That is an exceptionally smooth torque curve you have there CD, it must be lovely to ride.
I took mine for a nice long ride last night despite the rain, and with a little adjustment it feels much the same from 4k up now. only very small changes there, but when accelerating from 2k, it starts strong, but then a little weak spot from 3-3.5k. If I can smooth that out then I will be confident enough to get the exhaust chopped and be done with it.

 

Thank you sir....and it was nothing but pure luck that i got the right combination of parts and the near perfect map. Not bad for a free map is it? And don't forget....that flat torque curve is only there because of the EXUP valve. The 111.78 hp came from the gutted cat. No straight through pipe either...just the cat gutted and re welded back together.

 

Mr FLUX....this is from Wikepedia and it tells the definition of an EXUP valve.

Exhaust ultimate power valve

From Wikipedia, the free encyclopedia

(Redirected from EXUP)
Jump to: navigation, search
The exhaust ultimate power valve (EXUP) is a device fitted to selected

(FZR, YZF, XV1900, R series,MT-01) that constantly adjusts the back pressure within the collector of the exhaust system to enhance pressure wave formation as a function of engine speed. This ensures good low to mid-range performance.
At low engine speeds the wave pressure within the pipe network is low. A full oscillation of the

occurs before the exhaust valve is closed, and to increase low-speed torque, large amplitude exhaust pressure waves are artificially induced. This is achieved by partial closing of an internal valve within the exhaust - the EXUP valve - at the point where the four primary pipes from the cylinders join. This junction point essentially behaves as an artificial atmosphere. The alteration of the pressure at this point controls the behavior of reflected waves at this sudden increase in area discontinuity. Closing the valve increases the local pressure, inducing the formation of larger amplitude negative reflected expansion waves. A servo motor controlled by the

opens and shuts the valve. The EXUP valve operation goes from being almost fully closed at idle speed, through to being fully open at 9000 to 11000

Please note that no where in that definition does it says it's a device to decrease noise only. It's a device to increse TORQUE at lower RPM'S. :sifone:

 

And just in case...Mr Flux...ole buddy.....this link is from Yamaha Canada explaining what the EXUP valve is. After all Yamaha INVENTED the EXUP valve so i suppose they know why they invented it right?
http://www.yamaha-motor.ca/technology/technology.php?group=M&tech=EUP

Please note....NO WHERE in that explanation does it say that they invented the EXUP valve to decrease noise. They invented it to eliminate the "flat spot" that happens with a 4 into one exhaust system....and to increse torque at low RPM'S.

You want more? :smilielol5:

 

You want more? :smilielol5:

I'm still waiting for one single bit of information that specifically pertains to TRIUMPH Daytona 675 motorcycle engines, and NOT Yamaha designed engines.

Any time you're ready mate.

The rest of us are talking about Daytona 675's, y'know, this being a Daytona 675 forum and all, and you're here telling us all that we've got it all wrong despite entertaining your insistance that an outdated device on a completely different motorcycle engine has actual relevance to why Triumph chose to build a device that bears an implementational resemblance, but has been proven numerous times to have absolutely no functional resemblance to why Yamaha chose to implement it on some motor they built donkey's ages ago.

Triumph don't call it an EXUP valve either, so I don't know why you insist on calling it that. Triumph call it an EXBV, (EXhaust Butterfly Valve), so why do YOU insist on calling it an EXUP valve, and mistakenly ascribe the reasoning for Triumph's use of it as being the same as Yamaha's? To retain your argument perhaps?

Whenever you're ready to stop clutching at those straws and join the rest of us on the same page you're most welcome to do so. Hey, I've been wrong in the past too, hate admitting it, but I reckon I look less like a tool if I just come clean and say that what I once believed to be true across the board is now no longer relevant in a new and different modern application, rather than stubbornly hold onto outdated beliefs.

People used to believe the world was flat at one point too. No offence mate, but right now you're starting to act and behave with much the same fervour as the original round world denialists. I, for one, won't think less of you for discarding outdated beliefs.

 

The original design of EXUP is irrelivant. The question is for what pupose is it installed on the daytona? When there is clear evidence that the same torque can achieved with only mapping changes, it is obvious that it is for noise control. Why would Triumph spend time and money redeveloping the EXUP to achieve the same results? Because the likely alternative was a more restrictive muffler that would stifle peak power?

 

It might be interesting to show the stock exhaust system with a/f ratio & then do the same with the EXBV disabled. That would probably show the ratio being out & account for the variance in results of purely disabling the EXBV & not adjusting the map.

Or, I could be full of shit...

 

Great, now he's calling me a liar. <yawn> :smilielol5:

Canyondancer, your comments are barely worth responding to. But I will anyway! For one thing, I assure you the charts I posted were exactly as I said they were. A stock 675, stock header, TOR can. I guess I should have gotten a Notary Public here to witness the tests? The other charts people posted sure look similar in shape to my eyes, it is very obvious. Why is that? Probably because I have a thousand or more 675 dyno runs under my belt? Probably because they are all actually 675's?

Furthermore, you can't even read your own chart. 49-51T between 7-12k rpm? I printed it out, and a straightedge says otherwise. It is 40-50 or thereabouts, as it should be. Speaking of numbers, you seem to tout this magical "111.78" a lot. Do you realize your chart is reading in a STD correction factor? Which is about 2.6% higher than SAE. And, are you familiar with the concept of graph scaling? Your graph is scaled quite differently than mine, hence your dyno curves look flatter, and smoother. I always scale mine to be as BIG as possible, to enhance the view of any portions of the curves that differ from each other. Non sense in doing science if you can't make anything out of the results, right? And that was the whole point of this exercise, to see what the results said, objectively.

I'm starting to feel sorry I posted this thread, but if I hadn't, then the 99.99% of us who are objective and have a grasp of basic scientific method, wouldn't have gotten any info. I always welcome rational discussion of any results that I post. The key word being, of course, rational.

 

You know what's the best thing about beating yourself in the head with a hammer?

It feels so good when you stop...


I appreciate the posts too, J.D. Thanks for taking the time to share.

 

Whatever CD. People here have supplied evidence, spent their time, provided actual dyno runs, provided hard facts, and proved their point.

You've done nothing but wail and moan, and no matter how much people prove to you above and beyond all reasonable doubt, you then start insulting people and calling people liars simply because their facts don't fit your now proven-to-be-false beliefs.

You're acting like a little brat who sticks his fingers in his ears and says "I'm not listening, I'm not listening, You're all liars and you're all pathetic".

This now well beyond a joke and I think the only reason why anyone ever bothered entertaining your insanity up to this point was because they had some grudging respect for you, which has now evaporated.

I'm out.

 

Why is the EXUP on the daytona then if the same torque figures can be achieved with optimised mapping? Please just answer this question specifically without quoting Yamaha's design brief.

 

So, in fear of getting caught up in this battle, I'd like some advice. I've been having some issues with the exup valve, and want to either remove or disable it. I don't feel like spending the money on a fabricator to remove it for me (if I did, approximately what would it cost?) so I'm leaning toward leaving it open. If I disconnect the wire, how would I go about leaving the valve open 100% of the time?

Thanks,

Oh, and if I don't get a custom dyno tune done, would the dealer supplied Arrow tune do for the bike without the exup?

 

If you have a Tuneboy you can just turn it off. If not you can just cut the wires and the spring will hold it open. Either way the fueling will be a little off below about 6k. A fabricator can cut it out and replace with a bit of straight through for about £30-£60 UK but make sure they use stainless steel (sometimes called dairy tubing) and TIG weld it not MIG. Which ever way you go the torque loss isn't drastic and from 4k you would need a dyno to tell. Read through this entire thread for an informed desicion and you will see that with correct mapping nothing is lost (thanks Hordboy for putting in the work to prove this).

 

You sound as if you are clinging to any possibilities now CD. The adjsutment to the fuel map is not enough to foul the plugs (i have a 2t that runs much richer and still doesn't foul plugs). As for the cat, how much unburnt fuel is bunged down the exhaust at higher rpm (A lot more)? That is partly the job of the SAI to protect the cat i guess? If you remember, turning the valve of is a test for me before having the whole lot cut out anyway.

 

You sound as if you are clinging to any possibilities now CD.

He's certainly starting to sound desperate now. Following the usual pattern of concocting up whatever story, without actual emperical evidence, to justify his position. If I have anything to apologise for, it's for being so stupid as to waste my time even entertaining this madness.

 

I asked a wrench at work (C of G so knows his stuff), and he said it would take neat fuel on a hot cat to really damage it. Also, perhaps if I had opened the EXBV from day 1 I would not have suffered the progressive power loss, likely due to the EXBV's proximity to the cat, focusing a hot spot on the lower part. I commuted a lot last year so was in that rpm range most of the time.

 

I'm not holding my breath, but I'm still kinda waiting on an explanation on why it is he seems to be able to interpret the data I presented, while at the same time he can't interpret his own. Oh wait, I just answered the question... he's misinterpreted both! :duh: Nevermind.

 

So, in order to get the fuel mapping correct without the valve, I would need to buy a tune boy? Is there a less expensive way to remap it? A mapping from the dealer perhaps?

 

The dealer can only flash a map that has already been designed, such as the arrow or TOR. While the arrow has been designed without the EXBV, it was designed for the arrow full system so wont run right for anything else. You could get a Powercommander and a remap at any dynotuner but this obviously means buying the PC3 and getting it set up ($$$) and you will have a CEL which I think a dealer could get rid of for you. If you can find a dynotuner near you that has the Tuneboy software, then you only need to purchase the ECU unlock code for your bike to get it remapped but tuners using the TB software are still rare unfortunately. This would be the cheapest way I think if your lucky enough to find one though. Last option is buying the complete Tuneboy, (software, connection cable & unlock code) and trying to remap it yourself with the butt dyno (not easy as I'm finding out) and is a bit pricey, but you also have all of the fault diagnostics like the dealer tool, and can balance the throttle bodies etc.

If all you want is to get the bike remapped for the missing valve, then look for a tuner using TB. That's the cheapest option.
If you can't find a TB tuner then the PC tuner is the next cheapest.
If you do all your own maintenance then buying the TB might be appealing as you can save money not paying for services but then you must attempt to map the bike yourself, or take it to a dynotuner and convince them to map it with your TB which many won't want to do as it requires learning some new software, and they don't get to sell you a PC.

Hope this helps, and hope I got it all correct. Someone will surely correct me if I'm wrong about something! (and I will graciously conceed)

 

You are the one with the theory CD. Hordboy posted up facts, you have posted your opinion that seems to be based on yamaha's propaganda, and your calibrated butt dyno. Seriously how much proof will it take to make you change your mind?

Please bring some proof to the table this time.

 

Well said flux...

 

Conclusion

When I conducted this test I went into it as impartially as I could. Agenda? Not really. Yes, I had a suspicion on how it would turn out. I couldn't really help that, because over and over again, previously, I had seen results that implied it would turn out a certain way. Still, I wanted to be sure. I wanted to be sure I wasn't leading myself down a wrong path. I had an opportunity to do the test fairly scientifically, although admittedly it certainly isn't material for a doctoral thesis. Same bike, same dyno, minutes apart, maps in the ballpark, valve on, valve off. All I had to do was choose the map, hit "program," watch the blue bar scroll across to 100%, and make a run. The results were as posted. I clearly said, draw your own conclusions. I had already drawn mine from the data, and I will proceed with the information as I see fit. And so should you, dear reader.

Mods, I'd love to see this thread locked, because its really starting to circle the drain anyway.

 

I give in CD. You and your wikipedia quote, for a motor with completely different architecture are clearly right, and Hordboy with his dynographs for a Daytona are wrong. you have proved without a doubt, that if I remove my power wank valve and remap my bike, I will have a huge dip in the torque curve.I promise to leave it on there. I'm out.

 

You want to quote Yamaha CD?

From here

while Triumph's Daytona 675 nestles one in the secondary pipe, between the collector and the end-can, just after the catalytic converter. 'We didn't want the weight and bulk of the valve and its actuator at the back of the bike,' says Triumph's product manager, Simon Warbuton. 'This location is the best place for keeping the bike compact, putting mass where it will have the least impact on handling while still giving us the effect we wanted.'And the desired effect has changed. With advanced injection and ignition systems, the role of the throttle valve is no longer about filling the midrange or chasing horsepower. 'On the 675 it has nothing to do with emissions or peak power.' continues Simon. 'There's a small effect on torque at lower engine speeds and it can improve driveability in some conditions, but it really helps on noise - a valve in the secondary pipe helps to take the edge off exhaust noise without compromising power.'

So even a Yamaha site quotes Simon Warburton, the engineer who designed the 675, as saying that the EXBV on the 675 is not really about midrange torque at all, but rather all about noise.

Oh, but hey, what the f*ck would he know, eh?

I believe that this is otherwise known as "Check and Mate". :nod:

 

I'm back in! I have got to hear this. Perhaps Mr Warburton does not truly understand the purpose of the EXBV? After all, he didn't invent it did he. Poor Mr Warburton, I think he should've read wikipedia first.:itsok:.

 

it goes much deeper than that. the quote of Mr. Warburton was obviously fabricated by the Yamaha people in order to further their agenda. almost certainly, they want potential Triumph buyers to believe it's intent was only noise related so that they will think the Yamaha remains a superior performance product. unless Mr. Warburton himself either hand delivers the same quote to me in writing or sends it via certified mail, i will not believe that it is accurate or true.

i will continue to believe and worry that my bike, without the exbv, is down on torque compared to CD's under the critical conditions of 40-60% throttle below 7000rpm.

-mark

 

I thought she was dead but I guess not, heh. I was never aware of Warburton's quote or I probably never would have done the testing. :laugh: Well done.

CD is right, I am here to sell things. (Partially. The other part of the reason why I'm here is because I'm a 675 owner) I sell these:

If I have any "motivation" behind this thread, that would be it. Except, I sell very few and they're probably not even profitable, at the end of the day. So whatever. But thanks for giving me an opportunity to show it! :sifone:

I guess I have nothing further to add at this point.

 

Looking back through this thread, I think you owe Hordboy an apology CD. You as good as accused him of misleading members of this forum for his personal financial gain. I think if his motivation was to make money, it would be more profitable to stock and mail order branded performance items such as LV or Arrow. His motivations appear to be for the love of tuning, and seeing what he can get out of the 675. With the time and money he must have spent on developing his bike, it is unlikely that he would recoup enough money from the products that have come out of it, in a reasonable time frame, for it to be profit motivated. Not sound business sense.:crazy: