'76 KZ900 (ZRX1200R) Build

Doug,

Thanks for the kind words! I just am choking on the bit to get the wheels fitted. Needing to figure out how to machine the hub now that it assembled. Otherwise I need to offset the front sprocket an additional 3/8" which means HUGE frame notching!

Cory

Can you mount the wheel flat on a a rotary table mounted on a vertical mill? I know it may not be as easy as chucking up just the hub in a lathe, but its got to be easier than unlacing, lacing and retrue'ing the wheel.

Later, Doug

Thought about that, but I don't have a rotary vise.... Ugh...

Cory

531blackbanshee wrote: here is how sanctuary processes the chain line.

hth,leon

Leon,
Any idea of the depth of the clearance cut and what GA material they are welding back in?

P.S. Are these pics of 2 different frames?
Pic #1 has a welded in rear motor mount I was looking at real close because of how it mounts to the frame.
(What frame is that? It's not like my 74 Z1 900 or 78 LTD1000)
Pic #3 doesn't have this mount.

Also pic #2 has the chain clearance cut higher than pic #3 under the swingarm.

I have always wondered if that type of mod weakens the frame at all?

My uneducated guess is side to side could be compromised a bit and vertical would be more rigid. I am curious about it as well.
Wayne

79MKII wrote: I have always wondered if that type of mod weakens the frame at all?

That's nice work. Both the build bike and the Sanctuary pics. I love the tensioner you made for the alternator. That's art!

sorry i can't answer any questions "for sure" as i have never done this mod,and the pics are from sanctuary.
but,
you can bet they wouldn't be doing the mod if it compromised anything .
every bike they build with modern wheels and tires has this mod.



from my own mind you have created more structure there now.
it is no longer straight runs of tube joined,it is now in effect a bridge.


leon

Thanks for the pics again Leon. Since I don't want to really disassemble the wheels and cut the hub as I don't have access to a lathe with that much swing...Going to order up a D&G Chassis Bearing Support plate and a custom offset front sprocket. I was thinking about using a rectangular tubing to "box in my notches" and run the chain through them if that much clearance is needed. I believe from my measurements, to correct for the new wheels, I need 3/8" (.375") additional offset. No I also want to correct the factory 12mm offset built into the wheel/swing assembly on the ZRX1200, so I may try to perfectly center up the rear wheel and correct that while I am at it......

Cory

Back in 2009 I took a welding inspector course for non-destructive testing. Well, we also learned destructive testing :laugh: - I took several samples of Z1 and KZ 1000 frames. Guess what? The metal is crap, and they use seamed tubing. In the pics above, homey strengthened up that area of the frame far, far stronger than it was ever before, just by using modern mild steel. I xrayed all the intact frames, and we did full on electron microscope and spectrometer testing on the bits I cut off.

I could not believe how crappy the metal was, very high silica content, basically pot metal. It does not even come close to making current spec. The genius in engineering for Kawasaki was in the direction they placed the seams (they definitely oriented the tubing in a specific way, on every bike that I tested from 75-80. )and made this metal work.

Don't sweat it man- your frame is now stronger than ever.

CruisingRam wrote: Back in 2009 I took a welding inspector course for non-destructive testing. Well, we also learned destructive testing :laugh: - I took several samples of Z1 and KZ 1000 frames. Guess what? The metal is crap, and they use seamed tubing. In the pics above, homey strengthened up that area of the frame far, far stronger than it was ever before, just by using modern mild steel. I xrayed all the intact frames, and we did full on electron microscope and spectrometer testing on the bits I cut off.

I could not believe how crappy the metal was, very high silica content, basically pot metal. It does not even come close to making current spec. The genius in engineering for Kawasaki was in the direction they placed the seams (they definitely oriented the tubing in a specific way, on every bike that I tested from 75-80. )and made this metal work.

Don't sweat it man- your frame is now stronger than ever.

That is great information, first hand too. Thanks for sharing!

79MKII wrote:

CruisingRam wrote: Back in 2009 I took a welding inspector course for non-destructive testing. Well, we also learned destructive testing :laugh: - I took several samples of Z1 and KZ 1000 frames. Guess what? The metal is crap, and they use seamed tubing. In the pics above, homey strengthened up that area of the frame far, far stronger than it was ever before, just by using modern mild steel. I xrayed all the intact frames, and we did full on electron microscope and spectrometer testing on the bits I cut off.

I could not believe how crappy the metal was, very high silica content, basically pot metal. It does not even come close to making current spec. The genius in engineering for Kawasaki was in the direction they placed the seams (they definitely oriented the tubing in a specific way, on every bike that I tested from 75-80. )and made this metal work.

Don't sweat it man- your frame is now stronger than ever.

That is great information, first hand too. Thanks for sharing!

NP- least you now know why these things have such flexy frames stock LOL.