The Friendship Bike - NobleHops restores a 75 Z1

Hello!

Second post here, glad to be here.

I posted a new member intro elsewhere, so let's get to the goods, namely my Z1. I am about to restore it, and I will probably need some help along the way. In return for your kindness and contributions I will try to contribute some entertaining and hopefully useful content to go along with my bloody knuckles and tales of excessive chemical inhalation. Square deal?

Here's the bike:



That's a 1975 US-spec Kawasaki Z1 900. I bought in San Jose, California a year or so ago, and drug it here to Arizona when we moved here last summer. We're calling it "The Friendship Bike" because I'm restoring it for fun and then I am shipping it to my friend Pius in Switzerland. I met Pius in 2011 on an Edelweiss tour of South Africa, and we've since toured the Alps and Dolomites together, plus a giant loop of California last year. My hope is to finish this restoration in time to ship it to him before our next adventure this July in Europe.

Very laudable...welcome to KZR...I wish I had a friend like you...

So here's a better overview of the bike and the project.

It's a 75, was lightly molested by some or other of the previous owners. It's missing the stock turnsignals and mirrors, rear chrome fender. Has a Dyna ignition and coils, badly installed, coils are shorting madly when the bike is running due to some really poor wire construction. Has a period Kerker 4>1 that was repainted at some point, it's solid and looks good, but I can't get it into Switzerland with that on it, so there's a Doremi repro exhaust in the attic that will go on when we're done. Wiring seems "ok", there's some weird vampire tap under the tank doing nothing that I can see, and the starter cranks slowly even with a full battery, so that may need rebuild in addition to cleaning and renewing all those connections.

Has pod filters, will be returning to factory airbox and filter. Have not determined what jets are in it, carbs are on the bench though getting a mini-cleaning while I assess the condition of the bike. Fuel lines were cracked and leaking, carbs leaking and plugged, petcock leaking, tank mildly rusty. Missing the centerstand spring. Seat recovered. Single disk front, will be converting to a double.

Plan of attack is to quickly get it running as well as I can without spending a ton of time on it to assess the health and condition of the engine and transmission, see if it needs to come apart. I did a cold compression test yesterday, found the following values:

1 - 125 PSI
2 - 140 PSI
3 - 125 PSI
4 - 125 PSI

Cleaned and replaced the plugs and was able to get the bike running on three cylinders for a few minutes, discovered the bad coil wire, and repeated the compression test - everything but #1 went up about 10 PSI. I removed the carbs and float bowls last night, blasted the jets clear and gave the float needles a quick wipe. cleaned the nasty pod filters and left them to dry overnight. Will set the float heights and reinstall today.





As above, today I am going to recrimp the sparkplug wires and see if I can run it a bit longer, repeat the compression test and see if it's smoking to any great degree, see how noisy the cam chain and head is, how it shifts, etc. Then I'll make the call about going into the engine. It is showing only 6700 miles on it, so unless that's BS, it may not need anything other than a good servicing.

The chassis will get the full teardown for sure:

Rebuild all brake calipers, new pads and parts, brake lines. Converting to dual front disks. Rotors will be sent to my pal Tom at TrueDisk for resurfacing.

Fork will get teardown, replace the seals and wear parts, new springs and some flavor of cartridge emulators, either Racetech or Ricor.

Steering head bearings will be replaced.

Swingarm bushings/bearings will be replaced and I'll put a modern zerk fitting on it while its apart.

Planning a set of Hagons for the rear, sprung to match the front.

Wheel bearings will be replaced.

Wheels will be re-laced, probably with new rims.

Frame and swingarm will be refinished, still mulling paint or powdercoating for that.

Anything steel will get replated, most anything alloy will get vapor blasted, and anything chrome will get replated or replaced.

Seat will be recovered or replaced.

Gauges will be replaced with repros, in KPH.

The bodywork is all going to be replaced with the reproduction stuff that Z1parts.net and other vendors sell. We're returning the bike to a correct factory color scheme for a 75 - blue.

So that's the overview. More later after I see what I learn today.

Mcdroid wrote: Very laudable...welcome to KZR...I wish I had a friend like you...

Thank you McDroid!

welcome can't wait to follow along :evil: !

leon

The carbs aren't 75. You may have to replace the valve guide seals being they are so old. If you want to keep it stock, re-chrome the wheels. They are numbered as well as other parts.
Steve

swest wrote: The carbs aren't 75. You may have to replace the valve guide seals being they are so old. If you want to keep it stock, re-chrome the wheels. They are numbered as well as other parts.
Steve

Steve, please tell me more about the carbs if you don't mind. Took a fast look for some ID on them but didn't find it, I did find my way to this page, which was awesome, but I haven't studied it yet:

www.wgcarbs.com/index.php/using-joomla/e...ategories/92-z1-carb

Thanks for the advice re the wheels, much appreciated, and PLEASE, keep it coming, I need the help of you guys that know these bikes, big time.

OK, I ultrasonic'ed the jets yesterday and set the float heights to 24mm, put them back on. Going to fire it off the aux fuel bottle shortly and see what I can learn about it. Will report back.

These are my old 28mm Miks. I should have taken better care of them. The stock 28's were hard to keep balanced. But ran good even with a 1015 up grade.
Steve



Those might be 29's or 26's. I can't tell.

The Old Kaw Man on line is a good place for vintage Kaw parts and information.
Steve

Just measured - they are 26s. I will look a bit harder for markings - it would be good to know what they are correct for.

Steve, they have 120 main jets in them now and 17.5 pilots. It's currently got pods and a Kerker 4>1, but I will be putting a stock airbox back on plus a repro stock exhaust. Would you hazard a guess about what a good starting point might be for the main jet? Seems like that pilot jet is a stock size from the little bit of reading I did on that other site, but if you've got thoughts about those too , I'd be very interested.

The pilot jets are correct and the main should be 112.5 but the 26's were on the KZ 900 and KZ 1000. Too bad they're not 29's. They were the hot setup for the bike. You can get stock 28's if you want to keep it stock. That will depend on how much has been changed. Z1E has a chart of codes. I'd compare the parts to see if it's a clone or not.
Steve