Fish's 1992 750C Engine Rebuild and Other Goodies

Document your ongoing rebuilds and restorations here
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

A few other bits:
I wish I had taken pictures of the fuel float gauge. It had rusted out the contact that is attached to the wrapped wire. This was from the float sitting for years with fuel in tank. I cleaned it up, and cut a new contact and re-soldered the tiny wire. It was a real pain in the ass, but better then spending $120 for a new float. Although, considering all the other expense, that was small potatoes. I was just proud of myself for fixing it.

I polished some aluminum.
Polish 1.png
Polish 2.png
I had to order a new top run for the front brake line. The new handle bar position required a shorter run.

I took apart the carburetor to clean it up. I had a carb service done when I first bought the bike. So it was pretty clean, but I did end up fitting new o-rings to the air and fuel fittings. One of the pilot jets was missing its o-ring and washer, or maybe they fell on the garage floor and disappeared. :( I had an o-ring, but needed to order a washer.
Carb Clean.png
Things left to do:
- I am waiting on new cable parts to complete all new runs. The new handle bar position and controls required new cables.
- I have parts to service the front brake calipers.
- Need to set the new chain. Turns out the output shaft of the 550 and front sprocket lines up perfectly with the back sprocket. Checked it with a laser. No offset sprocket needed.
- Ordered new spark plugs.
- Once carb is back together, I can run the fuel and air system. Dialing in the carb is an x-factor for sure.
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

So, I finally got to point where I could start this bike. Pushed the start button, nothing. First thing I did was pull the starter. Turned out I had the plastic piece that holds the positive brushes was backwards. Which meant the positive bolt was touching the casing. So I got it back together and bench tested it. Installed and still nothing. Turns out bad battery. Fixed that. Then no gas in the bowls. After checking the petcock and then sucking on both the fuel and the vacuum line at the same time I got a mouthful of gas. Gas is good. Then I check spark. No spark. Realized I didn't hook up +12V to the coils. Diagram issue. Now I have spark and gas. Pretty sure air is okay. Engine will not run. What should I be looking for next? Note that all of my security and safety features are disabled.
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Richard
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Location: Zeewolde NL
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Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Richard »

Been reading this one for a while only to find its lacking the end, did it start or what?
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

Obviously, I have not posted in awhile. I had to take a break from this project lest I lose my mind. Here is the short story. I got the engine all back together shortly after my last post. I attempted to start it up and was having fuel flow issues. I ended up spraying fuel directly into carburetor 1, and I did get the engine to run on that single cylinder as long as I fed the carburetor. As I was testing the motor with the spray system I heard a clunk and the engine seized. My worst fears had been realized that something had been put together wrong. To avoid being too upset I gave up for awhile. About a year went by. Then I decided to spend some dollars and give the bike to a shop I had luck with before. Unfortunately, they did not take on project bikes until winter for obvious reasons. So I waited until about last October and gave them the bike. This about doubled the cost of this project, but I felt it was worthwhile to have professionals put the engine back together. Turns out I had installed the starter fly wheel pin in backwards and it fell out causing the engine seizure. Always something. Fast forward 2 years later. I got a call a few days ago that the mechanics felt they went as far as they could go. The good news was that the bike was running. The bad news was:
  • 1. The horn honked when the bike revved above like 4000 rpms. An electrical issue which I figure I can solve.
  • 2. The front master cylinder was not holding pressure and actuating the calipers sufficiently. Okay. I had purchased a cheap after market master cylinder. My fault, new cylinder will solve the issue.
  • 3. The carbs are getting gunked up maybe because of old fuel they were using from the tank. Okay, take carbs out and clean them. Doable.
  • 4. They couldn't solve a clutch issue. The clutch pin kept slipping off the clutch rod. We figured it might have something to do with the modification of the clutch basket to accept the shorter output shaft of the 6 speed transmission. I had placed a bushing on the clutch pin, which you can see in the pic, to keep the pin from falling back into the basket hole. I figured the pin is just too short. I need to machine a new clutch pin with a longer stem. Here is a post in another forum about this particular issue. https://kzrider.com/forum/2-engine/6074 ... =24#842969
So I get it back home and start it up. Sure enough it runs. Sounds great, really great. A really happy sound! I figure I am on my way to a ridable bike in a few weeks. Yes, the clutch pin had once again slipped off the clutch rod. I'll take it apart and see what is happening. I place the bike in spot in the garage where I can work on it, and I just wanted to hear it run one more time. Then, as it is running I here this tinkling crunching sound which at first sounded electrical in nature, like something wholesale burning up. I turned it off immediately. I didn't see anything or smell anything, so I restarted it. Sounds good, then again that same sound. I turn it off and inspect the bike. I see a hole in the clutch cover and realize something bad has happened with the clutch. My first thought was that some pieces parts broke off and got inside the engine once again destroying all the work the shop had done. Thousands down the drain. New low. So I drain the oil, take off the clutch cover and find that the clutch pin had broken. The clutch rod was also destroyed with a nice gouge in it. I had to flatten out the gouge to remove the rod from the cover. I think I recovered all the pieces. What I was hearing was the broken end of the pin rolling around inside the clutch cover. I don't think anything ended up in the engine. HOPEFULLY. I will drop the pan as well and make sure there is nothing else. Now, part of the issue here is that I think the shop mis-installed the clutch pin in the first place and it was somehow putting too much pressure on the clutch rod causing the degradation of the rod and bending of the pin. BUT because this involved a modification, there is really no going back to the shop for help with this whether there was culpability on their part or not. It could just be my fault with the bushing not allowing the pin to re-seat into the hole. So I hope, that as it stands, I am only out the couple hundred bucks for the cover, pin, and rod. Once I get those parts I will figure out next steps.

Anyway, that catches us up. MAYBE, I will get this thing running, but at this point, I feel like this is an albatross that doesn't want the bike to sail, again, ever. I could have bought 3 other bikes for the money pit that this thing has become. C'est la vie.
Hole in Clutch Cover 1
Hole in Clutch Cover 1
Broken pin and rod
Broken pin and rod
Hole in Clutch Cover Inside
Hole in Clutch Cover Inside
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

While I am waiting on new parts, I was wondering if someone could help me out with my brake issue. The mechanics said the master cylinder was not really working properly with the calipers. Doing some research, I think it is because the cheaper after market levers are 12.7mm or 1/2" bore. Which could have an issue with the dual calipers on the Zephyr. The problem is when I look around there is almost nothing out there with a 5/8" or 16mm bore with a matching clutch lever for these bikes. I really do not want to make the OEM levers work as I would have to change a couple things to fit them properly with this build. Plus the clutch side was damaged previously, and I would have to get a whole new set up. Getting Kawasaki OEM parts is real hit or miss these days. Could be a month. Could be a year. I found this, but I don't know whether to trust it. https://alexnld.com/product/22mm-7-8-in ... reservoir/ Any ideas?
Stereordinary
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Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Stereordinary »

I can't really answer your question, but I do remember a thread on this subject over on the ZRXOA.
A breeze from the west.
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

Here is short vid of what happened when I bled the calipers with a pneumatic bleeder. Right caliper is good, but it looks like air is being introduced into the left caliper somewhere. I worked on this for about an hour dumping over a quart of fluid. I even bled the calipers the old fashioned way, but they just won't hold pressure. I can't see air coming out when I do the brake hold method, but I can't build up very much pressure. There is some pressure, just not a lot. https://youtu.be/O1X7XHx7RpE

I could not get the youtube code to work.
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Richard
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Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Richard »

My guess is the there's air being sucked in at the left caliper, not from the system but somewhere into the caliper itself. Were all threads o.k. and did you use new rings when you reassembled this calliper?
Last edited by Richard on 01 May 2022, 22:37, edited 1 time in total.
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

Richard wrote:My guess is the there's air being sucked in at the left caliper, not from the system but somewhere into the caliper itself. Where all threads o.k. and did you use new rings when you reassembled this calliper?
So, I hooked up my old master cylinder to see if It had the same issue and It did. Considering the money I paid to the mechanic you would have thought he would have checked the calipers. I took the left caliper off and it needs a rebuild. I rebuilt the back caliper 3 years ago but not the front ones. I have all the parts. Once, I get it back together, I'll report. Thanks for the info.
Fishrider
Posts: 112
Joined: 24 Mar 2018, 18:11

Re: Fish's 1992 750C Engine Rebuild and Other Goodies

Post by Fishrider »

I rebuilt my left caliper. It must been leaking somewhere because paint was being taken off the outside of the caliper with brake fluid. I cleaned it up and installed new rings and such. Turns out I think I had two problems. The caliper worked great and I got good pressure with my old master cylinder, but the new one just would not build pressure. So I have ordered a new master cylinder with the correct bore, and hopefully that will solve the issue. If you are wondering why I am not using the old set up, its because my clutch lever is broken, and the button control I have on the handle bar won't fit the larger master cylinder.

I am still working out the clutch release issue. The guys on the KZRider board have been helpful. Hopefully, I can find some resolution soon, and get this girl on the road in a couple weeks or so.
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