Doctorot's '78 KZ1000 build

This summer i noticed i had quote a bit of lash in the kush on the rear wheel. at least 3/8" that i could rock easily back and forth, probably more like 1/2"+ under real pressure. I bought this repro kush rubber by PMC from Webike and the fit is perfect, zero slop. I always felt like i had to be very conscious of keeping the drive train loaded, hopefully this will help with that.
 

Thanks. Good that the aftermarket is working, OEM are drying up and getting expensive. I was lucky a couple years ago and replaced mine inadvertently in my ‘78 1K disc. I was chasing a low rpm surge, before I figured out it was air leak in the carb holders I was looking to the drive train. Replaced the Cush drive, adjusting chain, looking at backlash at the counter sprocket. 

DoctoRot post=860390I bought this repro kush rubber by PMC from Webike and the fit is perfect, zero slop. 

As Mikaw said, it's nice that reproductions are available.  The cush-drive in my Z1R still feels tight, but it hadn't occurred to me until now that it might have become really hard and stiff over the years, like all of the other rubber pieces, and might not actually be doing a great job a a shock damper any longer. 

How does the new replacement feel relative to the vintage part?

Is there an easy test to measure play that would isolate it to the kush damper?

Hit the rear brake and try to move/whiggle the rear sproket by hand (in neutral). If the kush drive can move easily back and forth by hand, the rubber damper have to be replaced.

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DoctoRot post=860390I bought this repro kush rubber by PMC from Webike and the fit is perfect, zero slop. 

As Mikaw said, it's nice that reproductions are available.  The cush-drive in my Z1R still feels tight, but it hadn't occurred to me until now that it might have become really hard and stiff over the years, like all of the other rubber pieces, and might not actually be doing a great job a a shock damper any longer. 

How does the new replacement feel relative to the vintage part?

 

Better in every measurable way. PMC always makes high quality stuff. It was $105 shipped from japan the dampers for the Z1 and MKII are cheaper, came in about a week - I love WeBike.

japan.webike.net/products/22640411.html

Discovered a new oil patch on my local on ramp. Not too much damage, and most things can be easily fixed except for a scrape on the tail and some road rash on the swingarm. I rode it home. This is why you always gear up even for small errands, i didn't get a scratch. Time to make it better.

 

Ouch. I'm glad you came out of it unscathed. 
I run those same Oury grips on all my vintage bikes except the GPz. Love 'em. 

Aww man bummer, good to here your intact. Good advice on the gear. 

Damn, that sucks but this shit happens to the best rider (me too). Time to think about some crash bars/pads?

Glad you are good and healthy after it , yep it’s the short runs that are the dodgy ones, in the summer I’m all bike, in and out of work and it’s a mine field out there. All will polish out and leave cool scars, especially that moriwaki points cover…

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Damn, that sucks but this shit happens to the best rider (me too). Time to think about some crash bars/pads?
 

I think i will at the very least make some axle sliders since i have a hollow axles. That would have prevented all the damage to the swingarm which is a big ol' bummer. The tubular crash bars/cages that i've seen on KZs are really unappealing to me on a custom like this. They look OK on a stockish bike. The sliders that Sanctuary/Bulldock use on their builds don't really seem like they would do much. Not sure what to do yet.