Doctorot's '78 KZ1000 build

You have to do what you have to do! I'm glad you got to the truth of that circlip! Nice build!

Well its back together again. I'm starting to think it is indeed the clutch stack because when i removed a couple disks it easily shifted through the gears.

Went down to LA for the weekend to check out Born Free and brought the bike in my truck. I rode just over 120 miles down there. Other than the shifting issue the bike performed very well this weekend. Most of that was on the freeway and I was leery of cruising speeds on the fresh motor so I was driving like a total dipshit trying to modulate my RPM significantly. I have a dyno appointment Tuesday to get this thing super dialed in, and see what kind of numbers its putting out.

Well the dyna session didn't go as planned. The clutch starts slipping at 7500 so we weren't able to do a full pull but he did give me some jetting suggestions and advised to go to the OEM clutch.(got one on the way) He thought the shifting issue doesn't lie in the shifter Linkage or the clutch stack but thinks the shifter drum/arm is worn or assembled incorrectly. Further inspection required.

Got an aftermarket throttle on there. I had to modify the switch to get some room but I think it worked out OK. I will fill the letters in with 1 Shot eventually. The throttle throw is better; I can go WOT without re-positioning my hand but its still a pretty long travel so hopefully it wont be too twitchy. I also got the new OEM clutch in, changed the pilots and main jets, and fitted Oury grips. test ride tomorrow.

Cool.
Steve

Test ride went pretty good.

One size up on the pilot (20) fixed the stumble off idle, but it think i went one size too lean on the main (127.5), it pulled harder on the 130 i had in there before. The OEM clutch appears to have fixed the shifting issue. I can now still shift through all the gears easily, and I had it up to 8000 RPM in 4th and the clutch wasn't slipping. I think i might put some more gear in it; seems too tall right now, it won't redline before it runs out of power, but getting the jetting perfect will come before that. The cam caps are leaking again, as cool as they look i might switch back to the rubber OEM ones, these ones are super hard to seal anytime i change the valve gasket.

The aftermarket throttle i bought does not have a positive stop so when braking hard my hand will turn the throttle closed past idle and because its a push/pull throttle it will force the intakes closed past idle and the motor wants to die. Any suggestions on dealing with this? Its livable right now but I want to get the throttle as close to perfect as I can.

Don't the carbs have a stop screw?
Steve

Yes but apparently its not stout enough to keep the intakes from closing if you force the throttle closed past idle like under hard braking because it is push/pull. I think i may try to add a stop to the throttle sleeve clamp to resolve the issue.

UPDATE

The throttle action is really good now. I moved up to a bigger 36mm throttle tube for even quicker action, and I drilled and tapped a hole in the throttle clamp for a positive stop. works great.

I thought the shifting issue was resolved with the new clutch but it was just better. It still was difficult to down shift. I FINALLY figured out the root cause of the shifting issue. Way back when I was first tearing down the motor I got a used shifter off ebay to replace mine which had worn out splines. What I bought was was listed as a 1980 but actually got a 1981+ the main difference being the over-shift arm is 5mm shorter not allowing a full down shift. The easiest was to tell the difference between the shifters is the late model shifter has a small relief on the lower arm. The bike now shifts silky smooth with the undercut trans; speed shifting delight!

Finally got the cam plug caps to stop leaking, but when I removed the valve cover a screw fell out! One of the top idler assembly screws had backed out and the whole assembly was close to catastrophic failure. The leaking cam caps were a blessing in disguise because I probably would not have caught this until it was too late. I contacted Liska Racing about it and they sent me a new one free of charge. Hopefully that wont happen again.

Wouldn't the valve cover prevent the screw from coming all the way out? I'll have to keep an eye on mine.
Steve

Well I finally made it back to the dyna. I was close with the carb setup but the guy got it even more dialed in. Final settings are; 22.5 pilot, 132.5 main, needle clip second from bottom, mixture screws 3/4 turns out, and floats at 19mm. overall the throttle response is much crisper with the raised float heights and needle position. I only have 220 miles or so on it so he didn't want to take it over 8000 with the new cams in it. It got to 96.5 HP with another 3500k till redline. He thought it might make 100HP if he tested it higher so I'm calling that a win. I also had a chance to weigh it and its 480lbs with a 1/2 tank of fuel. Thats down 80 from stock!

the next debacle is the head-gasket is leaking oil....it never ends.