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Suzuki finds loophole for VVT in MotGP!

jimp

Sport Tourer
MotoGP has a "no Variable Valve Timing” rule which states, “Variable valve timing and variable valve lift systems, driven by hydraulic and/or electric/electronic systems, are not permitted.”

Well, Suzuki has found a way around that rule for their new GSX-R1000 with a mechanical VVT system. It sort of reminds me of the mechanical variable belt system on snowmobiles and ATV's, just a lot simpler.

Check it out...
http://lanesplitter.jalopnik.com/suzukis-new-gsx-r1000-is-engineered-around-a-loophole-i-1751372078

Too late now for the FIM to change the rules for this year.  ;D
 
That's pretty cool!  I love when a perceived underdog competitor figures out something that others didn't think of or dismissed thinking it was illegal.  It's what makes racing so interesting to me.  "The Smokey Yunick" effect!  Suzuki had great handling performance last year an only struggled at tracks where HP and top speed were needed.  Let's hope that this gets them closer to the others.  They have the rider talent!

 
That article is odd.  A production motorcycle cannot be  a moto gp machine.  To qualify, the machines have to be prototypes, or non production. The gsxr 1000 will be  a production machine, and would never be allowed to compete. 

I think the author confused world superbike with moto gp.  It would be sort-of fair to say suzuki found a loophole there to be able to use vvt because they incorporated it into their production machine.



 
I think they are planning to use the variable valve timing in a production motorcycle and their MotoGP bike, not use the production bike for MotoGP.

I found it amusing that everyone in the comments was blown away by this awesome "new" invention.  We used almost the exact same mechanism as a speed governor on our genset engines at Onan starting in the 60's. 

It is a clever use of the technology however.
 
The article wasn't 'odd" other than the writers lack of in-depth knowledge and poor writing skills, which is typical of the Lanesplitter contributors (he essentially did a copy and paste from the Euro MCN piece without the in-depth stuff). So when you see a link to them, always do your own research.

Like a lot of things on modern bikes, the VVT tech was developed for the GSX-RR tested in a couple of 2014 MotoGP races and then campaigned in the 2015 season. That tech is supposedly going to trickle down to the street going production GSX-R1000 for 2016.
 
You know our concours 14, introduced in late 07, has quite a bit more sophisticated valve timing system than this one, right?

He writes as if Suzuki did this to exploit moto gp rules.  That does not work long term as the exploited rule gets modified if it becomes an issue.

He also fails to mention Honda and Yamaha have not closed a valve, with a spring, for several years.  They use air. 

So far Ive offered info and you guys should have said, SHUT UP! WHO cares, and stop being an idiot.

However, I hope its heading this direction.

Our bikes still get terrible millage, and dont run very clean.  Euro 4 emissions just might be the breaking point to where air injection and catalyetic converters wont cheat their way through emissions testing.  The vvt might be a look towards clean running engines vs clean testing.
 
Roland - please enlighten us. Explain why the VVT on the 14 is "more sophisticated" than the system on the MotoGP GSX-RR. Is it because it is newer tech? Hydraulic rather than mechanical? More complicated? Heavier? What, exactly, makes it more sophisticated?

You must not know much about racing, or the Suzuki company. Engineers and mechanics live for coming up with unique solutions to rules limitations. Get around them, bend them, break them with the hope the inspectors won't catch it, it's in their blood. And if the rules change, well, try something else.

And Suzuki is not a deep pocket company like Honda or Yamaha, they can't afford to spend big dollars on design and engineering without some sort of result. In this case, they developed their mechanical VVT in 2014 to help them become competitive with Honda's V4's and Yamaha's crossplane crank hoping to buy time knowing that other engine rule changes were in the works for 2015 and 2016, giving them a chance to be competitive while working on further engine development. And your premise that it was developed for the street bike and used in their GP bike is wrong, because the tech won't reach the street bike till this year, two years after it was developed for GP.

Now you appear to be some sort of "greeny" or enviro-mental wacko going on about emissions. We're not talking about the street bikes here, thank you very much. This is about racing, and fun. But to satisfy you, Euro 4 was implemented in 2005 and the C14 meets the specs. So why don't you go suck on your tailpipe, the emissions should be clean enough for you (ask and you shall receive)

:-[  ::)
 
freebird6 said:
Homologation.  My first introduction was an article on the BMW M1

True, for Superbike, but we're talking MotoGP - prototype machines.

The M1... wasn't that the plastic bodied, drop door two seater? Pretty cool car.
 
I wont respond to what you'd like me to suck on other than to say we can have some fun here if you wont get personal and attack me.    You brought up a poorly written article, not me. The personal attack is the result of  a person not quite knowing what they are talking about,  and its an easy and cheap way to respond.

As far as the c14 being more sophisticated, just look at it, then look at the suzuki, and report back. Heres a secret.  One is tied to a computer, and uses hydraulics. The other uses steel balls. 

As far as emissions , the euro 4, you can look here if you want to.  They called it "euro 4" so that was good enough for me.  I think you saw the automotive standards, on wikipedia, and went all in.

http://www.bennetts.co.uk/bikesocial/news-and-views/news/2012/2015/august/interpreting-the-new-motorbike-legislation---what-does-it-mean-for-you/#.Vpz51cs2jIU


Not one of my motorcycles is epa compliant. All have power commanders, pipes, ecu reflash, and any other go fast part I can find.  With that being said, if I could get 50mpg, I'd be all over it. Longer range. 

Actually, better fuel mileage would be  a great reason to use this in moto gp.  I'm sure you know this, but they have a fixed amount of fuel. A slight improvement in mileage, for them, would be  a big deal.

So far Suzuki has not said public ally their moto gp machine even has vvt. It might is the best answer you'll find.




JPavlis_CA said:
Roland - please enlighten us. Explain why the VVT on the 14 is "more sophisticated" than the system on the MotoGP GSX-RR. Is it because it is newer tech? Hydraulic rather than mechanical? More complicated? Heavier? What, exactly, makes it more sophisticated?

You must not know much about racing, or the Suzuki company. Engineers and mechanics live for coming up with unique solutions to rules limitations. Get around them, bend them, break them with the hope the inspectors won't catch it, it's in their blood. And if the rules change, well, try something else.

And Suzuki is not a deep pocket company like Honda or Yamaha, they can't afford to spend big dollars on design and engineering without some sort of result. In this case, they developed their mechanical VVT in 2014 to help them become competitive with Honda's V4's and Yamaha's crossplane crank hoping to buy time knowing that other engine rule changes were in the works for 2015 and 2016, giving them a chance to be competitive while working on further engine development. And your premise that it was developed for the street bike and used in their GP bike is wrong, because the tech won't reach the street bike till this year, two years after it was developed for GP.

Now you appear to be some sort of "greeny" or enviro-mental wacko going on about emissions. We're not talking about the street bikes here, thank you very much. This is about racing, and fun. But to satisfy you, Euro 4 was implemented in 2005 and the C14 meets the specs. So why don't you go suck on your tailpipe, the emissions should be clean enough for you (ask and you shall receive)

:-[  ::)
 
I'd say so Steve.  Did a bit of digging around everyone seems to believe it does.  For instance:

http://www.motorcycledaily.com/2015/11/suzuki-displays-not-quite-a-concept-gsx-r1000-in-milan/


"Steel balls are positioned in grooves in the intake cam sprocket and adjacent guide plate. When moved outward by centrifugal force, they stack in different grooves during low and high RPM. During high RPM operation the system rotates the intake cam, retarding intake cam timing which elevates peak power. During low RPM operation, the camshaft returns to the prior position. VVTS optimizes intake valve timing is for both high-RPM, and low and mid-RPM ranges. So extra top-end power is available, without dropping low-to-mid range output."
 
I always thought retarding the intake cam; closed the intake valve sooner and resulted in more power at lower rpm's. But according to these articles (and about 10 others I just read), it seems that retarding the cam does indeed increase high rpm power. I did read at least 2 articles written by seemingly intelligent people that also had it backwards.

As long as its know that closing the intake sooner in the cycle is better for low rpm power, it doesn't matter what it's called. That's my story and I'm sticking to it, for now.
 
The online magazines are quoting from the Suzuki Nov 2015 Press Release for what Suzuki is calling the 2017 GSX-R1000 Concept (the plan for the production bike, but there might be some changes based on manufacturing costs or legal). From the Press Release, the key engine features developed for the new street Gixxer are from the MotoGP bike:

To achieve the engine design target of “Increasing top-end power without losing low-to-mid range output”, MotoGP derived technologies are combined into the new GSX-R power plant, resulting in the “Broad Power System”.

The combination of Suzuki Racing VVT (SR-VVT), Suzuki Racing Finger follower valve train, Suzuki Exhaust Tuning-Alpha (SET-A) and Suzuki Top Feed Injector (S-TFI) systems form the Broad Power System designed to increase high-rpm performance and top speed without detracting from lower-rpm and mid-range performance. The result is strong, linear power and enhanced acceleration throughout the RPM range.

•Suzuki Racing VVT (Variable Valve Timing System) ◦Steel balls are positioned in grooves in the intake cam sprocket and adjacent guide plate. When moved outward by centrifugal force, they stack in different grooves during low and high RPM. During high RPM operation the system rotates the intake cam, retarding intake cam timing which elevates peak power. During low RPM operation, the camshaft returns to the prior position.  VVTS optimizes intake valve timing is for both high-RPM, and low and mid-RPM ranges. So extra top-end power is available, without dropping low-to-mid range output.

•Suzuki Racing Finger Follower Valve Train ◦The new GSX-R1000 Concept’s valve train system is transformed from previous model’s bucket-tappet system to a finger follower rocker arm type to improve valve control and allow higher RPM. The reduced moving mass also allows increased valve lift and higher peak RPM, increasing peak output. Valve response and control is also enhanced throughout the rev range.

•Suzuki Top Feed Injector (S-TFI) ◦Secondary injectors located in the top of the air box operate at higher RPM to deliver finely atomized fuel through the throttle bodies and into the combustion chamber. The dual-injector design produces greater top end power without detracting from low-mid RPM range output.

•Suzuki Exhaust Tuning-Alpha (SET-A) ◦Suzuki engineers added two servo-operated SET-A butterfly valves, one in each header balance tube. The SET-A valve in each header balance tube remains closed to enhance lower-RPM and mid-range power, then opens to add significant power at higher RPMs.


It's not clear if these last two will be used on the MotoGP bike, or just the street Gixxer.

And Roland, maybe you shouldn't have started nuttin, then there'd be nuttin. I refer you back to your post on the 16th.

If you think having computer controlled hydraulics is "more sophisticated," think again. Many times something elegant and simple is more sophisticated. Modern complexity isn't necessarily more sophisticated.
 
What did I start?  We discussed what you posted.    No, I did not think you personally wrote it.

You took offense to my criticism of something you did not write, and wanted no part of the truth. 


When you say, "If you think having computer controlled hydraulics is "more sophisticated," think again. Many times something elegant and simple is more sophisticated. Modern complexity isn't necessarily more sophisticated."

Look up the meaning of "sophisticated" and you'll see it does not fit with what you posted.

Sophisticated may or may not have to do with "better" or works better. Thats two different topics..  I did not say it was better, I said it was more sophisticated.  Sophisticated (of a machine, system, or technique) developed to a high degree of complexity. 

As far as emissions, I dont care except  to say this.  As the rules get more strict (and it is called euro 4), they have to do something.  Look at the exhaust on the 2016 zx14. You want that?  Or, might it be nice if Suzukis new system cleans up emissions enough  where the 100lb exhaust is not necessary?









 
By the way, did you guys notice that new 2017 Suzuki sv 650 is rated at 71mpg?  Suzukis claim, but 3.8 fuel capacity and 71 mpg is not too bad for range.

I will be interested to see what Kawasaki does with the concours 14 in regards to the new MOTORCYCLE euro 4 emissions, Will it get retuned, and  a monster exhaust system or will Kawasaki do something like suzuki did with the sv?

 
BTW, I posted the question on cam timing because I think they got it backwards, either on purpose or to confuse. y'all should look up the effect of advancing the intake cam for top end by gaining overlap. by my measurements, that's how the c-14 does it. Steve
 
Steve, I wondered about that, but I remembered going to the last wsbk race we had here in Utah.  That was 2011.

You rarely get to hear this on tv, but up close you could hear the Kawasaki "missing" like crazy.  Oddly enough, the missing coincided with every slow corner.  The bike "misfired' in any track section where ultimate  horsepower was not needed. Lost of time spent riding on 2 or3 cylinders, but the sound said "not all four". Most of the videos have music dubbed over it to prevent you from hearing the sounds.  Its poor audio, but you can almost hear it here at about the :27 second mark, but oddly enough the video cuts away just then....

https://www.youtube.com/watch?v=dBpXJZce538

Back to the original article, had the author said' wsbk, Id have believed him.  I wondered if Suzuki is using this system not for the ultimate horsepower advantage, but as a way to make more manageable low -mid power?

At the same time, maybe emissions are improved by keeping valve timing closer to optimum throughout the rpm range?







 
Steve in Sunny Fla said:
BTW, I posted the question on cam timing because I think they got it backwards, either on purpose or to confuse.

Yeah, that's the second thing I saw, the first being the news about getting around the MotoGP rule. It goes against the grain and, in thinking about various timing and overlap possibilities, I'm at a loss. WAG - both cams slightly advanced for low end power, and then using this system to retard the intake to bring back some high end power? But that doesn't make sense either because it would educe the overlap.  :mad:

Roland - you totally doubted what was written in the article I linked, claimed it had to be about superbike, not MotoGP, threw out some unrelated crap about Yamaha and Suzuki using pneumatics instead of springs - which had nothing to do with the conversation - added in some nonsense about emissions which don't apply, and then shouted at us to challenge you on your misinformation all the while claiming it was the truth. So yeah, you started the crap. If you can't take it, stay out of the forum.

And I'm so glad you can read Webster's, good for you. But in mechanical engineering, many times something can be considered to be sophisticated for its lack of complexity. But since you seem to have spent a lot of money on the latest and greatest, and all the shiniest (squirrel), you have the expectation that what you have invested in must be the most sophisticated. I get it. Having bubbles burst is a bitch.
 
So I've been thinking about it, and in street automotive, or in the case of the c-14, The cam timing is short because that's where the vehicles spend most of thier time, and then the occasional foray into upper rpms gets more overlap for more peak hp. Maybe the racers are doing the exact opposite, long cams high overlap for peak HP, and then retarding the intake for less overlap at low rpm. In that case, the ordinary position of the balls would be in the out position, and they would generally be trying to migrate in.  Steve
 
I dont quite understand your anger. We could just move on and discuss this like adults.  It is an option.

I was not stating facts I knew nothing about. Like your euro 4 emissions rant. Worth noting is you have yet to respond to that, have you?

I was asking questions and wondering.  The reference to honda and yamaha made sense if you understood the topic.  The point you misssed was this:

Would suzuki spend a ton of research money on a valve system thats not as "good" as what the competition is using?  I dont think so, so what really going on? Opening valves, with cams is outdated technology in moto gp when the competition uses air.

Emissions not applying?  Thats not true.    This is from last years rule book. Maybe different for 2016

Factory Option Factory Option, with concessions  Open class
Fuel 20 liters       24 liters (22 liters)*                 24 liters

If someone came out with anything that improved fuel mileage, and let them make full power  for the entire race, it would be a big deal. This is what I meant by emissions. Reduced fuel consumption is  a big deal in moto gp.
 
Steve in Sunny Fla said:
So I've been thinking about it, and in street automotive, or in the case of the c-14, The cam timing is short because that's where the vehicles spend most of thier time, and then the occasional foray into upper rpms gets more overlap for more peak hp. Maybe the racers are doing the exact opposite, long cams high overlap for peak HP, and then retarding the intake for less overlap at low rpm. In that case, the ordinary position of the balls would be in the out position, and they would generally be trying to migrate in.  Steve

Steve, it appears the "latest and greatest" 1000cc machine is Yamahas r1. We wont talk about its gear recall, but...in local races its doing rather well and finished 1 or 2 in shootouts.

Have you seen its dyno chart?  Its here, compared with the others:

http://www.motorcycle.com/blog/wp-content/uploads/2015/07/070215-2015-Literbike-Shootout-hp-Dyno-1-547x389.jpg

With bikes reving to 14,000 rpm, I'm not sure where low to mid power really is, but at 7000 rpm, is down 20 hp as compared to the rest.  Yet its power get praised.

So, back to suzuki.  Maybe this system has nothing to do with ultimate, dyno shredding power.  Might it just be about controllable power?

You can go clear back to their 2005 gsxr 1000. With a full exhaust, an 05 gsxr 1000 has way more power than this new r1.  Everywhere on the dyno chart. The old gsxr wont rev to 14,100, but that would be its only "fault".  The euro r1 has more top end power, but as compared to the American version, its no contest.

Plus,  having cam timing more ideal for any fixed rpm will reduce emissions.  They say the exhaust on the 2012 kawasaki zx14 weighs 45lbs. It will be even heavier on the 2016.  Suzuki could never do that on a gsxr.
 
Here we go again.
That dyno chart is missing the truly important data point........... TORQUE!!!!!  This is what gets the bike moving NOT HP!  The R1 may, ( I say may because I have not seen the torque numbers, but if the power is being praised then it is a fairly safe bet it has a great torque curve to make up for the lower top end HP), have a substantially better torque curve down low and that would make it a much more fun bike to ride around town and on a tight track if you aren't wringing it out at every turn. Torque is why I love throwing the C14 around on a tight track, feeling that pull without having to rev the snot out of it is awesome!
Matt

 
Matt, Yes, I should have linked that. You would think high torque, but with regards to torque, its terrible, if high numbers is the goal.

http://www.motorcycle.com/shoot-outs/2015-six-way-superbike-track-shootout-video/attachment/070215-2015-literbike-shootout-torque-dyno-1

It feels like the chart shows.  That has to be the silliest thing said, so far, but theres a good hit  right at 7500 rpm.  Despite being a real 1000 cc machine, you'd swear "750" when it leaves a stop sign.

There has to be some other component in this we cant assign number to? And this component we cant put  a number on..Is Suzuki after THAT with their new arrangement. Based on what the tests say about this r1, this is the goal. Not huge power, everywhere.




 
Wow, well based on the dyno chart, the BMW crushes everything... at least if I had to pick a bike based on a dyno chart alone, that would be it.

the praise for the yamaha probably comes from the "feeling" of power as it gains power over 7500 rpm. This isn't that is making so much power up high, it's that it was so sorry down low, so the rush of power is more noticeable. OTOH, the BMW will just pull your arms out of the sockets everywhere all the time so there's no rush, just great linear power.

  BTW, Linear power is the only way to go, when I tune that's exactly what I'm trying to achieve. Steve
 
Steve, as you saw, the only way (on paper) it will compete and beat the bmw is to stay above 7000 rpm. You'd have to assume if the race was happening under 5000 rpm, the bmw would be long gone before the yamaha ever came on pipe.

If this is how its done, on the track, suzuki now invests a bunch of money and technology into something that improves low to mid power..that no one cares about, or uses? No way would they do that.

So, like you, I'm thinking that article was mis-interpeted, or ???

 
rcannon409 said:
Steve, I wondered about that, but I remembered going to the last wsbk race we had here in Utah.  That was 2011.

You rarely get to hear this on tv, but up close you could hear the Kawasaki "missing" like crazy.  Oddly enough, the missing coincided with every slow corner.  The bike "misfired' in any track section where ultimate  horsepower was not needed. Lost of time spent riding on 2 or3 cylinders, but the sound said "not all four".

That "missing" sound doesn't have anything to do with cam timing, and it certainly isn't an actual "miss'; it's the traction control. You only heard it on slow corners because that is when it is in effect the most.
 
Steve in Sunny Fla said:
So I've been thinking about it, and in street automotive, or in the case of the c-14, The cam timing is short because that's where the vehicles spend most of thier time, and then the occasional foray into upper rpms gets more overlap for more peak hp. Maybe the racers are doing the exact opposite, long cams high overlap for peak HP, and then retarding the intake for less overlap at low rpm. In that case, the ordinary position of the balls would be in the out position, and they would generally be trying to migrate in.  Steve

Yeah... except when you look at the design, the balls move out as rpm's rise. Think about it - how would the balls move inwards when centrifugal force was moving them outwards? Even with reversed sheaves, it wouldn't happen. That is what is so confounding about this design. I'm trying to find the US patent application for this, I've seen a couple of pages excerpted from the patent, but none that address the actual mechanism.
 
rcannon409 said:
I dont quite understand your anger. We could just move on and discuss this like adults.  It is an option.

I was not stating facts I knew nothing about. Like your euro 4 emissions rant. Worth noting is you have yet to respond to that, have you?

I was asking questions and wondering.  The reference to honda and yamaha made sense if you understood the topic.  The point you misssed was this:

Would suzuki spend a ton of research money on a valve system thats not as "good" as what the competition is using?  I dont think so, so what really going on? Opening valves, with cams is outdated technology in moto gp when the competition uses air.

Emissions not applying?  Thats not true.    This is from last years rule book. Maybe different for 2016

Factory Option Factory Option, with concessions  Open class
Fuel 20 liters       24 liters (22 liters)*                 24 liters

If someone came out with anything that improved fuel mileage, and let them make full power  for the entire race, it would be a big deal. This is what I meant by emissions. Reduced fuel consumption is  a big deal in moto gp.

And again, you totally miss the point, Roland. Just to clarify, I'm not angry, I'm frustrated. Frustrated by your clear lack of knowledge. You don't seem to understand racing vs street bikes. You don't seem to understand development for racing in MotoGP vs development for Superbike (which requires street bile homologation). You don't seem to understand the difference between how valves are opened vs how that opening is timed. And you don't seem to understand the difference between emissions and fuel consumption. All boiled down into Matt correcting you on the sound you heard from the Kawi's not "missing" because of some sort of timing built in to the ECU, but actually due to the traction control. Something that was clearly obvious in last years WSB at Laguna, especially in the infield turns. And you should have heard the enormous exhaust gas detonations when they hit the rev limiter going up the hill out of turn 5. But wait, you probably thught they weren't tuned properly.

Sigh. I'm done wallowing (southerners will get the reference). All I wanted to do was post some neat info about the newest manufacturer in MotoGP and all you wanted to do was cast stones. "Can't be true!"  Whatever.  ::)
 
You did an awesome job on euro 4, dont forget that. You learned us something there.  When I said, "You rarely get to hear this on tv, but up close you could hear the Kawasaki "missing" like crazy.  Oddly enough, the missing coincided with every slow corner. "

That was called "Tongue in cheek"    Yes, I'm well aware of traction control. Several of my bikes have it, and I've heard it.

Missing from traction control. Lets think about just that.  Its pretty much the same point as if the ecu is telling the bike, "We dont need full power in this position".  Of course its traction control, but was implemented not from cam timing, or mapping,  but from actually dropping two cylinders (I believe 2 and 3) as confirmed by Kawasaki France.  In 2011, they did not have ride by wire and this was a fast and easy way to add "traction control" without a ride by wore ecu. I'm sure you invented that, right?

You posted a poorly written article and got scared when someone wanted to talk about it. As you said, "Suzuki is a small company" they cant use moto gp technology and not use it on the street. or wouldn't..or did not have the money to...You said soemthign like that, and I agree.

But when I started thinking about how it would come to the street, you got scared and lashed out.

Sadly, you never came close to explaining, or offering a thought as to why Suzuki might want this on a  moto gp machine. From what Steve said, he thought the system was to improve low-mid power (as described)  which would be odd on a machine not especially dependent on low-mid power.

What I never understood is the venom you threw out. That made you look like an idiot.  I'd rather learn about something than attack others.



 
I dont think theres a rule issue, is there?  A heated discussion, for sure, but not much more.

I think if he and I met, there would be  a handshake more so than punches thrown.  Yes, its nice when everyone can be buddy-buddy, but I've learned a lot from threads where people did have some passion and thought involved, and I feel like this thread has that. 


 
JPavlis_CA said:
Steve in Sunny Fla said:
So I've been thinking about it, and in street automotive, or in the case of the c-14, The cam timing is short because that's where the vehicles spend most of thier time, and then the occasional foray into upper rpms gets more overlap for more peak hp. Maybe the racers are doing the exact opposite, long cams high overlap for peak HP, and then retarding the intake for less overlap at low rpm. In that case, the ordinary position of the balls would be in the out position, and they would generally be trying to migrate in.  Steve

Yeah... except when you look at the design, the balls move out as rpm's rise. Think about it - how would the balls move inwards when centrifugal force was moving them outwards? Even with reversed sheaves, it wouldn't happen. That is what is so confounding about this design. I'm trying to find the US patent application for this, I've seen a couple of pages excerpted from the patent, but none that address the actual mechanism.

  we're clearly in agreement. I expect the cam timing was selected for when the balls are out, and when they migrate inward as rpms slow, the cam retards. So it's a racing cam that gets mellowed out, not a street cam that gets pumped up. Steve
 
Steve in Sunny Fla said:
  we're clearly in agreement. I expect the cam timing was selected for when the balls are out, and when they migrate inward as rpms slow, the cam retards. So it's a racing cam that gets mellowed out, not a street cam that gets pumped up. Steve

Except... Suzuki's press release clearly states it retards the cams at. I'm having trouble thinking they lied about this, other than to confuse the other manufacturers for a bit. But then, head games are pretty common in racing.  ;D

Did you have a chance to look at the pictures included with the article on the MCN website?
http://www.motorcyclenews.com/news/2016/january/secrets-of-suzukis-vvt/
 
You know what sound cool about Suzuki's system?  It sounds like it works within a "range" vs an on/off switch.

Granted, if I mention vfr 800, its not really fair. Honda disables valves opening on that bike, but I dont think suzuki's system will do this. They say the new generation vfr is better, but I wont be finding out.

http://www.sportrider.com/sites/sportrider.com/files/styles/medium_1x_/public/import/page_element_images/146_0502_32_z%2Btorque_dyno_chart%2B.jpg?itok=R0vNUkkB

Look at what happened at @7000 rpm.  Almost instantly, the bike picked up 20 hp. It looks fun, but not really. It did not feel like a fast bike. It felt like a 300 ninja that turned into an 800 at 7k.

I remember back in the 80 and 90's. Suzuki might have been one of the smaller manufacturers, but their bikes never reflected that.  Both offroad, and onroad had some good, solid and quality machines.
 
JPavlis_CA said:
Steve in Sunny Fla said:
  we're clearly in agreement. I expect the cam timing was selected for when the balls are out, and when they migrate inward as rpms slow, the cam retards. So it's a racing cam that gets mellowed out, not a street cam that gets pumped up. Steve

Except... Suzuki's press release clearly states it retards the cams at. I'm having trouble thinking they lied about this, other than to confuse the other manufacturers for a bit. But then, head games are pretty common in racing.  ;D

Yes, I looked at the pics. And I have found that trusting printed reports is a waste of time. Heck you should have been there when Kaw was debuting the c-14 in Daytona in early 2008; A bunch of us Coggers were getting a walk around by one of the sales folks, The other guys pushed me to the front to ask Q's about the VVT... the explanation I got was that it was built with counterweights like a mechanical distributor advance or a compression release  :-[ :-[  Steve

Did you have a chance to look at the pictures included with the article on the MCN website?
http://www.motorcyclenews.com/news/2016/january/secrets-of-suzukis-vvt/
 
Steve, I dont believe anyone knows more about the c14 than you do.  If your not an expert, I dont know who is.

VVT and the c14.  Did we gain anything with their choice to use this?

I know the theory part, but if the c14 dyno chart (hp and torque) is compared to the 2008 zx14.....

If we use this chart:

http://www.motorcycle-usa.com/photogallerys/2008_zx14_busa_dyno.jpg?378220    and

http://www.motorcycle-usa.com/2008/01/article/2008-kawasaki-ninja-zx-14-comparison/

I know both bikes are restricted and your version would look much better, but stock for stock its tough to find a plus side, isn't it? Or am I not seeing it?

 
Yeah, the torque on the zx14 is a mess until 4000 rpm. I have a lot of experience on the c-10, and they did the same thing with that and the zx1000 ninja, the cams were 15* longer on the ninja, and the cams are 15* longer on the zx14, I know because I timed them.

  Now along the way "back in the day" I installed zx1000 cams into the c-10. Below 5000 rpm the stock c-10 was faster, it would pull away easily on roll ons. from 5-7k, they would tie, and from 7k up the zx cams pulled away hard.

  Moving on, I developed my own cams for the c-10. 15* shorter than stock c-10's. Everyone loves them, bike has all kinds or torque, very throttle responsive. This is how the bike "shoodaben".

  Apply that to the c-14 / zx14 comparison. the c-14 is much cleaner and stronger running down low. Shorter cam timing looking even shorter by sitting at a 122*LC intake. So yeah, I think Kaw did fine with the c-14.

  And just as a point, I think Fred Harmon knows more about the bike overall than I do. He has really racked up an amazing amount of information in the compilation of Concourier tech articles he's done. Steve
 
Any updated info on the New Suzuki?  All Ive seen, so far, is a few pics of the new gsxr.

One of the British mags said Suzuki has "30 new models that will be released during the next 18 months."
 
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