...... a motor that still couldn't compete. But it would have come alot closer. bighairyralph | ||
| Loki |
BHR, I was not suggesting that about the single carb set-up. A dual carb set-up is all to easy to do. Just need to replicate what is on the race bikes. For the street I would probably drop down from dual forties to a dual 36 set-up. This way one should be able to increase the intake velocity and still feed both cyls. At the same time smaller dual intake valves would be a boon. Especially if you start to lift one just ahead of the other. The lead would help to keep the intial velocity up, close them both at the same time. But alas this would take an overhead cam motor to accomplish this small feat. Got a question for ya, have you had the opportunity to ride a Shadow VLX? This little 600cc v-twin is a little monster of a motor. The quip about the circle of evolution comes to bear with a rumor. If true or not I heard one of the big four was looking at an air/oil cooled v-2 powerplant. Loki plug difficulty relates to how much plastic one has to remove befroe one can even see the plugs. | ||
| Ralph |
Loki, I'm with you on the dual carbs. But lets face it, they still have to be synched and all that other stuff. For a street bike the single carb rules. I just have no common sense and really wanna do the dual dance Jose, those dual carb heads are easily available, all it takes in money. Heck, not much more than those titainium rods you're always talkin' about. Loki, the only thing I've ridden in years is Harley kinda stuff (Buells being the kinda). I'm way out of tune with ricey bikes. Hey, it's kinda funny. I just looked at the (lousy) photo of the Sputhe motor. The oil pump...look familiar? Crawl under your motor and take a look. bighairyralph i know you were talkin' 'bout plastic but it still don't take a dang'ed engineer to take all the crap off | ||
| Blake |
Ralph: Man, great topic eh? Look at all the interest you've initiated! It seems we are misfiring on one major point. Many of the issues you raise address inherent weaknesses of the HD 45 degree V-Twin related to achieving higher operational rev limits and to achieving "competitive" superbike type levels of performance. If that is what the designers/engineers are aiming for, then I agree, Buell chose the wrong engine configuration. I think you will agree however, that the performance goals for the Firebolt's engine were far from being those of a race ready storebought "superbike" a'la Duc 998, Mille R, GSXR750, YZFR7, RC51, or ZX750R. What I am saying is that the HD 45 degree V-Twin configuration is extremely well suited to the goals (simplicity, compactness, lots of low end torque, respectable power) of the Firebolt designer. Sputhe configuration?: I would strongly disagree that the simplicity of a single camshaft or the advantage of shorter pushrods outweighs having a red hot exhaust port right exactly where my knee rests. An offset pin crank could be cast as one piece. What precludes a using a one piece crank in the HD V-Twin engine? More later/tomorrow... Blake | ||
| Jmartz |
Ralph: About the Sputhe motor... Its 60 degrees allows for very large bores w/o piston to piston interference, plus it makes room for a vertically mounted fuel delivery. Having the cam in the center reduces motor width something HD has been increasing since the electric starting Panhead. Claimed power output is truly impressive. In trying to minimize costs and utilize most of the parts HD already makes, the left side of the motor is unchanged. Putting the alternator on the right for width balance ane using a belt primary would be things that might come in the future. Ti rods: After careful consideration I opted not to install these in my 1200 motor because I felt that the investmet would not justify the power ehancement. No actual power enhancement just quicker to redline and perhaps a bit more durability of the lower end. $1800 + rebalancing + incidentals, likely $2000 in the end seemed a bit much for releasing 5 HP at the top. Shumaker Heads: This is where I think $2500 + 2 smaller carbs (ca. $700) would make a good dollar to power response. 120 HP out of 1200 cc Sportster motor is a lot to be desired. I sure hope those guys that posted the S2 #'s were correct. Tilley machines (at least some iterations, are destroked (3.6) and overbored (3.75). Jose | ||
| Ralph |
Blake mah man, the exhaust on the Sputhe is further away from your leg than the tube of heat on your M2. There are less problems packaging the intake and exhaust systems on a 60 degree motor. More room. What I am saying is that the HD 45 degree V-Twin configuration is extremely well suited to the goals (simplicity, compactness, lots of low end torque, respectable power) of the Firebolt designer. Um, sure. So? How much more room would four valves per head take up? A single cam? How much more room, upkeep, mechanical aggravation would be added to use a less complex motor like the Sputhe? Zero, zilch, nada. I think the constraint on design of the new motor had more to do with manufacturing costs than performance. Which makes even less sense when you figure the old tech is paid for. When I look at the new motor, all I see is the old motor, tweaked. I guess that's just it, repackage the old tech, it's paid for. Blake, I'm way over my head here. I can't really give any type of informed opinion about the design of crank and fly wheel assembly. So I'll just back away, knowing that while I don't know what it is, there is a better way. I'll leave it to you, as an engineer, to prove to me, the uniformed heathen, why what's being used is the best. bighairyralph | ||
| Jim_M |
Ralph How about the Revolution engine? There's your 60 degree v twin. I'm hoping that this engine finds it's way into an X1.... | ||
| Blake |
BHR: the exhaust on the Sputhe is further away from your leg than the tube of heat on your M2. Maybe on a Sputh cruiser, but the rear header comes out of the cylinder well AFT of where the carb on my M2 sits. My right knee brushes a Force intake's elbow; that rear header on the Sputhe would broil the inside of my right knee/leg in no time. I suppose a heat shield could be tried. Howeve well it might run (we don't know) the dang thing sure cries out for some aesthetic enhancement. And that's another one of the positives for the HD 45 Twin; it looks so damn cool! That's impotent to lots of us ain't it? BTW, Buell is sure shipping up on the Duc air cooled twins. What does the Monster 900 put out? Like 70HP? It's OHC desmo valve train sure isn't limiting revs. I wonder if anyone ever tried berylium copper (stiffest metal known to man) or carbon fiber pushrods? CF ought to work great. Should cut the pushrod mass by at least half. I dunno Ralph, it seems that the Sputhe would suffer from the combined problems of pushrod and OHC valvetrains, without realizing the full advantages of either. You lose the hydraulic lifters, and gain a floppy cam chain/belt, that if it ever breaks, can end up toasting your entire engine. If you're gonna use a chain/belt driven cam, why not simply go all the way for a set of OHC's? | ||
| Ralph |
I've seen carbon fiber pushrods. The word was not "not so special". As Aaron has pointed out before that the valve side of the equation is more important than the pushrod side. Frankly, while that may be true, three ounces of pushrod is three ounces the valve spring has to push down. Regardless of what side of the rocker arm it's on. Sure, on one side it would act like four point five, but hey, on the other it's still three. c'mon aaron, jump me, i dare ya. i'll take all you engineers. see, got one arm tied behind my back Oh, and by the way, if you take a carbon fiber pushrod that weighs less than half of a steel one and then cut it half for a more effecient motor (Sputhe) it weighs half as much! Carbon fiber isn't the answer, it's only a material. The answer is (god forbid) engineers being let loose upon the world, unfetered by marketing hacks and only loosely reined in by budget. Blake my patient freind, I still don't think there would be any more fried leg with the Sputhe exhaust than with the Buell cooker. Even if there were a problem, please remember, I'm using this motor as an example of what Buell could have done, not as ah iron clad template. Sputhe was constrained by using stock Sportster heads, hence had little/no control over the exhaust packaging. Buell, with its engineering team, could have come up with a head designed for this particular set up and solved the (small) problems associated with it. I dunno Ralph, it seems that the Sputhe would suffer from the combined problems of pushrod and OHC valvetrains, without realizing the full advantages of either. You lose the hydraulic lifters, and gain a floppy cam chain/belt, that if it ever breaks, can end up toasting your entire engine. If you're gonna use a chain/belt driven cam, why not simply go all the way for a set of OHC's? Dude, you lost me. Sputhe uses hydrolic lifters, same as a Harley. The cam chain would be driving only one cam, unlike the current dual cam Harley. That would end up with less than half the engineering headache (you may have seen this setup in 'merican built motors for....say the last eighty years). Or, it could simply be gear driven. Probably not, even with a quarter of the gear you still have appreciable noise to contend with and lets face it, a chain that short is just plain cheap and easy. So what yer sayin' is one of the strengths of the 45 over the 60 degree V is the 45 just looks that much darn cooler? Dude, gimme a break Oh Blake baby, you finally hit the nail on the head though! Why not go to overhead cams, indeed! I've been using the Sputhe motor as an ideal if constrained to an air cooled, pushrod, V twin. I never said that is what Buell should have done. Only if they were set in that mold, what they could have emulated. Personally, I'd rather see Buell kick everybodys a s s with what ever it takes them to do it! I want people to look at Buells with admiration rather than amusment. I want people to see Buells tail ends ripping past them. I WANT BUELL INC TO MEET ERIK BUELLS ABILITIES!!! See ya bighairyralph hey, you guys all know you don't have to be an engineer to beat up on me, join in. its fun! | ||
| Aaron |
Nascar: 2+ hp per ci is state of the art Evo XL: 1.75 hp per ci is state of the art Sputhe = cut off V8, sure don't look like 60 degrees to me though AW (then again, XR750: 2+hp per ci) | ||
| Lsr_Bbs |
...hhmmmm Off the shelf 600cc repli-racer = 2.9 hp per ci 1000cc repli-racer = 2.6 hp per ci So, pushrod state of the art is where??? ....in the mirror it looks like. Neil Garretson X0.5 | ||
| Tripper |
Too-shay | ||
| Blake |
Carbon fiber isn't the answer, it's only a material. The answer is (god forbid) engineers being let loose upon the world, unfetered by marketing hacks and only loosely reigned in by budget. My point about the CF pushrods was that IF their mass ever became a performance constraining factor, simplistic and cost effective solutions are available far short of a major redesign of the entire valvetrain. Which is easier? Which solution would make more sense from a "use what you know works" philosophy? If valve train inertia is "the problem" then a lighter/stiffer material is dang sure a dang good "answer". Let the budgets fly and the engineers rule eh? Careful for what you wish big fella! You'll end up with a friggin' GSXR1000 sprouting between your legs. More than a great "engineer", Erik Buell is a SPECTACULAR "designer", a gifted architect of innovative motorcyles. With the pushrods between the cylinders, I can't imagine a reasonable way to get the rear exhaust port/header away from one of my knees. I really do think that this would be a show stopper for the Sputhe as applied to a Buell. Sputhe uses hydrolic lifters, same as a Harley. My bad. So plumbing oil lines halfway up the Sputhe cylinders to feed hydraulic lifters is "simple"? C'mon el grande furry one. That's a freaking nightmare of cluge all stuffed in between the cylinders. The Buell version is CLEAN, SIMPLE, and nicely packaged integrally to the crankase. The cam chain would be driving only one cam, unlike the current dual cam Harley. That would end up with less than half the engineering headache (you may have seen this setup in 'merican built motors for....say the last eighty years). Or, it could simply be gear driven. Probably not, even with a quarter of the gear you still have appreciable noise to contend with and lets face it, a chain that short is just plain cheap and easy. Actually, upon closer scrutiny it becomes obvious that the Sputhe Valve train is structurally inferior to the Buell configuration and is thus significantly more susceptible to vibration induced perturbations. The Sputhe cam drive chain would be VERY susceptible to a wide range of vibration like a guitar string reacting to it's resonant frequencies. The effects at speed (effectively distorting the desired valve actuation cycle) can be very bad and very challenging to combat. Every wonder why Duc uses a belt to drive their cams? Belts are generally accepted as inferior to chains for such an application (belt = stretchy/inefficient, chain = stiff/efficient). Likewise chains are generally accepted as inferior to gears (gear = stiffer/one piece, chain= stretchy/many pieces). Similarly, the stiffness of the Sputhe cam assy's structural foundation is inferior to the extremely robust/rigid Buell configuration. Significant vibrations/deformations would be likely to manifest in the Sputhe cam assy and it's supporting structure. Such vibrations/deformations would distort the desired valve actuation cycle (vibration/distortion will cause cams to vibrate/move wrt rocker arms). And perhaps most significantly, as the cylinders/heads vibrate fore and aft about their base (as they are known to do), the Sputhe pushrods, being significantly offset fore/aft from the axis about which the cylinders vibrate, will contribute significant distortion to the desired valve actuation cycle. All the above may sound trivial , but I assure you it is anyting but. Sorry not a very easily read argument, that. I need a drawing to help show what I'm trying to convery in mere words. What I'm trying to say is that when the cylinder heads vibrate fore and aft as they will do, and the cam chain vibrates, and the cam assy's supporting structure distorts, the valves' actuation can be detrimentally affected. The Buell configuration is WAY superior for combating/negating these valve train gremlins. So what yer sayin' is one of the strengths of the 45 over the 60 degree V is the 45 just looks that much darn cooler? Hell yes! Especially in reference to that ugly ass Sputhe engine! The character and artistry of a motorcycle is VERY important to me. I hate the duc Monster S4; it's UGLY engine/radiator and pitifully lacking integration of wiring/tubing is an abortion and an insult to Italian design. Again, be careful, you may soon find an RSV Mille sprouting between your legs. You don't care what a motorcycle looks like?  Not so large hairy Blake ain't buyin' that amigo!  Don't worry, I like you am very hopeful that Buell will hatch a bonafide superbike racer in the near future. I hope even more though, that I'll always be able to purchase a sister version with an easy breathing low revving, torque twisting, piece of artwork engine in the well recognized 45 degree common crankpin pushrod style... or something even more better...  Neil: Glad to see your username and pw are back to working for you. I was afraid you had dissappeared there for a while after your postulating that you had been banned. So, pushrod state of the art is where??? How about in the LeMans GTS class dominating Chevrolet friggin' Corvette!? Nyah!  Great Stuff! Blake | ||
| Anonymous |
The sputhe 60 degree motor uses 2 gears (4 if you count the one on the cam and the one on the gear shaft) to drive the cam. One is an idler and the other drives the oil pump. |
