1978 KZ1000-A2 "Barn find"

Kaylinator wrote: I can not for the life of me get the front brake to bleed properly. .... the brake handle still pulls all the way to the bars with no resistance. Help!

We really should have a sticky thread about this. It happens to everyone.

I don't have the diagrams handy, but here are the highlights.

1- the two holes between the reservoir and piston bore need to be clear. One is extremely small and often clogged. If either of these are clogged, there is no hope.

2- with your vacuum pump, try sucking fluid while the brake lever is tied against the grip. I think this should pull fluid into the chamber between the two rubber piston seals. My theory is that this volume does not fill when bleeding, and if there is air trapped there it's all bad.

3- Bleed it as best you can in any way you like, then tie the brake lever to the grip and walk away for 1-2 days. Come back and release the lever. There is a good chance it will have fixed itself. This works for many people (it happened to me).

Took the front brake system off the bike and brought it home thinking I might have better luck with it off the bike, with the added bonus of the old lady not being mad that I was at the shop.

I was wrong on both fronts.

Well I'll be damned. It was the relief port after all. I stared at it and stabbed at it with a welding tip cleaner the other day to no success. Just grabbed a sewing needle and it went right through. Works like a dream now.

Got the bike outside in the sun today for the first time since paint. Pain looks good. Can't wait to do decals, several coats of clear, and a cut/buff. Will look incredible with some shiny paint, a new seat, and an exhaust.


Also drove it up and down the road. Starts great. It's a private road in the country so was able to get it up to about 70kmh. Seemed to run pretty good. I think it requires a clutch adjustment though. Stalled a few times at crawling speed thinking the clutch was engaged when it apparently wasn't.

Also thinking I should do another oil change on it pretty soon. I changed it before I got it running, but not since.

Ordered my Delkevic exhaust tonight. I ordered it directly through Delkevic.vom (Z1E is out of stock). However looked after and realized I could have ordered it from the on eBay. Yes, it was more expensive on eBay, but shipping was way less. Could have saved myself nearly $100.

So today I cleaned out the pilot jet on cylinder 3 because it somehow became clogged. Or perhaps it was always clogged. No idea. Fired it up afterwards and it was running fine for a bit but then started bogging down, and died. If I let it sit for a bit it would fire right back up again. Couldn't figure it out until I noticed a bunch of oil on the ground. Thought a gasket went in me, but upon closer inspection, the air filter was covered in oil too.


It seems that the breather must have been filling with oil and killing itself.

I'm assuming that because I did not change the oil filter when I changed the oil that I must have overfilled it. Not entirely certain why it took until now to become an issue.

Anyway, ordered an oil filter and a new air filter today. Hoping that's my issue.

Mikaw wrote: Hopefully this isn’t coming to late but before you assemble the rear MC you need to run a 5/8 ball hone in the bore to break the glaze and give the seals a way to seat. I’ve had good luck with a 320 grit.

You don't need to 'break the glaze' on a master cylinder. the seals don't need to be 'cut-in' like piston rings.

There's lots of fuel in the crankcase. Drained it. I'm going to leave it work its way out overnight. Tomorrow after work I'll flush it out with some cheapo oil. Not sure why yet. Float height on #2 seemed high so I've corrected that. Hoping that was the cause.

cb900f wrote:

Mikaw wrote: Hopefully this isn’t coming to late but before you assemble the rear MC you need to run a 5/8 ball hone in the bore to break the glaze and give the seals a way to seat. I’ve had good luck with a 320 grit.

You don't need to 'break the glaze' on a master cylinder. the seals don't need to be 'cut-in' like piston rings.

We have already had this discussion,

kzrider.com/forum/5-chassis/613562-to-ho...the-question?start=0

Could be one of your float valves getting stuck open? Normally, the fuel would go out the overflow tube. Unless the overflow tube itself is clogged. From what you reported before about the clogged jets, you may be getting debris from your tank. If you don't have a couple of inline gravity fuel filters installed this may keep happening . The float needle could have also been effected by the debris. Of course, as you pointed out, it could have been your float level. But I would suspect a stuck needle. My bike was just out commission for a couple of weeks. All I did was change out the aftermarket single feed petcock to an original design dual feed petcock. And since I only had one fuel filter at the time I decided to leave it off, since I would be able protect both lines anyhow. Ended up with a couple of dead cylinders (clogged pilots) for my lack of due diligence. All sorted now. When I had filter protection I never had issues with the debris from the tank. I take the filter(s) off from time to time flush out the grit that builds up.

It seems to me that for this to happen, it would have required a bad float level/stuck needle AND a blocked drain tube. Checked today and all drains are clear, and all float needles are moving freely, so it has me pretty stumped. Really hoping my it was just the float level. I had been trying to adjust the pilot screws, so I suppose it's possible that at some point I had it so rich that it was taking on more fuel than it could burn...

If anyone has other ideas on what may have caused this, I'm all ears. Feeling a bit defeated right now. Was going to get the bike insured and registered today until this happened. The season is running out and making me wonder if I'll actually get it on the road this year. Almost makes me wonder if I should just get a jump on my frame up rebuild and shoot for spring.