ZX-12R Build

[FastBikes4Life]

I know this is a Hayabusa sight but I'm looking for some help from anyone who's done a 12 [or knows anyone who's done a 12]. I'm in the process of building a 2000 ZX-12R into a 1393cc beast. I'm starting with a JE 1287 piston kit, having cams done by Orient Express and having a crank done by Muzzys [4.6mm stroker]. When everything is said and done I'm expecting a 210 horsepower, 1393cc motor. One concern I have is the piston/valve clearance. The last thing I need is to dump money into the motor only to have the piston and the valve come together and ruin everything. Muzzys sells case spacers that they claim will help but even they stated that I may need some material removed from the pistons. I know alot of you have built 1397 (and larger) motors. What are some other issues I should expect with this project? Thanks.

Fast

[Spaz Racing]

I have done a few. I did a head for someone in Indy and with a two mill piston kit, my ported head stock cams not even degreed in made 190-195hp on ryan schintz dyno.

[gnd111]

You can get 195rwhp with a 1287 and a ported head.  Try www.bikeland.org or even PM Entropy on here as he is a Kaw guy...

[Competition CNC]

You can get 195rwhp with a 1287 and a ported head.  Try www.bikeland.org or even PM Entropy on here as he is a Kaw guy...

Very true.
And the stroker will be even stronger, you can get into the 220hp range.
I have a 1375.

Watch for piston to head clearance.  You will need to play with the shims under the block.

[Spaz Racing]

It was on pump gas also I believe.

[Jay]

What rods are you using? If stock length you will need a spacer.




The entire kit.

http://zxzone.com/

[FastBikes4Life]

What rods are you using? If stock length you will need a spacer.




The entire kit.

http://zxzone.com/

Yes, I'm going with the stock rods. Muzzys sells spacers that help with this problem. In fact, both techs I spoke to said I would need to go with an upper and lower case spacer. I'm guessing this will keep the valves from slamming into the pistons. I'm very excited about this project because the stroker crank with the 1287 piston kit is going to make for a huge engine (something like 1393cc) with torque down low and power up top. Add to that the Orient cams and who knows what's going happen? 

Fast

[entropy]

"In fact, both techs I spoke to said I would need to go with an upper and lower case spacer..."

huh?????

stroked 12 can be a really fun machine.

Make sure yr builder knows what he is doing.

If you be double damn sure of quench height, cam CL's, PTV, piston/cylinder, rod & main clearance, it'll live a long time and toast tire after tire after tire.

are you buying the pistons/cyl as a kit?  If not, triple check clearance

[sm2w]

All you will need is one spacer plate if you are using stock rods and you should be able to get it from Muzzy and make sure that you have at least .040 piston to head clearance.

[Jay]

Here you go. Run the .100 and leave the base gasket out.

ZX12 Spacers

[FastBikes4Life]

"In fact, both techs I spoke to said I would need to go with an upper and lower case spacer..."

huh?????


That's what they said. I asked both of them. But it sounds like I may need only 1????

Here you go. Run the .100 and leave the base gasket out.

ZX12 Spacers

You guys will have to forgive my ignorance. I had a turbo thrown on a GSX-R1000 but buidling the motor seems a lot more involved and I think I'm going to learn a lot along the way.

"are you buying the pistons/cyl as a kit?  If not, triple check clearance"

I wish they were kitted. The 1287 pistons are from JE and I'm going to send the block to Millennium for boring/replating. While that's getting done the tuner can hopefully get the crank in and straighten out the issues with the tranny. I found a guy selling some Carrillo H beams for the ZX-12R. Do I need them or can the stockers handle the extra?  I'm guessing I'll see right around 200 to 210 horses. Thanks.

Fast

[entropy]

send the pistons with the block to millennium, tellum what clearance you want.
(i aim for .0020")

For a stroker, using carrillos will require clearancing the starter gear and the lower case under #4 rod. 
lotsa folks seem to do fine with stock rods.

i use carrillos, but i run very tight PTV and quench and worry about rod stretch.
do carrillos stretch less than OEM?  i dunno, the carrillos just make me feel better

[TRNorBRN6001]

Great info from all the above people. Entropy is the Man when it comes to ZX-12's. Jay is a great guy as well, he'll set you right on the spacer plate and i'd bet he could set you up with some head studs as well. Be sure to check out BikeLand as mentioned above, Dragbike and ZX-12 areas. Be sure to check out KZScotts build over there. Once you have it built, be sure to come down to the Texas Mile to break it in. If you are going to be running mainly on the street and live in the South, watch out for traffic, cause it'll want to over heat. Manual fan switch or lower fan temp switch will help a little bit in the begining. Maybe add a couple extra piston oil squirters as well.

[FastBikes4Life]

Great info from all the above people. Entropy is the Man when it comes to ZX-12's. Jay is a great guy as well, he'll set you right on the spacer plate and i'd bet he could set you up with some head studs as well. Be sure to check out BikeLand as mentioned above, Dragbike and ZX-12 areas. Be sure to check out KZScotts build over there. Once you have it built, be sure to come down to the Texas Mile to break it in. If you are going to be running mainly on the street and live in the South, watch out for traffic, cause it'll want to over heat. Manual fan switch or lower fan temp switch will help a little bit in the begining. Maybe add a couple extra piston oil squirters as well.

send the pistons with the block to millennium, tellum what clearance you want.
(i aim for .0020")

For a stroker, using carrillos will require clearancing the starter gear and the lower case under #4 rod. 
lotsa folks seem to do fine with stock rods.

i use carrillos, but i run very tight PTV and quench and worry about rod stretch.
do carrillos stretch less than OEM?  i dunno, the carrillos just make me feel better

I can't tell you how much I appreciate all of this. So Millennium will take some material off the top of the pistons for me? That's pretty cool. That won't be overkill with the spacer will it? It also sounds like the stock rods should be able to handle the power.

Mainly this bike will see around-town and highway riding. I really wanted to put together a fast bike that had some nostalgia to it. Since 2006 (when Kawi stopped building the 12) I always felt like it was the forgotten warrior. It lived its entire existence in the Busa's shadow and now that the ZX-14 is out there NO ONE talks about ZX-12Rs anymore. You could probably get more discussion out of folks about the ZX-11 than the ZX-12R so I wanted to build one that would do all ZX-12Rs proud. Sounds stupid, I know but it's what I want to do.

Fast

[gnd111]

So Millennium will take some material off the top of the pistons for me? That's pretty cool. That won't be overkill with the spacer will it?

Clearancing the pistons won;t affect anything more than PTV - not CR...

[Mospeada]

Mainly this bike will see around-town and highway riding. I really wanted to put together a fast bike that had some nostalgia to it. Since 2006 (when Kawi stopped building the 12) I always felt like it was the forgotten warrior. It lived its entire existence in the Busa's shadow and now that the ZX-14 is out there NO ONE talks about ZX-12Rs anymore. You could probably get more discussion out of folks about the ZX-11 than the ZX-12R so I wanted to build one that would do all ZX-12Rs proud. Sounds stupid, I know but it's what I want to do.

What's a ZX-12R?





























Sorry, couldn't help myself.

[entropy]

I sure was not clear in my notes above, maybe this will help.

3 issues with "piston clearance"
(I hope the experts will forgive/correct my explanation)

1) piston to bore clearance: .0020-.0030". 
I like tight, but be careful and warm it up before stressing it
Millennium will plate the cylinder bores, then hone them down to a size which gives the correct Piston-to-cylinder clearance.
When you buy a kit (block+pistons) that clearance has already been accomplished but always good to check.

2) piston to head clearance as it goes thru TDC = quench/squish height
 a safe quench = .040",
lotsa folks go tighter, but gotta be careful.
Quench is impacted by cy block height, rod length, base spacer, base gasket, head gasket, piston design.

3) Piston To Valve clearance:  as the exh valve closes and intake opens during overlap and piston goes thru TDC, piston gets closest to valves.
axial: Exh PTV =.080", int PTV = .060" is safe;
 lotsa folks go tighter, but be careful
PTV is impacted by piston valve pocket depth, quench, how much the head is skimmed, how deep the valve seats are sunk, how "big" yr cams are, what CL's you have the cams set at, even lash setting.

I hope this doesn't muddy things...

Great info from all the above people. Entropy is the Man when it comes to ZX-12's. Jay is a great guy as well, he'll set you right on the spacer plate and i'd bet he could set you up with some head studs as well. Be sure to check out BikeLand as mentioned above, Dragbike and ZX-12 areas. Be sure to check out KZScotts build over there. Once you have it built, be sure to come down to the Texas Mile to break it in. If you are going to be running mainly on the street and live in the South, watch out for traffic, cause it'll want to over heat. Manual fan switch or lower fan temp switch will help a little bit in the begining. Maybe add a couple extra piston oil squirters as well.

send the pistons with the block to millennium, tellum what clearance you want.
(i aim for .0020")

For a stroker, using carrillos will require clearancing the starter gear and the lower case under #4 rod. 
lotsa folks seem to do fine with stock rods.

i use carrillos, but i run very tight PTV and quench and worry about rod stretch.
do carrillos stretch less than OEM?  i dunno, the carrillos just make me feel better

I can't tell you how much I appreciate all of this. So Millennium will take some material off the top of the pistons for me? That's pretty cool. That won't be overkill with the spacer will it? It also sounds like the stock rods should be able to handle the power.

Mainly this bike will see around-town and highway riding. I really wanted to put together a fast bike that had some nostalgia to it. Since 2006 (when Kawi stopped building the 12) I always felt like it was the forgotten warrior. It lived its entire existence in the Busa's shadow and now that the ZX-14 is out there NO ONE talks about ZX-12Rs anymore. You could probably get more discussion out of folks about the ZX-11 than the ZX-12R so I wanted to build one that would do all ZX-12Rs proud. Sounds stupid, I know but it's what I want to do.

Fast

[FastBikes4Life]

"I sure was not clear in my notes above, maybe this will help.

3 issues with "piston clearance"
(I hope the experts will forgive/correct my explanation)

1) piston to bore clearance: .0020-.0030". 
I like tight, but be careful and warm it up before stressing it
Millennium will plate the cylinder bores, then hone them down to a size which gives the correct Piston-to-cylinder clearance.
When you buy a kit (block+pistons) that clearance has already been accomplished but always good to check.

2) piston to head clearance as it goes thru TDC = quench/squish height
 a safe quench = .040",
lotsa folks go tighter, but gotta be careful.
Quench is impacted by cy block height, rod length, base spacer, base gasket, head gasket, piston design.

3) Piston To Valve clearance:  as the exh valve closes and intake opens during overlap and piston goes thru TDC, piston gets closest to valves.
axial: Exh PTV =.080", int PTV = .060" is safe;
 lotsa folks go tighter, but be careful
PTV is impacted by piston valve pocket depth, quench, how much the head is skimmed, how deep the valve seats are sunk, how "big" yr cams are, what CL's you have the cams set at, even lash setting.

I hope this doesn't muddy things..."


What's that smell? Now I feel something sliding down the back of my throat. Oh, that's just my brain melting and oozing out of my skull. Just kidding - that all sounds very technical but what I will probably do is have my tuner send the pistons with the head and explain to Millennium what I'm trying to achieve. I'm pretty sure Millennium will know what to do and I have a lot of confidence in the tuner I'm using for this project. For anyone in Chicago his name is Bill Pehanich (Billy P.) and he runs BPR) Racing in Crestwood, IL. I used Elton Fish of EFR Racing for my turbo (another great, great tuner) but the drive out to his place from mine was a bit much.

What is quench/squish? Thanks.

Fast

[entropy]

if you have a "builder" rather than a "bolt stuff together-er" he'll know all that stuff & more.

You gotta be REAL careful when you buy separate aftermarket parts to build a perf motor.  Gotta measure EVERYTHING, or risk a case of the Big Bang.
Aftermarket kits are much easier, but even with them it is wise to measure.

Quench/squish is the distance from the flat area around the outside of the top of the piston and the head when the piston is at TDC

[Jay]

if you have a "builder" rather than a "bolt stuff together-er" he'll know all that stuff & more.

Boy, that is the key right there!!!!

[FastBikes4Life]

if you have a "builder" rather than a "bolt stuff together-er" he'll know all that stuff & more.

You gotta be REAL careful when you buy separate aftermarket parts to build a perf motor.  Gotta measure EVERYTHING, or risk a case of the Big Bang.
Aftermarket kits are much easier, but even with them it is wise to measure.

Quench/squish is the distance from the flat area around the outside of the top of the piston and the head when the piston is at TDC

Billy really knows motors. I have a lot of confidence in his abilities. His main challenge is equipment. If he could do all the work himself I'm pretty sure he would. He's a skeptic when it comes to other people's work and only trusts a few people to handle his clients' stuff. And thanks for the explanation of quench/squish. I had no idea.

Fast

[Jay]

Looking for a good set of clean ZX12 cases for a customer. Let me know what you have  jay@aperaceparts.com

[TRNorBRN6001]

Maybe give Bikeland.org a try.

[jarim]

Few weeks ago I ran 1430cc ZX-12R having ~230hp in a top speed test day. 322km/h. And I have ran 325km/h with my 1397cc Hayabusa having ~200hp for same distance. So why bother with Kawasaki? 

[FastBikes4Life]

Few weeks ago I ran 1430cc ZX-12R having ~230hp in a top speed test day. 322km/h. And I have ran 325km/h with my 1397cc Hayabusa having ~200hp for same distance. So why bother with Kawasaki? 

I found the bike for dirt cheap with very little wrong with it and I feel the ZX-12R has always been overlooked. There are some very fast 12s out there and I want to build one here in Chicago. Most of the ZX-12Rs in Chicago see a Muzzy pipe, a PC, some filters and that's it. I want more, much more outta' this ZX-12R.

Something else I really like about the ZX-12R is it's only 1 inch longer than a GSX-R1000. When running with my friends through some twisties they cannot put a significant gap between us no matter how hard they try. The 12 likes twists and in the higher RPMs it's a real muther-fugger trying to outrun. I really like the bike and I'm trying to improve on what I think is a decent platform.

And don't forget, the Hayabusa's aerodynamics are much better than the ZX-12R's. It takes boatloads more horsepower to push the ZX-12R through air at those speeds than the Hayabusa. Once over 200 mph it's a wrap. The Hayabusa slices the wind while the 12 just sorta' pushes it out of the way. Big difference when you're going for top speeds.

Now check this out - someone here wrote that they were running a 1375. Any problems with the motor? I ask because the other day I told my tuner what I was planning and he told me that a stroker crank simply places too much stress on the bearings for street riding. He said strokers are for racing ONLY!!  Now, most of his experience is with Busas but I trust this guy. Has anyone faced breakdown or other issues running the strokers as daily riders? Thanks.

Fast