R6 Exhausts & Mapping

[No_Style]

Hi All,

Looking to replace the Graves slip on that is on my R6, principally because it's cracked at the mounting point and also because it rubs on the swingarm. At the moment the bike is also pretty loud, so loud that I have a suspicion that one or more of the exhaust valves is not completely seating or sealing in the head. I'm going to have take the engine out of the frame, and i figure whilst I'm doing all this surgery I may as well look into exhaust options.

In theory the bike I have is making 117 HP (Peak @ 15,100) and 57Nm peak, with a pretty flat torque curve from ~11,000 to 14,800 rpm. That said, it doesn't feel like it, feels slower than the old 09 Daytona 675, which was both heavier and produced less peak power with taller gearing (better torque curve though)...

So, 1st question:
Compared to the current setup (stock headers + aftermarket midpipe & slip on), do you see any worthwhile power/torque gains (or changes in the shape of the torque curve) from a full race system?
Or,
Do you really only see substantial gains (10%+) if you go the whole hog and do the cams, intake work, velocity stacks and airbox mods etc?

2nd question:
Which places in a Sydney can remap the stock ECU on a dyno?
(seems like a cheaper and better option than a Bazzazz or PC5 interceptor with ignition timing modules etc).

I reckon I'll try and get a dyno pull done with an AFR reading and see what it tells me, see if it looks anything like the dyno map for this bike from 2010.

Cheers

[Marshy]

Whoa! I want your dyno! My stock racebike has 113 with a full Over Ti race exhaust, BMC air filter and Bazzaz. And it goes pretty hard, I reckon. A good R6 with stock headers + aftermarket mid-pipe and muffler is around 110. Hell, some even with a full system are around 110. The stock headers aren't terrible, and there's not usually a massive improvement with a full system. You can save a bit of weight though.

You only get really significant power gains from internals. The biggest improvement, bang-for-buck and reliability-wise, are slotted cam wheels (on stock cams). R6s have way too much overlap from the factory (and often the stock timing is quite a way out, apparently), and they greatly benefit from dialling out the overlap, with no downside at all - there's simply no adverse effect on the engine besides the extra ponies. This mod is probably an extra 8hp, give or take, all else being equal.

Then with all the major internal stuff, it seems it's only as good as its last refresh, cos the uber-trick, full-blown YEC supersport bike I just bought, with cams, valves, velocity stacks, thinner head gasket etc is frankly nothing special. I was very disappointed, and obviously need to get it on a dyno (and pull it apart for a look-see inside) to find out what's going on. I suspect it's not fuelled right, for a start, but I'm also sure that they need refreshing much more regularly than a stocker to maintain their performance.

Q2: Tuneboy

[No_Style]

Okay, so just to make sure I'm following you 100% here, you are talking about changing the timing of the intake cam relative to the exhaust cam by using an adjustable cam gear on the end of the camshaft (does it actually mature which camshaft the adjustable gear goes on to?). To be even more specific, you are saying it is in widening (increasing) the Lobe Seperation Angle that gives the gains. In that case, that's a relatively easy and cheap mod to do myself if I get a timing wheel and a dial gauge to calculate lobe centers (and a thousand hours to pull the engine out of the bike). Now my million dollar question, how much of an increase in LSA? (and/or what absolute number in terms of crankshaft degrees should one aim for?)

Is there much to be gained from different cam profiles? (i.e. changing valve opening and closing rates and durations etc, and just setting aside the fact that this would be a significantly more expensive mod).

On the intake side, what are most people doing, just replacing the filter with a higher flow element or are they actually changing/modifying the entire filter box?

[Stu23]

no way a std R6 makes 117 and that much torque !! 109 to 112 is the norm... dodgy dyno operators gotta lov em

With a good full system, dialled in cams, and a bit more comp will give you approx 118 from a fit fresh engine, and thats about as far as you can go without major internal mods.

Im having mine dynod on Monday to set up the fuelling as i ran out of time to get it done before the st george meeting.

My last motor was 119 at the wheel , built by the same chap who built my current one, I had this motor dynod on Trevors ( used to tune all lthe yammy supersport for the factory for a few years ) so know its a true reading

dyno's lol some are just too funny to believe

camshaft degreeing values are closely guarded secrets !! good luck with finding someone who builds proper engines to actually tell you !

oh and i flash R6 ECU's 06 to 12 i think i can do

p.s I am thinking of selling some R6 factory cams.. proper factory cams, not graves etc

[Marshy]

Okay, so just to make sure I'm following you 100% here, you are talking about changing the timing of the intake cam relative to the exhaust cam by using an adjustable cam gear on the end of the camshaft (does it actually mature which camshaft the adjustable gear goes on to?).

Yes, that's right. And you change both cam wheels; the one on each camshaft. You can buy them in a kit of two from various places (Graves is one). They are not that exxy either ($150ish, from memory, for the Graves). I've got some sitting at home, waiting for inspiration.

To be even more specific, you are saying it is in widening (increasing) the Lobe Seperation Angle that gives the gains. In that case, that's a relatively easy and cheap mod to do myself if I get a timing wheel and a dial gauge to calculate lobe centers (and a thousand hours to pull the engine out of the bike). Now my million dollar question, how much of an increase in LSA? (and/or what absolute number in terms of crankshaft degrees should one aim for?)

Fuck knows. That really is the million dollar question, and that's why my cam wheels are still sitting, unopened, on the bench in the workshop. Many, many hours googling has revealed a few choice details about OEM measurements, but still nowhere near enough to risk my engine.....

Is there much to be gained from different cam profiles? (i.e. changing valve opening and closing rates and durations etc, and just setting aside the fact that this would be a significantly more expensive mod).

Not as I understand it. Certainly not enough to justify all the additional expense (you need valve springs etc too) plus the higher wear rates and significantly higher failure risk. But I guess if you are after every last pony, then you'd do this too. I wouldn't bother for club racing.

On the intake side, what are most people doing, just replacing the filter with a higher flow element or are they actually changing/modifying the entire filter box?

AFAIK just changing the filter to an aftermarket one. That's certainly all I've heard about. Anyone else know any different?

[No_Style]

I agree on the dyno numbers. Unfortunately I can't attach the scan of it as it seems that the file size is too large (2.88 mb). Anyway, I know the absolute numbers produced from a dyno vary quite a bit from dyno to dyno, setup to setup and obviously with ambient conditions, so I don't have much faith in the numbers really unless they're back to runs looking for a relative change.

That said, the actual shape of the curve shown on the graph, does not seem to match what it feels like the bike is doing.

Edit: Just so we're clear here, I'm probably not going to do much more than fix the exhaust and maybe replace the filter element, I'm just a sucker for wasting time learning about things for which there is 99.95% chance that I will never put into practice...go figure
I understand why the LSA and timing stuff would be guarded, thats serious labour hours in pulling the engine out, apart and putting it all back together between dyno runs. Heck, even if you have an engine dyno it would still be annoying to change the timing, check clearances and then re-seal everything between pulls.
You could check the maximum limits of an increased LSA by taking it all the way to the minimum valve clearances, but without knowing what number to set it too, well you may as well leave it stock given how much it would cost you in time and dyno runs to work it out yourself...

[Marshy]

Oh, and a thinner head gasket is also a cheap, harmless mod. I've got a YEC one sitting on the bench next to the cam wheels......

I have no idea how much actual benefit they give. I've researched, but couldn't find an answer online either.

[Marshy]

Unfortunately I can't attach the scan of it as it seems that the file size is too large (2.88 mb).

Try again - I've increased the limits.

[No_Style]

Still saying its too large. Its a 2.88mb PDF file.

[Marshy]

Still saying its too large. Its a 2.88mb PDF file.

Sorry - turns out I can't convert bytes to megabytes in my head! Who the hell measures filesizes in bytes these days anyway?!?!?! Fixed (hopefully).

One more time for the dummies, if you please.

[No_Style]

No luck sorry, wonder if it doesn't like the PDF file format?

Bits:
https://www.google.com/webhp?complet....88+mb+to+bits
24159200

Bytes:
https://www.google.com/webhp?complet...88+mb+to+bytes
3019900

[Marshy]

In theory pdf should be fine, and I increased the limit to 5000000 bytes (ie 4.7MB). Buggered if I know....

Take a screen shot and upload a smaller jpg?

[No_Style]

Try this, hard to read due to being a screenshot of a scanned PDF, but anyway:
Dyno Run - As Bought.jpg

[Stu23]

you dont need to buy cam sprockets, the ones you have in your engine can be slotted Dialling them in allows you to move the power around, and make the best of what your engine can give, you wont get any more top end power out of it. Similarly increasing the compression with YEC or shaving the head will increase your mid range power quite a bit, and maybe bump the top end 1 or 2 bhp max. As marshy says, the stock headers are quite good when the cat is removed and a mid pipe is installed, after market will save you Kg's however and maybe 2 to 4 bhp tops

[No_Style]

Sounds good. My major aim is to try and fix the hole in the mid range. This bike really doesn't start to pull until an absolute minimum of 12,500 at the moment, it's totally leaden beneath that. The real power band seems to only be about 13,500 to 15,500 at the moment. I'd like to try and get it to pull harder from at least 10,000, preferably 9,000.

So it's sounding like slotting the cam sprockets and increasing compression with a thinner head gasket would be relatively cheap to have done or to do myself if (as I suspect), I'll be taking the head off anyway to fix the valve seating (assuming the compression test does indeed show that this could be a problem).

[Marshy]

Yep, it sounds like a maintenance/tuning problem. Also, bear in mind that 'the tuning lord giveth and the tuning lord taketh away' - as a general rule, when you add more 'maximum horsepower', it comes at the expense of midrange torque!! I can't tell you how many people I've known that have added full systems, dyno tuned etc (especially on road bikes) and have hated the result as the bike 'feels' waaaaay slower! A full system is the biggest contributor to this, and in many cases track day riders even prefer R6s with the collector/cat still in place, as all that back pressure gives a hell of a meaty midrange for corner-exit drive, and even more so on stock gearing, rather than having to rev the tits off it at the top of the rev range to get any power.

My stock-motor racebike is like that - it's punchier than the YEC bike and has more midrange, so feels faster. Dunno if the YEC has more top end yet, but it subjectively feels slower.

My most favouritestest R6 ever was my first one, the 09 which was otherwise stock except for APE cam wheels dialled in for meaty midrange. It pulled like a Mack truck from 9.5k and was still 118hp at the top.

[Stu23]

Agreed 100%..... i have mine built for mid range , well i kinda need it lol

[Mr.Ed]

So no one ported/polished anything? interesting... I was expecting some of that as it's recommended on the Kawi race manual although they do say to only polish it and even then it's VERY mild and not all the way.

[No_Style]

So given that I'm probably never going to be able to find the glorious LSA number, or safe minimum and maximum valve clearances or overlaps etc etc Who's a good shop in Sydney (even better if it's on the Northern Beaches) to talk about timing and basic head work to try and sort out the midrange?
It's sounding like I can just stick with the existing exhaust and stock headers (maybe replace slip on if need be, for non performance reasons), so that's a nice saving there.

[Mr.Ed]

If you're ever keen on a full system keep an eye on the WERA classifieds...some crazy bargains there every now and then. Saw a full Ti Graves go for $600 not too long ago.

[No_Style]

My general understanding is that 'polishing' is a bit of a misnomer. A degree of roughness on the intake walls actually helps reduce the overall thickness of the boundary air layer (i.e. a steeper air speed gradient when compared to distance from the intake wall, ala a wider and faster corridor of air coming in through the intake ports) than a highly polished mirror finish. Whilst that would seem counter intuitive, apparently it's true, though I've never been in a position to test it. But aerodynamics can definitely be pretty un-intuitive on some fronts. Velocity stacks actually aim to achieve a similar thing, namely to increase the size of uniform - laminar - airflow corridor and the airspeed in the intake (though velocity stacks are more specific, aiming to reducing the constriction in the 'choke point' near the start of the intake that exists due to air turbulence when shoved into a square cut pipe/tube opening). That said, by all accounts the factory intake is pretty darn good really, and aftermarket velocity stacks are seriously expensive, particularly against the improvement that they offer.

Similarly port sizing, bigger ports does not necessarily equal better flow, as it's also a function of the port length and shape.

Stuffing around with that stuff without proper flow testing and CFD modelling would be pretty misguided. Not to say you can't improve on factory stuff as they compromise on things for reasons of machining cost and production rate etc. It's more to say that if you are going to, it needs to be done properly, which implies seriously expensively.

[Stu23]

Ive been told the inlet ports on most 600's are too big , I know in the UK thye used to fill them in a bit and tidy them up. The exhausts im told they can work with making them smaller !!

Basically the engines today are very well designed and made, so no rough edges / casting / milling to make a massive difference , just a little tidying here and there

[Marshy]

Agreed re polishing. It's not really effective for bikes. Also the port sizing etc; it's the same as the exhaust discussion above - you can't have your cake and eat it too. Adding in one area generally takes away from another. OEM stuff attempts to get around this with variable inlet tracts, exhaust flapper valves etc.

[Mr.Ed]

Attack sells a 'modified' version of the v.stacks for the ZX6R for like $50 or thereabouts... but there's a catch. They'll only sell it to you if you buy the rest of their stuff. So yeah... that rules me out.

If do get to ride consistently eventually (**kneels down and prays**) I'll have to do the valve clearance thing which is supposed to be a bit of a PITA on the ZX6R... if that's the case I might just bite the bullet and go for a thinner head gasket but that's as much as I'm willing to push it to be honest. I'm miles and miles away from needing more power... I could use a bit more torque though even if to save me from my own mistakes.

[senator8]

Oh, and a thinner head gasket is also a cheap, harmless mod. I've got a YEC one sitting on the bench next to the cam wheels......

I have no idea how much actual benefit they give. I've researched, but couldn't find an answer online either.

Are you sure Nick? I found this info below on the internet, so it must be true!

[QUOTE=Baddie; Yes...and helps cook your engine and reduces engine life.

Doesn't the dirty german have enough Hp?.
Maybe time to buy Jap bike. [/QUOTE]

[No_Style]

I would doubt it would cause huge issues other than if you reduce the thickness enough that the static compression was sufficiently high to cause the engine to start detonating rather than burning, or perhaps enough that you needed to readjust the timing curve to account for the increased static compression and thus prevent pre-ignition or pre-detonation (pinging or knocking). But I don't know much about this stuff, so could be wrong. As speculation on Baddie's comment, it's also possible that it also causes a faster burn and generally higher cylinder temps, due to the more compressed AF mixture being hotter even before it's ignited, so maybe the stock piston head, sleeve or valves aren't designed/capable of dealing with that and various things start pitting. If there's any engine builders here, it would be interesting to know!

My understanding is that increasing static compression is generally a good thing (from a combustion efficiency point of view) and relatively harmless, but only up until the point that it starts causing detonation. I can see that manufacturers would allow a little headroom (no brilliant pun intended) in their design compression level for road bikes so that the engines don't start pinging on slightly sub par fuel or once even a little bit of carbon has built up creating the odd hot spot in the combustion chamber etc. With a well maintained (and relatively low km) race engine, you could capitalise on that lee way by skimming the head or using a thinner gasket to generate a bit more power pretty safely i would suspect.

[Marshy]

Are you sure Nick? I found this info below on the internet, so it must be true!

Nope, I'm NOT sure, but I've read a few really cool articles on how awesome raised compression is, so I'm just inferring from there (admittedly they were car engine articles).

I would doubt it would cause huge issues other than if you reduce the thickness enough that the static compression was sufficiently high to cause the engine to start detonating rather than burning

Actually the really, really big and immediate risk is fatally whacking the valve with the piston! There's very, very little clearance even at normal head height, and by lowering the gap it is ultra easy to run out of room. It's sure-fire way to completely lunch a motor.

I've read all the YEC manuals about calculating the appropriate head gasket thickness by making a putty and measuring 'squish' values and clearances etc, including some maths I've forgotten from high school, until it went into the 'too hard' basket along with the slotted cam wheels!

Actually, that's not quite true.... measuring the exact head gasket thickness was too hard, so I just ordered the most popular of the thinner sizes (and they come in point oh-five of a thou differences) and ordered that. Then I was gonna just risk the engine (rather than calculating squish values) and hope for the best, when I next (first) take the head off. Which was tentatively scheduled for sometime in this six-month break. Or the 12th (of Never)...

[No_Style]

Yep agreed, piston valves contact would definitely destroy it. I'm more going off Baddie's comment there, I'm assuming he's talking about some other sort of long term damage that I'm unaware of. Piston/valve contact which would be a pretty immediate sort of failure, more of show stopper, than just something that 'reduces engine life'.

[senator8]

Just for the record. I was taking the piss.

[No_Style]

Fark, that's twice now. I'm going to have to get to know the inside story on Baddie one of these days or it looks like this will keep happening

[Saturnalian]

p.s I am thinking of selling some R6 factory cams.. proper factory cams, not graves etc

Well i hope you attach the caveat to that sale Stu.

J.

[Saturnalian]

Just for the record. I was taking the piss.

Shouldn't you be asleep on the couch by now. It is after 1:00pm you know Rick.

[senator8]

Shouldn't you be asleep on the couch by now. It is after 1:00pm you know Rick.

Cruising bunnings with my 2yr old. Only laps I'm doing at the moment mate.

[chubb]

I want the power that all of you guys r6 are making.

Mine only makes 112hp on the dyno.

The week before St George.

Where is this magical 118 coming from??? What am I missing still???

[No_Style]

Probably a lying dyno

[Marshy]

I want the power that all of you guys r6 are making.

Mine only makes 112hp on the dyno.

The week before St George.

Where is this magical 118 coming from??? What am I missing still???

Hang on, my championship-winning bike is 113, and the new $$$$$$$$$ YEC bike feels LESS than that!! Plus you weigh 40kgs less than me, giving you roughly a 80hp advantage..... I reckon you're doing just fine!!

[chubb]

Yeah but I don't have as much riding experience as you do.

[Marshy]

You held me out for half a lap in the last race

And I was on my quick bike - the old one! PEPS.

[chubb]

Give me some credit. It was 3/4s of the lap!! You got round me at turn 9

:p

[Marshy]

Give me some credit. It was 3/4s of the lap!! You got round me at turn 9

:p

[Stu23]

yes rancell......... no extra power for you sir !!! just remember 1 bhp / 4 Kg's, so if you weigh 70kgs ( prob less ) and I weigh 90 kgs smack on, thats a 5 bhp difference... see how it equals out. and we wont go into braking hey

[Saturnalian]

I think we should now play.... How much does Chubb weigh ?!

[chubb]

73.8 the last time I weighed myself at the gym

[Stu23]

73.8 ?? No way... when was this had you just had a take away, or not gone to the loo in ages !!! more like 65 kgs me thinks

[Mr.Ed]

Dammit... it's almost a good thing I'm not riding then! How in the hell would I ever tip the scales with Chubb and I weighing nearly the same!?! Time for Little Mick's diet methinks.

[chubb]

Just put myself in the scales.

They don't lie!!

[Stu23]

Kelly.... get off rancells shoulders !!!

[senator8]

Just put myself in the scales.

They don't lie!!

Rigged!

I think you guys should try a hit of this http://www.combantrin.com.au/?gclid=...FUQRpAodqxsAxw

[Mr.Ed]

Oh well... I just need to lose 20 more kilos then.

20131115_091224.jpg

[Carl-52]

Mid range power is good!!!!! IF its all at the top end its unusable to everyone but those few special riders!!..... Increased Compression ratios normally give you an increase in torque over the entire curve, whilst also compressing that AF mix to maximise how much of it is burnt. Squish has a range of usefull measruements but they wont be felt unless the squich was outside this range to begin with and combustion chamber angles change how the burning fuel mixture flows around the combustion chamber and towards the Exhaust valve. Its true that you dont want a complete mirror finish on ports as the fine roughness helps keep the air flowing quicker and more uniformly... a port and polish normally means that they wil ensure that the inlet and exhaust tracts are perfectly flat with no ripples that could distort gas flow and create a vortex.