KZ 650 Shim Under Buckets

[Tom Ewig]

I have a complete set of KZ 650 shims, buckets, and retainers. My question is are these ok to use in my 1000 motors with no problem or do I have to go out and buy all the after market stuff

[sonicrete]

Want a straight answer The design is the same as you use on a Z-1/KZ. The problem is some stock 650 buckets were heat treated incorrectly and broke. The shims are changed to different thicknesses to get correct clearance but are the correct ones.The stock retainers are usually replace with aftermarket aluminum or titanium for a weight savings/performance gain. Nothing like a straight anwser.

[Tom Ewig]

Thanks, that all I ask is a straight answer from somebody who knows what he is talking about. Has anybody used these with success

[BillRobinson]

Tom,


As far as my experience goes, the stock stuff is as good if not better than the aftermarket. The only exception is the weight of the stock vs. the titainium retainers, and the stock ones are probably stronger. Also check the installed spring height. If I remember correctly, it is slightly different but nothing that can't be adjusted.

[Tom Ewig]

Thanks Bill, thats what I think also. Stock stuff is generally better then aftermarket pieces in most cases. If the buckets lasted 10,000 or 30,000 ,miles in a street bike why wouldnt they last in a dragbike The weight does concern me a bit with life of the rest of the valve train, how much more do these weight then SOB

[BillRobinson]

My guess would be about 1-1/2 times the titainium ones, but not certain. If you're not using giant cams, I wouldn't be terribly concerned. Just use good quality springs.

[sonicrete]

The stock 650 bucket is similar to aftermarket. I have personally seen stock 650 buckets break,it makes a real mess out of the head. In the amount of years gone by the bad ones have probably already broken. Get a good set of springs.