Camshaft Advice - Street KZ900

What about 1981 GPZ1100 cams? Are they the same profile as the 83-84?

EDIT: Nope, as far as part numbers they are different according to Kawasaki.com

Cory

You are correct...the early cams are different. The 83-84 GPZ cams have .385 lift...or there abouts. According to experts on this site, a stock 1000 head will flow enough to support up to about .360 lift. APE reported on KZRIDER a while back that they have adjustable cam sprockets to use GPZ cams with 15T center cranks.

Do you know what the lift on the earlier GPZ cams are?

Cory

We have them in both 30 and 32T

For my latest project on the KZ900, I just recently measured my new to me GPZ cams @ .373" so including caliper tolerance, .375" lift is what they are.... Got the 30 tooth 2 bolt sprockets from Jay....

As Larry knows, I prefer low to mid range torque (acceleration/pull) in my builds & as always, following Larry's guidance for my desires, 108 exhaust & 106 intake on the cam degreeing.
1075cc displacement on it's way back from Joe Hooper....

Should wake the old girl up nicely!

Bring it on Harley BIATCH's... :laugh:

OMR,

Are those specs from the 83-84 GPZ or the 81-82 GPZ?

Cory

NakedFun wrote: Do you know what the lift on the earlier GPZ cams are?

Cory

Here you go, courtesy of MFolks:



1981 KZ1100 B1 Gpz:

Intake:

Duration: 280 - Lift: 8,4 mm (.330") - Open: 35 BTDC - Close: 65 ABDC

Exhaust:

Duration: 280 - Lift 8,8 mm (.346") - Open: 68 BBDC - Close: 32 ATDC




1982 KZ1100 B2 GPz:

Intake:

Duration: 288 - Lift: 8,8 mm (.346") - Open: 34 BTDC - Close 74 ABDC

Exhaust:

Duration: 288 - Lift: 8,8 mm (.346") - Open 72 BBDC - Close 36 ATDC



Btw, the 81/82 GPz's run shim over bucket, the 83/84 models run shim under - can't say if shim under is needed for using the 83/84 cams in the 900, but I thought I'd mention it..

you don't need to go shim under until about .418" lift

Well I may just go ahead and pick up the '82 GPZ cams I found as they are relatively inexpensive. I do have time to wait a bit anyway so I can keep an eye out for the later 83-84 cams...

Cory

I don't have the actual spec sheets on them but as far as I know, 83/84 GPZ cams .375 lift 258 duration @ .050. Pretty much what I measured.

And No, I've never measured the 1981/82 cams so going w/Mfolks info is good enough for me.

Well I got a set of '81 GPZ cams for $50 bucks so even though they are not the coveted 83-84 profile, still more lift and duration than my stockers...

Cory

My cams showed up and they do not have tach drive gear on the exhaust cam? Is this normal? Any thoughts to how you setup a tach now? What ave you guys done?

Cory