Clutch spring interchangability

Will clutch springs from a 1000 work in a 750-4?

I know they're a different part number at buykawasaki.com, but I've seen some aftermarket springs that supposedley fit 650/750/1000.

How do they differ physically?

Are the 1000 springs bigger than the 750 springs?

Anyone?

Anyone?

Why do you even want to try it?

they fit, they are stronger.

from the gpz mod faq

I'm always looking to try something that might be less expensive so I ordered a set of racing clutch springs to fit the Kz 900/1000 (pt # 40-0445) from Schnitz Racing Enterprises (800-837-9730) located in Decatur, Indiana . $12.95 for the springs plus $3.50 for shipping put them on my door step for $16.45. These red springs measured 5% shorter than the stock GPz750 springs, but the wire thickness was 25% greater than stock. After I installed them the clutch lever felt slightly stronger than the previous $30 aftermarket spring that I'm using. The difference was noticeable ! The clutch was locked up tight in all gears and there was "never" a hint of clutch spin. I was so impressed with the clutch springs (and the cost!) after this that I called and ordered 3 more sets for the spares pile. These springs will fit all Kz/GPz/Zr 750 clutches. The stock 750 springs measure 48 lbs. @ .950" and the Schnitz "red racing springs" springs are 94 lbs. @ .950" . I find the slight increased clutch pull not to be obnoxious even for city riding with these stronger springs. The price of the springs are $13 plus shipping + handling from Schnitz in the USA. If you or anyone else from out of the USA are interested in these springs let me know and I can send them direct to you at a much reduced cost of shipping.

kzwolfsr wrote:

Why do you even want to try it?

they fit, they are stronger.

Guess that about sums it up...

I doubt they are stronger. If you look up KZ1000A clutch springs, they were the exact same springs as used on countless models from KZ650 up to the the KZ1000 including KZ750 twins, but *not* the KZ750-4 for some reason. Would they use stronger springs in a KZ650 than a KZ750-4 from the factory for some odd reason? I doubt, so the question remains, what is the difference? I doubt much of any, but just conjecture on my part. Now aftermarket springs, there will be no rhyme or reason or any real predictability. I'm just talking factory Kawasaki springs. Aftermarket very well be stronger on a KZ1000 than a 750, or the other way around. That's why I generally don't do aftermarket.

Perhaps inapplicable here, but seem to recall Z1/KZ900 owners going to higher lift cams and stiffer valve springs, and using the old stock inner valve springs as stronger clutch springs (with slightly stiffer lever pull).

Patton wrote:

Perhaps inapplicable here, but seem to recall Z1/KZ900 owners going to higher lift cams and stiffer valve springs, and using the old stock inner valve springs as stronger clutch springs (with slightly stiffer lever pull).

Now there's an interesting thought! I picked up a KZ650 head a few years ago so I have extra valve springs...