In RoadRacing world..ZX-14 specs...

[mike46]

Basically, 33.4 intakes, 28.3 exhaust,  In. 9mm lift, open 41, close71 duration 292.  Ex. 8.5mm lift, open64, close34 duration 278... C/R advertised 12:1. Chamber 36cc...Bore/stroke 84 X61mm. Hmmm...the ubiquitous Yosh 105, 105 LC's.  Cam #'s checked @ 1mm.  That's a good size intake but nothing crazy. Exhaust isn't to bad IMO with the valve size.

[SLOWBUSA]

Would a Busa benefit from the oversize exhaust valves? 28.5mm Looks like going to a +2 or 3mm piston kit might need the extra flow. Maybe some 33.5mm intake valves need to be produced as most of what I have read states the 34mm is too big.

[DarkFalcon]

Interesting. Compared to the Busa, the valves are slightly larger and the intake cam is a bit more aggressive and the exhaust considerably more so. I would say the exhaust is the biggest point of departure and maybe they made a conscious decision to give up a little grunt and pick-up some mid and high-end power with a larger exhaust cam. But without head flow data and access to the high-end software like GT Power and WAVE, it's hard to put everything into perspective and understand why decisions have been made as they have. 

[mountainmotor]

Time will tell but i think we'll find later that the ZX14 use's a steeper valve angle of something like - 12 degree's Intake valve angle - 13 degree's Ex . for 25 degree's of included angle . Guessing they were aiming for high port velocity and better atomization by going with the smaller throttle body and the multi hole injector vs the 12R .

Is the ZX14 using the Tumble Effect combustion chamber design ?

[DarkFalcon]

I believe those are the same size valves as used on the ZX12 and the ZX12 has an included valve angle of 25 degrees. Now I am beginning to think the head changed very little other than what has been discussed. Weird.

other machine in its category. * Engine is approximately 12 kg lighter than the ZX1100D engine. * Bore/stroke ratio of 0.67 the same as the ZX-9R: 83 x 55.4 mm; only 3 mm longer than the ZX-9R between crankshaft and driveshaft, with overall engine length only 8 mm longer than the ZX-9R. * Direct valve actuation with crowned lifters to equalize pressure across the cam lobes and reduce wear. * Valve sizes 33.4 mm intake/28.3 mm exhaust. * Narrow valve angles (12° intake/13° ex.) are the same as those on the ZX6

[mountainmotor]

* Narrow valve angles (12° intake/13° ex.) are the same as those on the ZX6[/b]

Which is the same as the 2004 - 2005 ZX10 , just as a FWIW .

It seems Kawasaki is happy with those design parameters and their combustion chamber .

[mike46]

* Narrow valve angles (12° intake/13° ex.) are the same as those on the ZX6[/b]

Which is the same as the 2004 - 2005 ZX10 , just as a FWIW .

It seems Kawasaki is happy with those design parameters and their combustion chamber .

It appears to work.

[gazza414]

Have folks noticed what Suzuki has done to their 2006 model 600 / 750 motors as a comparision?

you might be surprised?

[DarkFalcon]

Good point...................the 2005 GSXR1000 has a 25 degree included valve angle.

[gazza414]

The 750 has gone smaller in bore and a longer stroke compared to 2005, rev limit has been upped 600rpm to now 15000rpm.
Now the point in question.... Inlet is now 10.5' ( 12' K5 ) and Exhaust 12' (13 ' K5) and they have reduced the exhaust valve dia by 1mm to 23mm.

times are changing

[DarkFalcon]

I wondering if we are witnessing an evolutionary inflection towards higher torque and higher revving engines.........now possible with new designs and materials. The narrower included valve angle would facilitate a smaller combustion chamber which is generally good but particularly so with a smaller bore. The exhaust valve got smaller because they needed space or because it is tied into a broader trend of reducing measured E/I flow ratios as a result of a better understanding of relative intake and exhaust velocities which, along with a number of other flow parameters, guide head design as much or more as bulk flow aka CFM

[mountainmotor]

Just some deduction,  be it the logical type or not    if Kawasaki has stayed with the same basic cam lobe intensities they've been using those cams are going to come in at very near  243 I - 240 E duration @ .050 lift . and I kinda doubt production units LCA's will come in at 105/105  .

Since apparently a compact engine was a design factor , the bore spacing might just allow only a 2mm overbore if that and in this thread of speculation there is one thing for certain ,

It's doubtfull Cometic will be making any block spacers for that engine 

[DarkFalcon]

Just some deduction,  be it the logical type or not    if Kawasaki has stayed with the same basic cam lobe intensities they've been using those cams are going to come in at very near  243 I - 240 E duration @ .050 lift . and I kinda doubt production units LCA's will come in at 105/105  .

I have been noodling around on a thermodynamics problem today and guessing camshaft durations all of a sudden started looking welcoming. With my own highly proprietary duration guessing algorithm the durations are.........drumroll............@ .05 .......250I and 233E. Do not attach any particular significance to this as I have not been spectacularly sucessful in anticipating either valve sizes or camshaft lifts. Below is what I predicted months back for the ZX-14:

After going back and looking at the ZX10 and the ZX12, I could see them specing out a .380 lift intake cam for 33mm valves or a .370 lift cam for 34mm valves. I think they will favor the bigger valves and the lower lift.

I had no idea that they would copy the Busa as closely as they did.

[ZEUS]

Just some deduction,  be it the logical type or not    if Kawasaki has stayed with the same basic cam lobe intensities they've been using those cams are going to come in at very near  243 I - 240 E duration @ .050 lift . and I kinda doubt production units LCA's will come in at 105/105  .

I have been noodling around on a thermodynamics problem today and guessing camshaft durations all of a sudden started looking welcoming. With my own highly proprietary duration guessing algorithm the durations are.........drumroll............@ .05 .......250I and 233E. Do not attach any particular significance to this as I have not been spectacularly sucessful in anticipating either valve sizes or camshaft lifts. Below is what I predicted months back for the ZX-14:

After going back and looking at the ZX10 and the ZX12, I could see them specing out a .380 lift intake cam for 33mm valves or a .370 lift cam for 34mm valves. I think they will favor the bigger valves and the lower lift.

I had no idea that they would copy the Busa as closely as they did.

No aint that something