Variable Valve Timing

[Tached1300]

Anyone here ridden a GSXR1000 with variable timing? Perhaps a Gen 3 Busa will have it?

I’m personally not a fan of VVT just one more thing to go wrong or to have to tune out and eliminate which is why I love the Gen 2 fairly simple and straightforward.

At least with bikes there’s no pushrods or lifters to fail...

 

[fallenarch]

Anyone here ridden a GSXR1000 with variable timing? Perhaps a Gen 3 Busa will have it?

I’m personally not a fan of VVT just one more thing to go wrong or to have to tune out and eliminate which is why I love the Gen 2 fairly simple and straightforward.

At least with bikes there’s no pushrods or lifters to fail...

I think with the Hayabusa the extra 340 cc is the VVT. The Busa motor has a natural smooth wide torque spread. Race replicas need to excel in a very narrow area at the top of the rpm range to be great racers. That makes it difficult to get the max out of them especially on the street. VVT makes the bike easier to ride. And of course you already know all that.

Suzuki has always made a big effort to make engines rideable. I remember in the 70's when the Honda Elsinores had explosive super power the Suzuki RM bikes were torquey and rideable winners. I think it is the Hayabusa's power spread that is the true secret to its longevity. This engine is amazingly easy to ride.

I'm not sure if it's possible, but I can see VVT used to help a big displacement motor meet tighter emission regs and still be able to growl. That might be interesting if it is even worth the trouble. The regulators are generally not to fond of variable polluters. The Suzuki VVT is also pretty simple. It has ball bearings and uses centripetal force to move the cams. Looks to be pretty bullet proof. Others use solinoids and motors to position the cam shafts, more complex more trouble maybe. Another thing people don't get is Suzuki is committed to getting it mechanically right. I think this is why so many Suzuki models have such staying power.

 

[Tached1300]

I think with the Hayabusa the extra 340 cc is the VVT. The Busa motor has a natural smooth wide torque spread. Race replicas need to excel in a very narrow area at the top of the rpm range to be great racers. That makes it difficult to get the max out of them especially on the street. VVT makes the bike easier to ride. And of course you already know all that.

Suzuki has always made a big effort to make engines rideable. I remember in the 70's when the Honda Elsinores had explosive super power the Suzuki RM bikes were torquey and rideable winners. I think it is the Hayabusa's power spread that is the true secret to its longevity. This engine is amazingly easy to ride.

I'm not sure if it's possible, but I can see VVT used to help a big displacement motor meet tighter emission regs and still be able to growl. That might be interesting if it is even worth the trouble. The regulators are generally not to fond of variable polluters. The Suzuki VVT is also pretty simple. It has ball bearings and uses centripetal force to move the cams. Looks to be pretty bullet proof. Others use solinoids and motors to position the cam shafts, more complex more trouble maybe. Another thing people don't get is Suzuki is committed to getting it mechanically right. I think this is why so many Suzuki models have such staying power.

I agree with you in that the 1340cc is our vvt, when Suzuki increased the stroke, displacement and compression it accomplished that goal of a nice linear power band and delivery where you aren’t lacking anywhere and it’s stealthy until you decide to release the hounds!

I was thinking that with the tighter emission regs perhaps Suzuki and others may look to employ VVT on more of their models as a means to squeak by those requirements on future models on the ragged edge

For a naturally aspirated engine there’s No replacement for displacement, added rpm can be an equalizer In race applications but you lose the broad power band desired for a street application.

 

[mjl3truck]

If you look at the variable valve timing on the GSXR1000 it is actually pretty simple.

 

[Tached1300]

If you look at the variable valve timing on the GSXR1000 it is actually pretty simple.

Thanks for posting that

 

[Boosted Cycle Perf]

I love how stupid simple that is. I wouldn’t exactly call that variable cam timing, more like progressive cam timing as its rpm based essentially.

I’m wondering when/if we will ever see direct injection on motorcycles. That would be huge. However that would turn the tuning aftermarket on its head. That would put an end to power commanders as you don’t tune DI engines with injector pulse width. You tune on something called torque request/management.

 

[fallenarch]

I love how stupid simple that is. I wouldn’t exactly call that variable cam timing, more like progressive cam timing as its rpm based essentially.

I’m wondering when/if we will ever see direct injection on motorcycles. That would be huge. However that would turn the tuning aftermarket on its head. That would put an end to power commanders as you don’t tune DI engines with injector pulse width. You tune on something called torque request/management.

DI will make bikes more efficient but will it open new performance doors?

 

[Boosted Cycle Perf]

DI will make bikes more efficient but will it open new performance doors?

Emissions aside, there’s no reason why HP wouldn’t jump considerably too. Look at the gen 4 vs. gen 5 GM V8 engines.

That’s a huge investment in R@D as the success of a DI engine largely lies on piston, and combustion chamber design. And being were just now starting to see variable cam timing on motorcycle engines, I’m sure we’re at least 8-10 years away from seeing DI on mass production motorcycles.

 

[bigoltool]

Piaggio looks to be piggybacking off of the Suzuki Mechanical VVT tech. Still scratching my head why Suzuki didn't add this (among other things) to the Gen 3 Hayabusa?

Piaggio's variable valve timing system could be used in the RSV4

Piaggio has patented a new mechanical variable valve timing system, which might see use in Aprilia's superbike efforts.

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