From Scratch

cra-z1

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Hi Guys, I have been working on a 73 Z1900 for a friend. This will be the 4th Z1 I have done for him. As the title states its from scratch. On this one we started with a rolling frame, without a title (Frame,wheels,front forks) everything else I had or is being sourced. Got the title sorted by Saints. very good service. The last Z1 I did for him we started with a set of 73 cases and sourced everything else. Lot of work but enjoyable. What else does a 71 year old have to do. Glade I don't own a TV and our town doesn't have a nudie bar.
Had the frame power coated, took the wheels apart to polish and paint things and have started to put things together. We just got a set of cases that need some cleaning before painting and the head will have all new valves/guides as it was in pretty rough shape. I had a crank sitting here which is being rebuilt by Garden Racing in Maine.



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I will also be pulling the engine on the black bike this winter to replace the cases and install rebuilt crank from Gardner. I built that bike last winter form a combination of parts from 73 to 80. It had a major problem that I thought I could fix but it didn't work as expected. I have a leak so cases will be replaced. It also has a 1000cc crank (1000cc crank is about 5lbs heavier than the 900) I had laying around that I thought I would try. I didn't like the way it ran so that crank will be replaced

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I also just got done with this 1982 KZ1100 A few months back ,waiting for the paint work to get done. I tore it apart except for the engine, cleaned everything (very dirty and full grease and oil) the pipes were pretty solid so I decided to have them blasted and high temp powder coat applied. Any of the chrome that was rusty like the brake and shift levers was given the semi gloss power coat treatment. Had to source a lot of new parts for this one. Couldn't find a rear grab bar so I got one from some Kawasaki model that was to long and narrow, cut it into 5 pieces and welded it back together and it was also powder coated. Rebuilt all the brakes, carbs wheel bearings, replaced a lot of rubber parts. It had been pressure washed I believe so rust and water intrusion to critical areas. DONT PRESSURE WASH YOUR BIKES.

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Amazing work! Why does your friend need so many Z1s?
It's a sickness, I had 6 but have received some counseling and sold 2 this year.


Wow, what a workspace!! And very nice bikes as well!

Was the 1100 the first for CV carbs on a Kawasaki 4?
I believe so on the CV carbs. I had a worn needle and jet but found a set of 83 needle and jets. Slightly different but should run good. We will see next spring.
 
Today I needed to clean the cases before painting. The cases had been blasted with I believe sand which left a greyt dust all over them including the oil passages, they also have beed sitting around for years and have oxidized. Im not a fan sand blasting. The particles can into the aluminum so after several washes with hot Dawn detergent and a brush into the oil cavities Im ready to do them in my blaster. I tape off all the oil passages and use screws in all threaded holes to avoid my media getting in the threads. I spent quite a few hours cleaning all the sand out of the holes already and dont wand to do it again. I use a Stainless Steal media, course and fine. On parts that will painted I use the course media for a good bite for the paint. The media will not shatter. I lightly blasted the inside to hopefully dislodge any sand that may have embedded. After blasting they get cleaned again in hot water with Dawn and hit the passages again. Blow them dry and put them in a 170 degree oven for a bit to make sure they are dry. I also blasted the cylinders the other day. We will be boring the cylinders before painting them.

Blasted and painted

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I decided that it would be a good time to lace and true the front wheel, I did the rear the other day. This is my set up. I use a pointer for the side play and a dial indicator for the up and down. I try to get it within .020 up and down and maybe 1/32 side to side. Have to go slow and watch both indicators. I typically get the side to side very close with a lot of adjustment left then start workin on the up and down. Took me a bit on this rim but I ended up with about .020. Had to do some loosening on one side and then tighten on the other side. It can get confusing when you are looking at the dial indicator and trying to decide do I tighten or loosen. Once you figure it out it goes pretty good. At the weld it goes another .010 but thats to be expected. I do use a torque wrench as everything gets tight. When you get it to the point where everything looks good and all the spokes are pretty tight I start to tighten each spoke 1/4 to 1/2 turn starting at the valve Stem hole. When things are pretty tight it's hard to pull everything out of wack with just a small turn at the nipple. I keep checking the indicators. 26 inch pounds is what is called for on the Z1 wheel. If I am going SS spokes 35 or so inch pounds. Tires should be here tomorrow for mounting.





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Cleaned and inspected the input and output shafts today. I disassembled the gears and didn't like the transmission that he bought. Had some rounded dogs and slots also I didn't like the runout on the shaft. So I dug out a few that I knew were better. New bearings were installed. The old ones felt ok but the last Z1 I built for him I ended up removing the engine and splitting the cases to replace those bearings I thought would be ok. Had a monstrous vibration at 3500-4000 rpm and after isolating the trans from the crank I determined it was probably the bearings on the trans.

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Bad looking gear, note the big flake of metal to the right.

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