misfiring on right cylinder ('83 KZ750K1 LTD TWIN)

Okay, I've been posting on here for about 2 weeks now with various issues, in various sub-forums.

I bought the bike for 300, figuring it may be a turd or may be a (relatively) easy fix. If a turd, I would just turn around and sell it again and if i lost 100 bucks on it, hell, it was a gamble to begin with. If it worked, hell, I've got a fucking motorcycle and I LOVE motorcycles!

So, I cleaned the hell out of it, replaced the battery, replaced the plugs, removed the rust from the tank, rebuilt the petcock, changed the oil (really just added some, there was almost nothing in the crankcase) took the goofy fairing off, removed, dissasembled and cleaned the carbs and put em back together and threw em back on, and after it wouldn't spark, checked all electrical components (at least the ones going to ignition).

You can only polish a turd so much...

Earlier this week, after all that hard work was done, I got the bike to start, and she sounded GREAT, both cylinders firing, firing sounded in sync. The only issue when I first started it, was it was smoking on the RIGHT SIDE exhaust.

Then, I had to work, and i work 5 days on, 5 days off, and i work 12 hour shifts those 5 days, so I didn't try it again until a day or two later, and it didn't start at all!

I figured either the engine was flooded, or she stopped sparking again...

I did various things to try and correct the issue. I thought it was flooded so I removed the plugs and used the kickstart to try and cycle some of the (hypothetical) gas out, and checked the spark (it was sparking just fine, shocked me good)

So, after I was well and irritated, and after It NO GAS seemed the culprit and someone on here suggested i take em off and go through them again, last night I went through the fuel system again, all of it. Tank, petcock, carbs, etc. Started at ~3 am my time, and here at 7:30 I sit and post here.

the only thing I noticed when I was putting the carbs back together, was that the (and pardon my lack of proper names) brass cylinder thing that has a pin in it that is positioned perpendicular to the air flow, the one on the right side (the side that is now misfiring) was having trouble to go back to the "down" position. I checked the diaphragm and the spring and after mucking with it for about 30 minutes, i got it to seemingly work OK. OTher than that, the carbs looked like they did after I cleaned them and put them back on last time. Spotless.

Other than that, when I looked at/down the intake ports on the cylinders when I had the carbs off, I noticed oil, or what looked like oil. NOTICE: BOTH sides had a bit of oil in them...

so I sprayed it good with carb cleaner and turned her over with the kickstart with the carbs off and after a few cranks she looked clean down there.

So, after 5 hours of work, I prepped/cleaned everything and put it all back together and turned her over.

Well, she started, and sounded real good at first, then, after a minute, the right side began to misfire and smoke. This time it seemed the crank case was smoking, either that, or whatever is burning is burning all the way down the pipe...

Now, I've put in about 40-50 hours in on this project, and at this point (minus a headlight and front turn signals which should be here today) I should be pretty much done, just going over things to make sure she runs smooth and consistent (I wanted to use this bike to commute to work) before I spend the money to get the tags up to date and get insurance and all that jazz.

I have too many variables here for me to figure it out.

Things that are going wrong:

1. right side misfiring

2. smoking from pipe on right side

THINGS I THINK MAY BE THE CAUSE

1. Intermittent spark on right side. My guess is I need to do the lightbulb test on the plugs so I can see if right side isn't sparking.

2. i need that diaphragm/brass cylinder thing replaced in the carbs

3. the side has busted/worn rings and its leaking oil into the cylinder causing it not to fire. This scenario would leave me to sell it. I'm not dumping anymore money into this thing. If I can't get it to run good I'll just sell it and save my money, time, sweat, tears (not really), and cursewords (many of those) and save and buy a used, but in good/great condition bike.

OR the carbs just need to be tuned.

Since the lightbulb test would be real cheap, I'll try that first, but other than that, it is not that I am stumped, I just no longer have the time or patience for this. It was supposed to be fun, and while I got the bike looking nice, you can only polish a turd so much...

EDIT: I let it sit for about an hour and it seems it only starts right after I empty the carbs so that tells me it is flooding. But what do I know. If I was worth my salt as a mechanic I'd have it running by now. So it seems I'll either need to buy new carbs or buy a rebuild kit, but I'm not even sure the rebuild kits come with the diaphragm...[/EDIT]

EDIT 2: I'm ruling carb tuning out. I highly doubt that is the issue. I get spacy when i stay up all night. I really think I need to replace the diapragm, BUT, I ALSO THINK, the right cylinder rings ARE worn/broken. SO basically, what it boils down to, if i spend anymore money on this, I might as well set it on fire.

I was so excited about this bike. I guess it is time to admit to failure. I'm going to get drunk and fall asleep. [/EDIT]

What a waste of time and money and effort...

ANY help is appreciated, but if you reply, please expect a reply from me and have it go longer than 4 total replies.

I HAVE YET TO RIDE THIS BIKE

Images are here

imgur.com/a/2KyJL


Its a 750cc motor. This isn't that complicated at all, but I don't have a shop, in fact, I've only used tools out of a standard tool box thus far. I could strip the motor, hell, I'd really like to remove everything and paint the frame, and I would sure as hell love to tear it all down, clean it, and put it back together, i just don't have the tools, time, or money.

Salder69 wrote: Earlier this week, after all that hard work was done, I got the bike to start, and she sounded GREAT, both cylinders firing, firing sounded in sync. The only issue when I first started it, was it was smoking on the RIGHT SIDE exhaust.

That could be valve seals allowing oil to run down into the cyclinders. It will foul spark plugs.

Salder69 wrote:

Well, she started, and sounded real good at first, then, after a minute, the right side began to misfire and smoke.

I wonder if the coil is bad?

I would check compression and valve clearances first, do a leak down test if you have one.

You can get a new coil for this bike for $36 with wires from Z1. Might be worth it if the coil is old.

If that is so, I propose 2 questions to you in return.

1) I assume you mean ignition coils? The ones the actual plug wires come from?

and 2) if you could direct me to exactly where on z1 enterprises that would be fantastic. I have great difficulty navigating that site. Yes, it has the dropdowns and you can navigate the page, but are ALL the results it displays compatible?

A direct link would be fantastic.

I have insomnia and a touch of OCD and I have been up over 24 hours and my brain stops working correctly at this point.

I don't want to sleep, but I have to now, my body is shutting down and I can't think straight and I don't understand that site.

Also, apparently I can rule out a diaphragm (even though I would like to replace them eventually, if/when I get it starting on a regular basis) as this site says that the diaphragm does not affect idle speed. jbmindustries.com/Dimensions.html

The site above is slighty more confusing as Z1.

also, it may be the valve seals, as the oil was on the valve head itself when I checked with the carbs off.

Is this easy to fix? if not I'm selling the bike.

This was supposed to be relatively simple and most of all, enjoyable.

It has turned into a money eating nightmare.

The Z1 search engine never seems to work. Here is the four Ohm coil for the 750 twin bikes. Comes with wires, new plug caps always a good idea.

www.z1enterprises.com/ItemDetails.aspx?item=EM24-72451

Ignition Coil 4 Ohm Dual Output Suzuki
EM24-72451

Equivalent to OEM: 33410-45012 - Universal 4 Ohm Ignition Coil for Point Ignition - Mounting Points 90mm (3.5") Center-to-Center - Fits Kawasaki KZ900 Z1 KZ1000 1973-78 Fits some Suzuki models and early Honda CB750's Will fit with other applications with 90mm Mount spacing. Sold individually - two are needed for 4-cylinder bikes. Please check bolt spacing before ordering - some Suzuki coils are 4" bolt spacing... Got plug caps?


$36.00 Ea

Salder69 wrote: also, it may be the valve seals, as the oil was on the valve head itself when I checked with the carbs off.

Is this easy to fix? if not I'm selling the bike.

This was supposed to be relatively simple and most of all, enjoyable.

It has turned into a money eating nightmare.

Valve job is not that bad. It's normal maintenance for these engines. On mine, the valve seals failed about every 8 - 10 years regardless of mileage. If you plan to keep it, a valve job is a good idea. If you do a leakdown and find the rings are good, a valve job will probably freshen it up to run like new for quite a while.

Salder69 wrote: Also, apparently I can rule out a diaphragm

You have to carefully inspect them with a backlight. Mine had fine slits I didn't catch the first time.

Valve job is not that bad. It's normal maintenance for these engines. On mine, the valve seals failed about every 8 - 10 years regardless of mileage. If you plan to keep it, a valve job is a good idea. If you do a leakdown and find the rings are good, a valve job will probably freshen it up to run like new for quite a while.

I'm a bit stressed out about it right now, but yes, I plan to keep it. I looked for months for a fixer upper that I would want to keep indefinitely, so yes.

Thanks for the info.

next paycheck I plan to get the following.

Ignition coils, Starter Solenoid, diaphragms, a carb rebuild kit, a speedometer cable, and some pod filters.

I have heard bad things about the pod filters, but if I can get them for ~40 bucks, thats well worth it as the only hard part about taking the carbs off, is getting them into the makeshift airbox tubes, which I believe are parts of a radiator hose.

as far as checking the valves, anyway you can email me a link/photos of the manual/directions?

salder69@yahoo.com

Thanks for your help.

Godspeed