Cylinder head size

Moderator: Moderators

Post Reply
neston
Posts: 15
Joined: Mon Nov 17, 2014 10:11 am
My Bike: Kawasaki ZXR400 racer

Cylinder head size

Post by neston » Sun May 05, 2019 5:05 pm

Hello,
I'm having trouble finding out the standard size of a ZXR400 cylinder head , I need to know the height of the head in order to find out if a head has been skimmed and by how much ?
I searched all the manuals and no luck at the moment.
All the best from Neale.
Thanks in advance.

User avatar
banner001
Track day God
Track day God
Posts: 2370
Joined: Sat Sep 24, 2011 3:27 pm
My Bike: ZXR400 L4
Location: Nuneaton

Re: Cylinder head size

Post by banner001 » Sun May 05, 2019 7:50 pm

I've got an L4 head In the garage, to my knowledge it has never been skimmed, I'll go and grab the size in a sec...
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

User avatar
Miles
zxr400 oc member
zxr400 oc member
Posts: 461
Joined: Wed Apr 30, 2008 11:00 pm
My Bike: ZXR 400 L3
Location: Bangor, Northern Ireland

Re: Cylinder head size

Post by Miles » Mon May 06, 2019 2:39 pm

Sometimes, as far as I’m aware, when the zxr 400 L heads are skimmed, the machine can ‘nick’ part of the thermostat surround.

Could be a a quick way,but not definite, to tell if a head had been skimmed before.


On a tangent, I have had to have my head skimmed twice (just the bare minimum to bring it level) I also had the barrels skimmed as they had warped as well.

This has created no issues with squish or valve/piston clearnece. In fact I had to argue with the tuner who did my head to not take off anymore. “We’re not even into the power yet” was his answer. So he reckoned there’s loads of give onthese heads. He built engines for relentless Suzuki so I’m inclined to believe him.

neston
Posts: 15
Joined: Mon Nov 17, 2014 10:11 am
My Bike: Kawasaki ZXR400 racer

Re: Cylinder head size

Post by neston » Mon May 06, 2019 5:26 pm

banner001 wrote:
Sun May 05, 2019 7:50 pm
I've got an L4 head In the garage, to my knowledge it has never been skimmed, I'll go and grab the size in a sec...

Yes, that would be very helpful, many thanks in advance from Neale.

neston
Posts: 15
Joined: Mon Nov 17, 2014 10:11 am
My Bike: Kawasaki ZXR400 racer

Re: Cylinder head size

Post by neston » Mon May 06, 2019 5:29 pm

Miles wrote:
Mon May 06, 2019 2:39 pm
Sometimes, as far as I’m aware, when the zxr 400 L heads are skimmed, the machine can ‘nick’ part of the thermostat surround.

Could be a a quick way,but not definite, to tell if a head had been skimmed before.


On a tangent, I have had to have my head skimmed twice (just the bare minimum to bring it level) I also had the barrels skimmed as they had warped as well.

This has created no issues with squish or valve/piston clearnece. In fact I had to argue with the tuner who did my head to not take off anymore. “We’re not even into the power yet” was his answer. So he reckoned there’s loads of give onthese heads. He built engines for relentless Suzuki so I’m inclined to believe him.
Thanks for your reply, I have just checked mine and the thermostat threaded boss part has been nicked ,by the skimming cutter ,maybe ?
Many thanks from Neale.

neston
Posts: 15
Joined: Mon Nov 17, 2014 10:11 am
My Bike: Kawasaki ZXR400 racer

Re: Cylinder head size

Post by neston » Tue May 07, 2019 5:29 pm

Hello,
I forgot to mention that the cylinder head I have measures 109.15 mm at the cam chain side ( No.4) and 109.25 mm at the other side ,(No.1) , both measured from the top of the head to the base of the head.
Regards from Neale.

Post Reply