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Discussion Starter · #1 ·
As if I didn’t have enough projects already. I found this on CraigsList. (Note to self; delete CL and eBay apps ASAP!)

It looks a lot rougher than it is. It’s really solid, just not very pretty….or clean. The Kerker has surface rust but only a small flat spot underneath. The motor rotates with the kick lever and has a bit more resistance than my 1000 does. The black cylinder block and cam cover makes me wonder is there’s been some nice internal work done. Choke plungers and slides move easily with great snap-back. Mice decided to camp out in the battery box but overall not bad.







Later, Doug
 

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Discussion Starter · #3 ·
After raiding my mental inventory of spares, I’ll need to buy radial caliper adapter brackets, a gas cap, adapter plate for a Pingel fuel tap, steering bearings, maybe an offset front sprocket and some other odds and ends.

The hardest fab part will be narrowing the swingarm and getting a proper title. I might have to go through the Vermont route since I did get a bill of sale.

Later, Doug
 
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Discussion Starter · #5 ·
Ordered up some parts. Grabbed a used gas cap from eBay. Also scored a pair of Galfer wave rotors with the correct diameter of 300mm for $75/shipped!! I found my old Pingel adapter plate so I can mark those off the list.






Later, Doug
 

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Discussion Starter · #7 ·
The bike didn’t come with keys so I thought about having a key made until I found out A) the ignition switch and seat lock were different codes & B) the switch that was installed has a 6-pin connector and no 7th wire because the 79 has an extra wire compared to any other year. So I ordered a complete used matching lock set for a little less than 1/2 of what I paid for the entire bike. Getting two master keys and two copies may not have been much cheaper anyways.

I’ve pretty much decided on using a spare set of ‘76 900 VM26 carbs for several reasons: I have them and I rebuilt them before putting them away, the current carbs need rebuilt plus they have an accelerator pump, and I’ve read the 26’s offer more performance like the 29’s do on the 900/1000s. The last one I’m not so sure about but might as well try.

Later, Doug
 

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Discussion Starter · #8 ·
I had some time so I pulled the Zx6R front end down from the rafters. Center of axle to top of fork leg is 30”. Stock Kz forks measured 29-1/4” with weight on them. I’m going to lose ground clearance from the swap from a 19” to 17” wheel but hopefully none due to the fork length. I had a stock Kz900 stem that I was going to use on a dead project and compared it to the Zx6 piece. A stem swap is going to be a must. The Kz stem was welded to the lower clamp. The Zx stem is pushed in and held with a retaining ring. Both stems look like they’re 28mm OD. (I know the one pic shows 27.92 but hard to hold a camera and caliper too.)




Later, Doug
 

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Discussion Starter · #9 ·
After more thought, a simple stem swap from the Zx to the Kz stem isn’t going to work as well as I hoped. The Kz’s stem is the same 28mm diameter through the triple clamp but increases to 30mm above. This means I can not push it up through the triple to install it. I thought about turning the bearing journal down to 28mm, but there’s no lip around the bottom to retain. Then I thought some more… welding a bead all the way around and then turning it to machine a lip could work for the bottom. Then my attention turned to the other end of the stem. The Kz and Zx stem are vastly different as well.

Again, I mentally raided my parts inventory and remembered I have a triple clamp set from a Zx6E. I bought it to use on my Gpz about 10 years ago. I compared the two Zx stems and think I have a winner.

Kz…Zx6E…Zx6R. All stems are aligned at the bottom of the lower journal.


The two Zx stems: upper end.


Turning down the 6E’s 30mm lower journal to 28mm. This will match the 6R’s lower clamp’s bore.



I finally ordered a much needed boring head for my mill. I’ll need to to sink the 6E stem a bit further into the R’s clamp since it’s thicker and I need to keep the lower bearings journal location the same.

Later, Doug
 

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Discussion Starter · #10 ·
I received in the matching lock set yesterday and installed both the ignition switch and the seat lock. I got the steering lock and gas cap too. The old Kz caps don’t have tumblers so any key will open them. I guess I have a spare now. I may swap out the steering lock. I will need to machine a slot or hold in the Zx6E stem if I want to use it. So I’m still mulling that over.

Since. I had an switch that worked, I hooked up a spare battery and hit the start button. What do you know….it cranked over! The battery was sort of week, but it worked.



Later, Doug
 

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Discussion Starter · #11 ·

Let’s see if the link works….

I cleaned and gapped the points, removed the carbs and sprayed some starting fluid in the intake ports and…it lives!

I also filled out all the forms and sent a check to the Vermont DMV yesterday. I’m trying to use their system to register it for street use.

Later, Doug
 

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Discussion Starter · #12 ·
I should have been doing other tasks in the garage but couldn’t help it as I’ve not machined anything in a bit. I was having chip withdrawal.

I machined my top clamp to remove the ignition switch lugs and add holes in for my bar risers.













Later, Doug
 

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Discussion Starter · #13 ·
On to the lower triple. The Zx6r clamp is a bit thicker than the 6E clamp. This means that the stem needs to be pushed further through the R’s triple to have the same bearing journal exposed. In this scenario that means the R’s triple needs bored 3.5mm deeper.


I finally ordered a boring head for my mill and couldn’t wait to use it.



I popped the stem in the freezer overnight to chill a bit. I don’t have a press so I used a BFH and a piece of alumiyummy bar to protect the stem.



And voilà!




Next stop is conversion steering bearings, fork stops and gauge mounting solutions.

Later, Doug
 

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Discussion Starter · #15 ·
I just idle through your stuff... love the setup of the shop
Thanks man!

I just had a 100A sub-panel installed on Monday with a dedicated 50A 220V receptacle for a welder. I’ll finally be able to start practicing with my TIG. It’s a 110/220 unit but the lights dimmed when I turned it on for testing 110V.



Later, Doug
 
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Discussion Starter · #17 ·
are you pulling power off of your main house panel for that 100A for your shop?
I am. I had 4 estimates from electrical contractors for the work and none said that a separate meter was required. I know for sure that two mentioned a 100A breaker in the main box to feed the sub-panel. :dunno

Later, Doug
 

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Discussion Starter · #18 ·
I cleaned up the rotor side of the rear wheel. Started with a buffing pad in a hand drill. It was the wrong item for the job so I finished cleaning and polishing it by hand. 40mins later and it’s not perfect but definitely more presentable.



I had a Driven 220mm wave rotor left over that I’ll be using. And I found a fluke of a deal on a brand new Vortex aluminum sprocket for $14.54 on Amazon!! I need to find some prettier 3/8-16 fasteners for the sprocket side. The current ones are yellow-zinc plated and look like they came off a farm tractor.




Lastly, I thinned down the LH spacer that came with the PM wheel by 3.5mm. The wheel slides in perfectly and without slop.







Later, Doug
 
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Discussion Starter · #20 ·
Realy need to get myself a mill. What make and model do you have? Nice conversion job. How much thickness is left under the head of the studs?
My mill is a “Select Machinery” version of an Asian 6x26”. Jet, Enco, Grizzly, HF, etc. all had versions of it at some point. I think it’s the smallest knee mill you can get. Any smaller and they are column mills.

Thickness of the triple is about 1/4”-ish thick.

Later, Doug
 
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Discussion Starter · #21 ·
I rolled the 650 backwards onto my lift and started disassembling the front end. It took me about 30mins plus another 10 to knock the old bearing races out.




I made some mockup steering bearings using some Delrin. It’s not cheap but easier and quicker to machine than aluminum.



Next up was installing the triples and lower legs. There are not a lot of threads exposed after installing only the bottom locknut. It will need massaging later but I can make it work. Plenty of thread protruding through the upper clamp though.




Back on two wheels.




Next stop is solving the steering stops. I can either use the Kz’s boss and add to the lower triple or use the lower triple’s lugs and weld a plate to the frame.



Later, Doug
 

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Discussion Starter · #22 ·
Knocking down the frontend to-do list. Front fender, gauge mounts, steering stop, brake lines, and headlight mount still remain, yet.



Since the front end is sorted enough to roll the bike, I spun it around so the swingarm swap can be tackled.





My biggest hurdle will be the swingarm pivot width. The Kz’s is 229mm….the Zr7 is 244. I drew up a diagram to help visualize things. It seems as if some sparks are going to fly for this.


Later, Doug
 

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Discussion Starter · #23 ·
Warning…LONG 2-part post ahead.

Pulled the old swingarm out. Surprisingly, the pivot bolt slid out very easily. Just as I found on the web, the stock Kz pivot width is 229mm..


Knowing that I need to remove about 7.5mm per side, I cut about a 5-6mm sliver off of each side. This dimension, along with the saw blade thickness, gave me just enough material left to flatten and smooth out the rough edges left.





Then I turned up a left mockup bearing and a right side spacer since the Zr7 uses a 20mm axle compared to the Kz’s 16mm.


Time to slide the swingarm in to see if it would fit and if there were an interferences. The left side passenger peg bracket is close but has enough clearance.



I offered up the wheel to check for offset and the chain run. Turns out my right side spacer was ever so slightly long.




Went back and took about 1.5mm off the right side spacer. The tires aren’t perfectly aligned but “good enough for who it’s for” as my dad used to say.



A check to the chain line was next. It turns out my 5/8” offset sprocket is about 1/16” too far offset, which isn’t all that bad of a problem to have.



I threw the old chain on to check frame to chain, etc clearances. The 18T 530 sprocket is definitely the largest one that can fit. I’m going to have to remove the nuts for the footpeg studs as well as shorten the threads.



To be continued…

Later, Doug
 

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Discussion Starter · #24 ·
Hung the shocks to looks at angle, lower mount locations…




And an obligatory 3/4 view.


Last thing was to check rake, trail, swingarm angle and wheelbase. With a 23.1° rake and the Zx6R’s offset, trail is around 95mm. The Zr7 arm is almost 2.5” longer than the Kz’s. This means the WB is 57” with the axle all the way forward. Swingarm droop is 7.5°. Note: all these numbers are with the rear suspension fully supported.




Later, Doug
 

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Discussion Starter · #25 ·
Started digging around for more geometry information. Found a small nugget on AC Sanctuary’s website and another small piece of the puzzle on KzRider. These specs apply to the Z1/Kz900/1000 but the Kz650 is of similar design and geometry so maybe the same is applicable.



I put my shocks in the general location of where I want them and lowered the rear support that was holding the frame up. The bike sat on its own for the first time. This allowed me to find the true rake and get a close measurement for trail.






Comparing AC Sanctuary’s info and the FSM for the donor Zx6R, I’m sitting pretty close to where I want/should to be. I measured an offset of 42mm for the Zx6R triple clamps.


Later, Doug
 
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