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Discussion Starter · #1 ·
My ZR7 has received one more modification from its new owner!

With minor modifications, the camshafts were installed successfully.
The mechanic explained to me what he did, and it's quite easy to do.
The head is different and so far we thought that it was impossible to install GPZ cams, but it is possible.
The gains are not known yet, as he couldn't ride the bike hard before and after, so I have to ride the bike and judge the difference.
Of course the dyno will also tell us how it went, the 'before' dyno reading is 69,7 HP at 9000 with a nice curve.
I expect the power now to be around 73-75 at sligthly higher rpm.
One side effect is that the exhaust is making really loud bangs now when you chop the throttle.
It was backfiring before but now it's 2 times more!

I will keep you updated!
 

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I have 5 sets of GPZ cams. Please explain the installation procedure.
 

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Discussion Starter · #3 ·
Basically, the ZR7 head has slots at the left side, in which the camshaft ends sit firmly so that it can't moce left to right.
What he did, in order to install the cams in the ZR7 head, was to insert custom made spacers in the head slots, and also 2 axle clips (i'm not sure how they are called in english, but I mean the circular clips we use to secure an axle), one in the grooves between the 2nd and 3rd lobe and another between the 3rd and 4th.

I didn't see the actual installation, but he explained to me what he did and he showed me the positioning on the GPZ head (with ZR7 cam in place).
I hope my explanation is clear, but it would be easier with the corresponding parts diagrams.


He would have used the complete head and cams but the cam stays were missing.

In any case the bike runs well, and the dyno will tell us if it is worth it.
 

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GPZ Cams

any idea as to the comparison between the stock ZR7 S cams and the GPZ cams i.e. do they provide a higher lift and/or longer dwell for "open" and is the lobe profile significantly different ?
have dropped in a Wiseco kit and am wondering if the GPZ cams will be a better "fit" in the scheme of things ?
haven't ridden the bike as yet, but the exhaust sound has changed.
[saving up for my next 'project' - a full exhaust system]
micah
Silver '02 ZR7S/Ivans jet kit/Muzzy ignition advancer/Wiseco pistons/PIAA white light/undertail hugger/front fender extender/shortened rear fender/lowered gel seat
 

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Discussion Starter · #5 ·
micah said:
any idea as to the comparison between the stock ZR7 S cams and the GPZ cams i.e. do they provide a higher lift and/or longer dwell for "open" and is the lobe profile significantly different ?
have dropped in a Wiseco kit and am wondering if the GPZ cams will be a better "fit" in the scheme of things ?
haven't ridden the bike as yet, but the exhaust sound has changed.
[saving up for my next 'project' - a full exhaust system]
micah
Silver '02 ZR7S/Ivans jet kit/Muzzy ignition advancer/Wiseco pistons/PIAA white light/undertail hugger/front fender extender/shortened rear fender/lowered gel seat
They provide higher lift AND duration.
In other words they are suitable for a 'tuned' motor. Plus they are genuine Kawasaki parts :)
 

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I think the mods sound like pro mechanic stuff to me. I do also have the entire GPZ head as well. Maybe once I am done procrastinating I will just do that.
 

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Discussion Starter · #7 ·
buster said:
I think the mods sound like pro mechanic stuff to me. I do also have the entire GPZ head as well. Maybe once I am done procrastinating I will just do that.
If you have a complete GPZ head, it's a simple job of removing the ZR7 head and installing the GPZ one.
Note that the GPZ gasket is justtrouble compared to the 'new' ZR7 gasket.

As soon as the bike is dynoed with these cams, I will post the results.
I hope that the gains will be worth it.
 
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