'78 KZ1000 makeover

Here comes Murphy again! While I was splitting the cases, and removing the outer crank main bearing bolts, 2 of them sheared off. Great. I tried welding nuts onto the exposed bolt ends (they were flush with the upper case) but I would just shear those off again. I tried penetrating oil with the case heated up, and I tried left hand drill bits and GENTLY tried an easy out (like THATS gonna work after shearing off 10 welded nuts). I reserved myself to the fact that I did not have the tools to remove these bolts, and I either had to find someone who did or find new cases. A friend and a local bike shop owner referred me to J&P Deburring in Chatsworth California. With an EDM machine and my wallet $40 lighter, the bolts were gone. They also told me they could make my cases look new again, and I said "ok, show me what you can do". And the following was the result for the case and oil pan.

I don't know what these engines looked like new, but I was VERY pleased with the finished product. The cost? $40 for the cases and oil pan!

They could have my 40 bucks. Roy

What did they do to them???? :blink:

roy-b-boy-b wrote:

They could have my 40 bucks. Roy

no shit!!!! and what is their method?

I do not know the exact method, but I will find out. I want them to do my cylinder and head also. What I do know is it was a three step process with 3 different blast media. Two of the steps were glass bead and plastic media, I THINK. I'll find out next week and let you guys know.

KensKz - exactly which bottom end upgrades are you refering to? I asked APE to lighten and weld my crank, but they don't lighten KZ cranks and their welding guy dropped off the face of the earth. The told me to contact Gardner Racing Cranks, as he is one of the few that still work on these press fit roller bearing cranks. I am still contemplating having the tranny back cut, but you can get into some serious money when you start upgrading gears, shafts, shifts forks and the like Where does a guy put his foot down on a 1075 street build? As BadDad has noticed, I'm not new to modding, but I am not familiar with all the idiosyncrasies of the KZ...yet. Larry Cavanaugh was kind enough to talk to me about what I wanted out of my engine and gave me an engine combo he felt would make me happy. A street port job, the Wiesco 10.25:1 1075cc kit and Cam Motion Z1 grind cams fed by a quartet of Kiehin 31MM CR Specials. Larry also told me that I did not need to weld my crank with this engine combo. At the same time, the last thing I want is to have a problem with a fresh engine and split the cases again.

i have heard people say that they have seen stock motors slightly twist a crank out of place. I contacted ape about my crank quite a while ago and got the same story. I called up Gardner racing, and he was VERY good to work with. Great guy that did a damn great job. I am very satisfied, and i think it was right around $200 total including mailing that heavy bastard from SD all the way to maine and back

jordan wrote:

i have heard people say that they have seen stock motors slightly twist a crank out of place. I contacted ape about my crank quite a while ago and got the same story. I called up Gardner racing, and he was VERY good to work with. Great guy that did a damn great job. I am very satisfied, and i think it was right around $200 total including mailing that heavy bastard from SD all the way to maine and back

You know, I think I read almost that exact same quote from OMR's experience with Stan Gardner. I had originally thought that if I was going to go through the trouble of sending a crank out to get trued and welded, I'd pick up a Z1 crank. Now I'm not so sure the extra performance of a lighter rotating assembly is worth the extra cost.....Any thoughts fellow hot rodders?

i have asked this question a few times also, and pretty much arrived at that the difference in cranks isnt much difference. Both have slight advantages, arent heavier cranks supposed to be a little torquier from the larger rotating mass, while a slightly lighter crank will wind up faster? The only crank i have been told that would be worth swapping to is the big pin cranks from an mk2 or z1r. Oh ya, when i got my crank i also got a book with gardner's signature on the page wiht his ad

It seems as though a call to Stan Gardner is in my near future then. What is the prevailing opinion on replacing/upgrading the clutch hub backing plate springs? Same question on the transmission bearings. They seem tight, no play, roll smooth sooooo :huh:

can you spin the springs in the clutch hub? can you wiggle them? If yes, i would replace them. I duno how often people replace transmission bearings but mine seem perfectly fine and i will be reusing them. Hopefully somebody else will chime in on this