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Pamela O. Brown (Pammy)
| | Posted on Friday, November 03, 2000 - 05:58 pm: | 
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Jerome...I can speak for myself on this one...My bike wasn't an after-thought...as much time and effort went into the motor-building of my machine as that of the 'Weapon'. I have a modified head but stock valves. I have a 3and 13/16 bore and stock stroke. I have a balanced crank(and pistons) and S&S rods. I have a very non-stock andrews cam. I have an undercut tranny and an oil scraper in the crankcase. My bike is not anywhere near stock.
However...with Cycle-Rama heads, andrews cams and wiseco pistons(stock bore)and a Mikuni carb we have seen 110 rear wheel hp with no dyno-tuning.
I have been dyno-tuning bikes for many years and can assure you that my bike is as true as any you will see.
At Hal's Dyno-shootout in Wisconsin during Buell homecoming. My bike dyno'd at a little over 105hp and everybody's bike dyno'd low that weekend.(I am at sea-level here with 100% humidity)
So if you doubt my bikes ability....DON'T, It really doesn't matter what you believe. You are welcome to come here and see for yourself.
Thank You for your patience
Pammy |
Pamela O. Brown (Pammy)
| | Posted on Friday, November 03, 2000 - 06:13 pm: |
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you can go to cycle-rama.com and look at a couple of other Buell Dyno-charts.
Pammy |
Aaron Wilson (Aaron)
| | Posted on Friday, November 03, 2000 - 06:46 pm: |
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Pammy's bike is 87" single carbed, the Sundance bike is 75" dual carbed. That explains the similar power outputs.
AW |
Steve Madden (Smadd)
| | Posted on Friday, November 03, 2000 - 06:52 pm: |
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There ya go Jerome... getting Pammy all riled up! LOL Yes... we're discussing this like gentlemen (and women). But I always tend to be a bit sensitive when I think someone is questioning the Cycle-Rama wizards! Sorry.
As she says, her motor is far from stock. I tried to talk her out of dyno running the bike in Wisconsin... big difference in altitude, density, etc. But she ran it without any adjustments whatsoever. I didn't ride her bike while there. But mine sure ran like a slug! Down here, I crack the throttle and the front wheel responds. Up there... I felt like I was riding through mud! Next time I go to the Homecoming... I'll probably come prepared to change my own jetting. At least to get it closer.
Cycle-Rama have never even finished her motor! Still work and tuning to do on it but they're too busy with *paying* customers' bikes. And... they've gotta finish mine first! (Right, Pammy??!!) What really gets me about her bike, is that it's smoother and more tractable than a stocker!
I need to go back to that link and read more about the Sundance machinery. It's great to read about what can be done... and Sundance is doing some amazing things with their race bikes. As did Aaron Wilson and the Team Elves Bonneville bike. :-) |
Aaron Wilson (Aaron)
| | Posted on Friday, November 03, 2000 - 06:55 pm: |
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Re: Dynojet repeatability ... I'm sure Pammy can give more details, but the Dynojet compensates for atmospheric & temp differences, and comes up with a "correction factor" that's applied to the raw measurements. It even allows different formulas (SAE, DIN, etc). SAE is the widely accepted one.
In terms of repeatability, I've used roughly half a dozen of them and with one exception (the one at Hal's) I've seen amazing repeatability, even in vastly different weather. Also, I believe it was MCN that actually took a bike to several dynos in SoCal and compared the results and got very consistent answers from all of them (it's been awhile since I read that article).
Funny thing, at the '99 Homecoming the dyno at Hal's gave me an essentially identical reading to the one I use most often, my buddy Chuck's, which I had used a few weeks earlier. This year, it was down 6hp to Chuck's, which again I used just prior to the trip. Something happened over the course of the year, I think that dyno is messed up.
See ya,
AW |
Aaron Wilson (Aaron)
| | Posted on Friday, November 03, 2000 - 08:37 pm: |
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Geez Steve ... just saw that note. Thanks, I appreciate it, but I really must deflect the credit to where it's due: Ron Dickey and Joe George. I just assembled the bike, a trained monkey can do that. If I ever know a tenth of what they know, I'll die a happy man.
Having never met him, everything I've heard tells me Wes is of the same caliber, too. Can't wait to see your dyno sheets!
Someday when we're ready to retire the LSR bike I'll post it's dyno sheet here. It's a peaky sombitch, has no power at all until you wind it up and then it comes on like a light switch. Which works fine at Bonneville.
See ya,
AW |
Steve Madden (Smadd)
| | Posted on Friday, November 03, 2000 - 10:56 pm: |
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Well Aaron... I look at it this way too. What you did was what a lot of people just dream about and never do. Not necessarily LSR racing... but you know what I mean. Having a dream... and acting on it. The way all of you organized, obtained the resources, and put the whole thing together in a successful endeavor was *cool*! No question about it. As I know you've heard many times, the records were just icing on the cake.
One thing that's great about the Internet is that you read about (and sometimes meet) people that *do* things. Sundance... Nallins.... Team Elves... Rocket... Wes and Pam... Ron Dickey... Joe George... all people *doing* what they *want* to do and with so much to offer.
Sheesh... what got me started?! I'll get off the soapbox now. LOL
Steve
P.S. Having a motor built up by Wes is something I've wanted to have done for *many* years. I guess I'm just a little slow. But the Buell is the right bike... and this is the right time! I can't wait till the bike is broken in and tuned. Although it's going to be a "mild" upgrade (I put a lot of miles on my *one* Buell! LOL), I've been forewarned that it'll still be noticably more powerful than my stocker was. But we won't publish runs done on the dyno at Hal's! LOL |
Sean Pepper (Rocketman)
| | Posted on Friday, November 03, 2000 - 11:33 pm: |
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Seeing as how we have knocked my numbers around all week, I'm now gonna speak out of turn !
In the UK, there is a large contingent of people, me included, who doubt the readings obtained on American dyno's.
Maybe this has something to do with the British climate. In the States, you have so many varied climates, unlike us , and then you have so many dyno tuners, it's hard to tell\compare whos dyno is most accurate, and who's a competent operator.
117 RWHP from a Buell, and not tuned on a dyno as if to suggest there's more HP to come, in my opinion, is to be taken with a pinch of salt ! However, I would not be rude enough to suggest someone else's dyno figures are subject to debate, like mine were !
Incidentally, the Sundance racer has some special heads designed by some geezer called Dick O'Brien ! Maybe that's why it's down on power !
Anyway, I got a laugh out of that one. Seems me and Takehiro Shibazaki are the only folks on the planet using Dick O'Briens finest. Maybe this is the best kept secret in the power world, and the source of Rocket's freight train like power and very tractable, blindingly fast, S1W Hooligan.
At least I know I made the correct choice. Shame for you guys, he's retired now :~)
Rocket in England |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 01:44 am: |
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Rocket, I am not trying to rain on your parade here...this is the dyno page and that was my dyno chart. I don't have a stock motor so I should have a lot of power. I can't get into the "whose dick is bigger" fight with you guys for obvious reasons and it really makes no difference who thinks my runs are not true...although half the board was at Hal's at homecoming when someone else ran my bike on the old rickety dyno they had there.
I applaude you for getting out on the track and giving the guys "what for". Frankly that is not for me...It would scare the bejesus out of me to have to launch my torque beast from a dead stop in front of God and everybody.
But that is neither here or there....as I said, this IS a dyno topic and I followed the rules.
P.S. as far as I know...there isn't a machine in existence that 'measures' horse power. The equation is calculated off of torque....so if you go back and look at my torque figures on my chart...I don't know how I can cheat on that....That's just spinnin' the drum, baby!
Pammy... |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 01:47 am: |
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Oh, by the way, do you Brits use British dyno's?
Pammy |
Jerome Chappellaz (Jerome)
| | Posted on Saturday, November 04, 2000 - 04:21 am: |
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Again Pammy, I don't doubt that lot of work was put in the development of your special X1 and that it's very powerful. I just want to highlight the usefulness of contests like Hal's Dyno-shootout in Wisconsin, where one compare apple with apple on the same dyno under identical conditions. When one compares "absolute" max power numbers, necessarily the question of accuracy of the measurement comes to mind.
Let's put it another way maybe. Here is what Reg Kittrelle at Battle2Win wrote in the volume 3 issue 3 this year : "Truly accurate, absolute dyno numbers can only be achieved under the most stringent of conditions. Conditions that the majority of dyno installations, ours included, cannot, or do not, meet. This does not invalidate their (our) findings, but it does require that they be viewed properly. Which means, relatively, not absolutely". And later in the article : "...However, by doing the testing on the ... same day / same dyno / same operator, any errors we commit remain consistent, making the relative numbers more valid."
Hoping that I do not make any offense or feel rude by reproducing these sentences on the dyno chart forum...
By the way, it is said on Steve's link to the Sundance Harley that it now produces 129 RWHP... It is not said if that number was obtained by the same guy on the same dyno as when they obtained 121 RWHP... ;-) |
Steve Madden (Smadd)
| | Posted on Saturday, November 04, 2000 - 07:11 am: |
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Jerome... Reg kitrelle wrote that... yes. (No offense Reg)But who is Reg in the world of Dynos and Dyno operation? Ya know... just because someone wrote it in a magazine.. doesn't mean it's the gospel. Has he been to Dyno school as Dyno owners and operators are required to attend? How long as he operated Dynos?
I'd refer to Aaron's 6:55 p.m. (Friday) post regarding repeatability. You too Rocket. And I'd defer my opinions to those who have successfully owned and operated Dynos for many years. People who are *seriously* in the business of building motors *cannot* be running Dynos off the mark. No way! They build customer's bikes to win... and in many cases, these bikes must meet stringent horsepower requirements (as in the case of the Buell Lightning Series).
Rocket's bike must be strong... but are his or other's Dyno results inaccurate? There are many other variables to running good times. Rider size and ability is a big one that comes to mind.
Steve |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 09:11 am: |
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There is a Crane ad in some of the popular Harley mags that features Wes(of Cycle-Rama) in it. In the ad it clearly states the HP of an 80 cu that Wes built as 124 rwhp. That was at the HP shoot out in Daytona(that's a Super-Flow Dyno which inherently reads less than Dyno-jet)...not on our Dyno.By the way...at the dragstrip...this bike did 11.18 @ 121 mph. Street ready, that is. P.S. Wes is 6'3" and weighs in excess of 200 lbs.
The other bike in the ad is also a customer of Cycle-Rama...'The Killer Dresser'(some may have seen this bike in Bandit clutch ads doing a Monster wheelie). This bike puts out over 140 HP and runs in the 10's at the Drag strip....(also not a small man)
If you really want to see some fake #'s...go to Cycle-Rama.com and look at the 136 rwhp S-1.
Man we may not be good motor-builders/head-porters, but we ARE good at magic....
Pammy |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 09:21 am: |
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P.S. I hope no one was emasculated or otherwise harmed as a result of my last posts.....
Another thing....I am not talking hobby here...this is what we do all day, every day, for a living!
Ron...I know you are watching and gnashing your teeth...or probably laughing at(me) my being an easy target. |
Sean Pepper (Rocketman)
| | Posted on Saturday, November 04, 2000 - 10:06 am: |
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Ah, but Smaddy Babe, I err on the side of less RWHP. I belive that's what got me into this mess !
Frank Torqued about me been down on power, which I don't agree with at all. I agree, I could have more, and I'm sure the heads would give more just by running that bigger cam and carb, but then I might as well throw in the bigger jugs too ! Maybe then I might just get beyond 110 RWHP (on a British dyno ) and I'm sure my S1W would be very similar to Pammy's X1, but I doubt 117 RWHP. After all, look how much "input" is necessary to get from a suggested 86\90 RWHP (stock + Race Kit) to 100 RWHP (and yes I'm sceptical about 100 RWHP claims from folks who add a carb or just flow the heads ! ), so imagine what it takes to lift you above 110 RWHP, never mind 100.
Incidentally, John posted a chart from Jim Dye's turbo Buell, running 14lb's of boost. Note how that torque monster "only" makes 120 RWHP.
Aarons post you refer to is also not an acurate yardstick. Not to bash Aaron either, as I'm sure lots of us here regard his input to the board as based on factual findings and good old fashioned sweat and toil, but, the article Aaron quotes from states that the dyno's used were all in SoCal so I would expect that to level up at least one operating parameter.
Aaron also makes reference to the dyno used at 99 homecoming and this years homecoming, stating that he belives the dyno in question is "messed up" this year (based on Aaron's methodical analysis of dyno comparisson's). Funny how Aaron's Buell was down 6 HP and Pammy's was at 105 HP, which from Pammy's recorded findings is some 12 HP down. Now that isn't consistent with Aaron's findings, and for Pammy it is twice as much HP down than what Aaron was. Or are we to belive, not only was the dyno at this years homecoming "messed up" on the day, it was also "messed up" betwixt pulls too ?
Also, your reference to the Lightning Series, I also regard with a pinch of salt. Not often, does a Race Kit only, equipped S1 hit the 90 RWHP mark. More often, such Buell's are anywhere from high 70's to 86 RWHP, which I also belive is why the Series has a target RWHP of 90, so as it very rarely get's achieved, otherwise there would be too many disqualifications, which in turn would not make the series very popular. And I also doubt the motor tuners for Buell's competing in the series would target 90 RWHP as there dyno tuning cut off. Given that all dyno's cannot be exactly the same, this would be a dangerous level to aim for, especially since I recall one of the race winners in the 98 season I belive, dynoed at 90.01 after the race, and they disqualified him !
So, Smaddy, am I glad I only dynoed at 100.5 RWHP. My findings at least look accurate and I do have that 200lb rider doing an 11.25 ET to support my findings !
I'm glad I'm English, as a nation we don't tend to exaggerate !
Pammy, in answer to your question, the majority of dyno's in the UK are US manufactured Dynojet's !
However, your comment about spinning the drum is relative to the amount of gears used down the strip, which you don't agree with me on.
Torque is the twisting force measured and is at its peak when a motor runs out of air. What you attempt to do with a dyno is tune your motor to use the amount of torque available to where (RPM range) you best want to use it. Having said that, and this is the relevant part to drag racing, a motor can produce more HP beyond maximum torque. This happens if your RPM's are still increasing faster than your torque is falling. I'm sure you understand this perfectly well, and for those of you that don't , take a look at Peter's dyno chart posted here right at the top of the page. You can clearly see how Peter's M2 reaches maximum torque at about 4000 RPM but his peak HP is achieved at 6800 RPM. This is a good example of why hanging on in the gears might give you a faster ET than you would obtain if you were to be "slowed" down by gearshift's ! The same applies to spinning the drum, when peak torque is achieved, it is the rising RPM's that the drum "see's" to calculate HP.
And no, I'm not suggesting you cheated on your dyno pulls either, but maybe your operating skills are a little rusty !............. Just kidding babe, keep your hair on !
Rocket in England |
Aaron Wilson (Aaron)
| | Posted on Saturday, November 04, 2000 - 11:54 am: |
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Rocket, you sure like to make things up.
Frank didn't say you were down on power. He said that if you really have 170cfm at 10", you should be making far more than 100.5rwhp. He's absolutely right. And I showed you that using the recommended constant, your horsepower indicates around 150cfm, which is just about what all the good head porters get from those heads. It's obvious to all of us what's going on. All but one of us, that is.
When Pammy had her bike at Homecoming, it wasn't making 117hp back in Florida, it was making less (I don't remember the number but she told me). This is an incremental project they're working on. Pammy, myself, Frank, Kerry, and others ALL saw about the same error on that dyno versus what we were seeing back home. The dyno operator told me they're getting about the same amount of error, too. Apparently they run their race bike on that one and a trackside one.
It sounds like you don't believe a Dynojet can correct for environmental conditions. What is it about the Dynojet's SAE correction that you don't believe? Do you believe the dyno doesn't make the temp measurement correctly? The humidity? That there's an error in the math? Tell us just how much error, percentage wise, these dynos have from the environmental factors? Like I said, I've only used a half dozen or so of them, in various weather. I gave my observations, I'd like to hear yours.
Yeah, you're right, we all exagerrate our results. The technique I use most is to kick the drum in the same direction as the wheel as I'm gassing it to make the power look better. That's why my curves look so choppy!
See ya,
AW |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 12:02 pm: |
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Rocket...the only solution to this argument in which we seem to be embroiled, is for you to come over here so we can arm-wrestle.
Oh...by the way...I can give you detailed suggestions on how you can work on those Saabs. That IS what you do for a living, right? hhmmmm, guess what I do?
I know what kind of Dyno's you guys use over there, I was being sarcastic to your 'Yank' remark. You 'boys' just think I am stupid.... |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 12:09 pm: |
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Oh, Rocket, 'babe'...My hair is fully on...you can't rattle me that easily...I know of what I speak because that is what I do.....I have taught many men the fine art of tuning on a Dyno-Jet dynamometer.
You, my dear, however might be beyond help...That very large chip on your shoulder inhibits your vision, I fear........
Pammy
P.S. Aaron, you are right...and remember I did not pull my airbox off due to a little accident I had the day before.....You go man! |
BigHairyRalph (Ralph)
| | Posted on Saturday, November 04, 2000 - 12:36 pm: |
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Ah ha, now I know how you pull up those great numbers Aaron!! |
Paul Batts (Xlwp)
| | Posted on Saturday, November 04, 2000 - 01:34 pm: |
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I would very much like to see (as yet another yardstick) the results of Denish's formulas for HP from MPH or ET. Maybe throw in some altitude and weather info to make the comparison fair.
Pammy, what would you say the total weight of bike and rider are for Wes on the 11.18@121 run?
Rocket, what were the total bike and rider weights on the runs you've mentioned?
John or Pammy or anyone, could you offer some tips on preparing a bike for a dyno run to get the best results? Best tire pressures etc.
PB |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 01:52 pm: |
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PB the bike Wes ran is a '93 FXR (it isn't lightened) It even has floorboards on it. Wes weighs almost 220#. Don't tell him I told you.
As far as preparing for a dyno run, if you have specific questions....otherwise I could go on all day....Not that I talk a lot or anything.... |
Idzerda (Hans)
| | Posted on Saturday, November 04, 2000 - 02:34 pm: |
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As you can set up the Dyno for SAE or DIN numbers then of course also for BHP: British Horse Power.
Highest numbers for a given engine are SAE numbers, lowest for DIN and in between for BHP.
SAE is the (reckoned) HP for the engine at the crank, DIN is the HP number what is left over after decreasing the SAE number with the (ESTIMATED) values for losses in the tranny, the dynamo, the ventilator, the oil pump, the pump for cooling liquid. BHP is somewhere in between.
So better believe me on this and Rocketman, you can make an end then on your bad humour.
Or is it all that water downstreaming in England, more than ever in 4 centuries, what makes you ill tempered?
BTW, do you read your email ?
Hans. |
Sean Pepper (Rocketman)
| | Posted on Saturday, November 04, 2000 - 03:53 pm: |
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Fact is, anyone can play with the numbers, and if you all care to re-read my post's you will see very clearly how I played with the numbers to suit my supposed flows and HP's; just the same way you guys 'n' girl did.
I attempted to show how my cfm's could easily have been calculated at 10" rather than 12", that's all ! What I wasn't expecting was a f**king lecture from you guys, especially since I don't need one.
Anyway, what difference does it make to you guys if it was 12", it's not the end of the world you know, or are you just affraid that some limey arsehole has a better flowing set of heads than you guys can belive !
The fact still remains, my motor has run an 11.25 ET and that tells me, there is a lot more in there, still to come.
You would all do well to brush up on your understanding of British humour, especially you Pammy, then perhaps you'd all be able to read between the lines a little easier, and maybe then, you'd laugh some.
Ah but I fear this isn't possible because you all take the horsepower game far to serious !
Rocket in England, off to dress up in drag and lick his wounds ! |
Jerome Chappellaz (Jerome)
| | Posted on Saturday, November 04, 2000 - 04:12 pm: |
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Hmmm, looks like Netiquette starts to be in trouble... Should it always be the case when we speak about POWER ?! :-))
For those who follow the current "discussion" and who may wonder why some (like me) bring the question on how accurate is a dyno reading and how accurate is the comparison between dyno readings, I recommend the following url, with some explanations about dyno source of errors, and this comes from a dyno manufacturer...
http://www.depac.com/applications.htm
From what I read above, it looks like most people who bring dyno charts on the forum know exactly what they speak about, and this is good. So this link is probably useful for only a hand-full of people. |
Steve Madden (Smadd)
| | Posted on Saturday, November 04, 2000 - 04:53 pm: |
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Jerome says "Hmmm, looks like Netiquette starts to be in trouble... Should it always be the case when we speak about POWER ?! :-)) "
Well Jerome... you know what they say: "Power corrupts."
Actually... I don't think there's a problem here with "netiquette". It's just a "lively" discussion... right? But the arm wrestling might be fun. ;-)
Steve
P.S. That article is too long... please just give me a synopsis of it. LOL |
Ron Dickey (Axtell)
| | Posted on Saturday, November 04, 2000 - 05:09 pm: |
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I chose Depac for the instrumentation when we set up our dyno. When you go this way you will be forced into learning more than you care to.
If I read the above post right I have to politely disagree---I dont think most people understand "power" at all. Not understanding "power" makes it nearly impossible to make the right decisions to enhance it.
I CAN tell you that the good people @ Cycle-rama are the REAL DEAL. |
Paul Batts (Xlwp)
| | Posted on Saturday, November 04, 2000 - 05:33 pm: |
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Pammy, maybe just some general stuff, I don't have any specific questions. I'm gonna' put the "W" on a dyno in a couple weeks and I want it to do the best it can.
Thanks
PB |
Pamela O. Brown (Pammy)
| | Posted on Saturday, November 04, 2000 - 06:32 pm: |
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Rocket you are very wrong...I have been laughing the whole time...I don't feel offended in the least. I can take as well as I give...makes life interesting.
Read between my lines, Don't underestimate me, it can only lead to embarassment. I am trying to be one o' the blokes (with boobs). I am not so fragile that I can't take some ribbing, but I am also not so tender that I can't give the shite back!
And Ron, where the heck have you been?! I heard you were coming down here for a week...he he he
I put the Supertrapp IDS on today and am only making 114.9 hp as of today. Maybe I will do some tuning next week if time allows. I have a certain someones bike in my care and he wouldn't be happy if he were neglected at all.
Oh, well...today is my birthday and I am going to lie around and do absolutely nothing for the rest of the day.....So guys, don't get all roudy on my account. Rocket, if my brand of humor pi$$es you off, sorry...but like Don Henley sings "Get over it!"
ta ta...off to my comfy couch and my book...
Pammy |
Peter Moltmann (Peter)
| | Posted on Saturday, November 04, 2000 - 07:03 pm: |
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Hey Pammy.
Happy birthday to ya!
So, now that you're one of the boys and not worried about that women/age thing, how old are you?
PPiA
PS. I've met Rocket and I've been picturing him rolling around on the floor enjoying the wind-up that's being going on......... |
Barney Fife (Deputy)
| | Posted on Saturday, November 04, 2000 - 07:20 pm: |
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, |
Stephen Heller (Ocbueller)
| | Posted on Saturday, November 04, 2000 - 08:00 pm: |
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WARNING! Following info is not P.C.!
It's common knowledge that the best dyno to check a Buell on, in any country, is the Polish made HOGFORCESKI 3000. My S1 consistently measures out to somewhere between 65 and 165 horses. Operator need not be Polish or sober. |
Pamela O. Brown (Pammy)
| | Posted on Sunday, November 05, 2000 - 07:42 am: |
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I am a very Happy 20-19 as of 8pm on Sat.(that would be 273, in dog years) I know I leave myself open for a lot of jokes on that one....
Pammy |
Steve Madden (Smadd)
| | Posted on Sunday, November 05, 2000 - 08:35 am: |
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20-19... that would be one year old! I didn't think you were *nearly* that old! I won't touch the "dog years" comment... at least not while you have my bike!!
Happy Birthday Pammy!
Steve |
Steve Madden (Smadd)
| | Posted on Sunday, November 05, 2000 - 08:36 am: |
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20-19... that would be one year old! I didn't think you were *nearly* that old! I won't touch the "dog years" comment... at least not while you have my bike!!
Happy Birthday Pammy!
Steve |
Steve Madden (Smadd)
| | Posted on Sunday, November 05, 2000 - 08:38 am: |
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Whoops! Well... have a doubly Happy Birthday!! |
Aaron Wilson (Aaron)
| | Posted on Sunday, November 05, 2000 - 09:56 am: |
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Happy Birthday Pammy!!!
Ron: Alright, I'm intrigued by your statement, and I'm not proud, I'll take the bait ...
Power is work with a time factor, i.e. instead of saying "I can move x pounds y feet", you say "I can move x pounds y feet in z seconds". RPM has a time factor in it, and therefore power is torque and rpm. Much as I hate to admit it, I think Rocket got it right, power is torque at high rpm. The formula hp=(torque*rpm)/5252 supports that.
So to make power, I would think you need to look at why your torque falls off at high rpm. What's constraining the motor and making it lose torque as you wind it up?
Am I getting close?
I'll step into it some more, what the hell ... let's assume the ignition and valvetrain aren't constraining the rpm ...
For a given stroke (mechanical advantage on the crank), torque is all about cylinder pressure. The thing constraining cylinder pressure at high rpm is generally the ability to continue to get a good cylinder fill as things start happening faster. And of course, that involves a complex relationship between port size and shape, valve size, cam lift and timing, wave travel in the intake and exhaust, bore size, etc etc. And of course, optimizing these things and making the trade-offs between them is where different folks' theories and ideas start competing with each other.
I'll tell you what, as much as I admire Denish, I don't particularly like that formula relating flow to hp. I think it's too simplistic. Low lift flow has a huge effect on hp, too. It's a key ingredient in the exhaust system's ability to yank on the carb before the piston does and give it a head start and more cylinder fill. As you well know, getting this right was worth a BUNCH of power on the race bike, we could not have set the records without it. Remember what happened when I did something that shrouded the valves at low lift? It certainly wasn't horsepower.
Now I'll go back and challenge the original question. That race motor has reasonable power, but since everything we did was toward that goal, it has no bottom end power at all. The thing is dead as a doornail until 5000rpm and then comes on like a light switch. It's not something I'd want in a streetbike (well, maybe with a 6-speed). So, all this time we've been looking for a higher power, and I submit what most folks really want is a high torque over a usable range.
Okay, embarass me, I don't mind ;-) ...
See ya,
AW |
Sean Pepper (Rocketman)
| | Posted on Sunday, November 05, 2000 - 11:16 am: |
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Aaron, it's old hat now, but having just read your post I'm curious to know whos "recommended" constant you're refering too, especially since I gave my reasons for the constant I used.
With regards to Frank, I agree with him to a point, but in his initial postings I mistook what he was saying and consequently, I assumed he was doubting what I had said. I tried to explain my findings and then expressed my wanting to end the topic, seeing as it was my motor and my engineering intelligence that was been brought to question.
However, when other folks jumped in on the subject, you included, I felt it necessary to defend my position, and at the end of the day, we have embroiled ourselves in dyno debates, when really, the subject matter is wether my heads were flowed at 10" or 12", that's all !
Despite what dyno theories we subscribe too, I would have thought a person with your superior knowledge on the topic, would have a much more open mind on what some folks claim for RWHP. You know as well as I do, it is very easy to "doctor" the results of a dyno pull !
Just to go off topic slightly, and seeing as how you refered to an MCN article, I too remember reading in some mag or other, where the journo's had taken some new, stock model Japanese bikes to the dyno and found all the bikes to be a good few horsepower down on what the manufacturers claimed.
Now, on the subject of dyno's again, it isn't the percentage of error correction, more what the operator tells it, and thanks to Jerome, what the Depac link states too ! I do like the sound of the very last paragraph though, about US Atmospheric Standards, and that now raises another question, which J Standard do you guys use ?
Anyway, it wasn't so much as "exaggerate", more, how can we belive what you Yanks tell us when us outsiders hear 2 million of your countrymen belive they've been abducted by aliens !
Rocket in England, no aliens ! |
Daniel Dunn (Buelliedan)
| | Posted on Sunday, November 05, 2000 - 11:23 am: |
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Rocket,
You want to blast us Yanks for Alien abductions?? That's a good one considering that you Brits have the Crop Circle thing and the Loch Ness Monster!! J
Be careful Rocket, you are outnumbered!!
Dan |
Pamela O. Brown (Pammy)
| | Posted on Sunday, November 05, 2000 - 12:10 pm: |
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Rocket...why don't you just swim on over here and take your beating like a man?!!!
Pammy ;o) |
Mark De Giorgio (Mark_in_ireland)
| | Posted on Sunday, November 05, 2000 - 12:50 pm: |
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I think its the gullability of the majority of the States that might be the real issue, alien abductions etc spring to mind, but the classic was when the BBC broadcast the War of the Worlds on the BBC World Service that had most of America panicking as the Martians walked amongst our corn fields blasting us with their death rays before finding safe haven in Loch Ness!!
How we laughed....... |
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