Making a Kawasaki Z1 race ready. Again

dbsuperbiker wrote:

mark1122 wrote:

turboguzzi wrote: hi arthur

never worked on a 1000 so had no idea about this mod

do you know if the smaller 650-750 block should be similary protected to avoid trouble?

they might be more safe as the plain bering crank has dowels in all the cases bearing housing holes

had on my 750/810 just 4 races this season, so far so good, but would be interested to know if you ever saw similar trouble with 650-750's

tnxs

u may want to run that question by our member, Injected. he dragraces a high compresion, alcohol kz650.

He may know, I have ridden the KZ650s, but never hot-rodded them.

I don't use any case bracing at all on the 650 motor... my tire is 5.5" wide, so I don't have to use an offset on the sprocket, so there is no outboard bearing support required. With most 650/750 NA gas motors putting out around 80-95 HP I don't believe the case bracing would be required, but Drag racing and road racing do put different stresses on the motor and frames, bearing this in mind I don't think I can comment on stock 650 case fractures in road racing - I have yet to see an issues as far as drag racing goes even above 110 HP. I believe there would be greater stresses involved in road racing due to acceleration/deceleration G forces being transmitted from the chassis to the frame cases especially when solidly mounted.
Locran might want to chime in as his turbo 750 motor puts out over 200 HP...

hei injected,

nice of you chimming in

how are you these days?

not exactly worried about the cases, was just wondering if this was common practice in 650/750 too.

with the kind of power arthur is getting, internal bracing might be more critical in his 120 hp liter mill rather than my 95 hp 810cc motor.

TG

dbsuperbiker wrote: yes, seems it was about 6Hp diff....very measurable, but not earth-shaking. this engine was built to work with the smaller intake.

What make was the dyno & where was the output measured?

Nice bike you've buit BTW

LarryC wrote:

dbsuperbiker wrote: yes, seems it was about 6Hp diff....very measurable, but not earth-shaking. this engine was built to work with the smaller intake.

What make was the dyno & where was the output measured?

Nice bike you've buit BTW

check out the shape of the powerband on the screen!

Dyno Jet.... I thought so

Take a bike from a DJ straight to a SuperFlo and you'll see the numbers decline significantly. Doesn't mean the motor is any less powerful. Just means the two machines produce different results.

You certainly have large enough intake valves and enough compression to make it pull like a Mack Truck. It's got to have a big Fun Factor when it's up aroud 7000 in 3rd gear

How come you're not running CRS33 Keihins or RS34 Mikuni's on it?

I can't really see the graph in the pic very well....got a clear shot or the print out scanned?

Larry C

A 1015 KZ motor w/ 40-32 / Cam Motion Z7 Grind / 14:1 Compression 82CFM@10" Head

Crank Shaft Power

61.994 Cubic Inches @ 9000 RPM with 122.0 % Volumetric Efficiency PerCent

Required Intake Flow between 131.6 CFM and 138.2 CFM at 28 Inches
Required Exhaust Flow between 94.7 CFM and 105.3 CFM at 28 Inches

600 RPM/Sec Dyno Test Lowest Low Average Best
Peak HorsePower 148.8 154.9 158.0 161.0
Peak Torque Lbs-Ft 92.8 96.6 98.5 100.4

HorsePower per CID 2.400 2.499 2.548 2.598
Torque per Cubic Inch 1.497 1.558 1.589 1.620

BMEP in psi 225.7 235.0 239.6 244.2
Carb CFM at 1.5 in Hg. 197 219 230 241

Target EGT= 1131 degrees F at end of 4 second 600 RPM/Sec Dyno accel. test
Octane (R+M)/2 Method = 113.6 to 112.8 Octane required range
Air Standard Efficiency = 65.74910 % for 14.000:1 Compression Ratio

Peak HorsePower calculated from Cylinder Head Flow CFM only
600 RPM/Sec Dyno Test Lowest Average Best Potential
Head Flow Peak HP = 150.1 159.3 168.4

---

Piston Motion Data

---

Average Piston Speed (FPM)= 3897.00 in Feet Per Minute
Maximum Piston Speed (FPM)= 6357.32 occurs at 75.400 Degrees ATDC
Piston Depth at 75.400 degree ATDC= 1.1449 inches Cylinder Volume= 111.9 CC
Maximum TDC Rod Tension GForce= 3824.13 G's
Maximum BDC Rod Compression GForce= 2152.96 G's

---

Current Camshaft Specs @ .050

---

IntOpen= 23.00 IntClose= 63.00 ExhOpen= 63.00 ExhClose= 23.00
Intake Duration @ .050 = 266.00 Exhaust Duration @ .050 = 266.00
Intake CenterLine = 110.00 Exhaust CenterLine = 110.00
Compression Duration= 117.00 Power Duration = 117.00
OverLap Duration = 46.00 Lobe Center Angle (LCA)= 110.00
Camshaft installed Straight Up = 0.00 degrees

-Recommended Camshaft Valve Lift-
Minimum Normal Maximum
Intake = 0.355 0.382 0.421
Exhaust = 0.338 0.364 0.400
Max-effort Intake Lift = 0.441
Max-effort Exhaust Lift = 0.419
Minimum Intake Valve Lift to prevent Choke = .382 Lift @ 9000 RPM
Minimum Exhaust Valve Lift to prevent Choke = .364 Lift @ 9000 RPM

very nice!....by juggling lobe centers, ign timing, compression, intake length, and jetting some of the numbers vary a bit from your calculations. this tweaking netted me about 5 HP.
compr ended up .5 higher, ign retarded 1 1/2degrees avg, jetting fatter and lobe centers nearer to 106 and 108

Larry, AHRMA limits the 1L bikes in Superbike Heavyweight to 29mm carbs or a 29mm restrictor.

DoubleDub wrote: Larry, AHRMA limits the 1L bikes in Superbike Heavyweight to 29mm carbs or a 29mm restrictor.

Thank You

dbsuperbiker wrote: very nice!....by juggling lobe centers, ign timing, compression, intake length, and jetting some of the numbers vary a bit from your calculations. this tweaking netted me about 5 HP.
compr ended up .5 higher, ign retarded 1 1/2degrees avg, jetting fatter and lobe centers nearer to 106 and 108

Very good work on your part. I sincerely mean that too

How much cam are you running in it?

Ever tried a rack of CRS31 Keihins on it with the sort stacks?

Here's a customer's sheet from some DJ Dyno in California a couple of years back. 1075 street motor with 10.25:1 Wisecos, 29 Mics, 83 CFM steet head with 36/30, Web 110s


Here' part of the notes I got with the dyno sheet scan

Last year before the rebuild 74HP at 8250, 55ft lbs at 7300

On the first pull Dusty whacked the throttle (he drag races) around
3500 and it stumbled and fell on its face. Still wound it out to 7900K
(where dyno stopped recording) where it looks like power curve started
flattening out, at 104HP, torque max 75ft lbs at 6500.

Second pull he rolled it open quickly instead of whacking it down low
and it pulled clean but recording stopped at 7300. 103 HP at 7300 and
77ft lbs at 6250.

Air/fuel with standard jets #25 pilots 14.6 at idle.
Second pull had sniffer running 2900-7300 rpm 14.7 at 2900 14.4 at 4K
going up to 14.6 the rest of the ride at WOT.

.420 cams
the carbs I use are not optimum, but were best ones avail to me and legal for AHRMA several years ago.
If I was seriously trying to take advantage of todays rules and once again compete for a championship, I would change carbs and exhaust system.
As it is, still legal, runs pretty good and authentic.
BTW, yes it is a big handful at 7000 in 3rd gear, especially when geared for a shorter road course :woohoo:

Every time I check back on this thread, I'm amazed! Art, any chance of posting a video of your next dyno run? That'd cause many sleepless nights for most of us. :laugh:

Do you have several transmissions, all with different gear ratios, custom suited for various courses?