‘76 KZ900 LTD. Need some advice.

Pretty normal I suppose for 26k on the motor.

What’s odd to me here is that the #3 exhaust valve is black compared to the rest when it was the #4 cylinder spark plug that occasionally fouled out by sooting up. Strange days indeed.

Very possibly the carburetors as it was such long intervals over the years that I ran the bike. Will be going thru all 4 before I complete the project.

Valve lash is too tight. That about half of what you need. .15mm is about .006. If you lap them it will get even tighter. 

Was going off the manual that says .002 to .004 was in the proper range.

motomisfit wrote:

Was going off the manual that says .002 to .004 was in the proper range.

The clearance on the early Z1's was first specified at 0.05mm to 0.10mm but was quickly amended due to instances of valve burning, especially on the exhausts.
The amended figures are 0.10mm to 0.15mm and should be kept as close to the high end as possible when re-shimming.
If you have clearance of 0.11mm - 0.12mm it's best to go with the next thinner shim and a clearance of 0.16mm to 0.17mm etc .

Also the fouling on number 3 is likely down to leaking valve stem seals unless there were piston ring or bore issues on that cylinder

There have been issue with aftermarket valve shims. There are claims also it was just a bad batch and it has been worked out. Problem is some of the bad might be still in inventory. Best to not gamble and ALWAYS use OEM. They are cheap insurance. If you talk to your local Kawasaki dealer, some still have draws full and mine was willing to swap one for one. Just ask, can hurt. A member here suggested that to me so I’m passing it along.  If not source them of evilbay. You need 29mm diameter shims. They come 2.00-3.20mm in .05mm increments. 
 

If you are in hurry to get shims talk to your local BMW dealer. Some BMW Bikes and some other brands use the same 29 mm OD and thickness shim size.

www.tills.de/product-320.html

New Shims OEM Quality direct from plant 29mm

BMW

•E169 (F 650, F 650 ST)   (09/1993 — 04/2003)
•R13 (F 650 GS, GS Dakar)   (02/1999 — 11/2003)
•K14 (F 650 CS)   (11/2000 — 09/2003)
•K589 (K100, RS, RT, LT)   (05/1982 — 10/1991)
•K569 (K 75, K 75 c, K 75 s, K 75 RT)   (12/1984 — 06/2005)

Aprillia:

Aprilia Moto 650
Aprilia Pegaso 650
Aprilia Pegaso 650 Garda

and some Japanese Bikes:

Honda:
CB750C Custom - 1980-1982
CB750F Super Sport - 1979-1982
CB750K - 1979-1982
CB750L LTD - 1979
CB750SC Nighthawk - 1982-1983
CB900C Custom - 1980-1982
CB900F Super Sport - 1981-1982
CB1000C Custom - 1983
CB1100F Super Sport - 1983
CBX1047cc - 1979-1982

Yamaha:

SRX250T/TC - 1987
XVZ12TK/TDK Venture & Venture Royal - 1983
XVZ12DL/DKC2/DN Venture Royal - 1984-1985
XVZ13DS/DT Venture Royal - 1986-1987
XVZ13DSC/DTC Venture Royal - 1986-1987
XVZ12T/TC/U/UC Venture - 1987-1988
XVZ13DU/DUC/DW/DWC Venture Royal - 1988-1989
XVZ13DA/DAC/DB/DBC Venture Royal - 1990-1991
XVZ13DD/DDC/DE/DEC Venture Royal - 1992-1993
VMX12N/NC/S/SC V-Max - 1985-1986
VMX12U/UC/W/WC/A/AC/B/BC/D/DC/E/EC V-Max - 1988-1993
FJ1100L/LC/N/NC - 1984-1985
FJ1200S/SC/T/TC - 1986-1987
FJ1200W/WC/A/AC/B/BC/D/DC - 1989-1992
FJ1200AD/ADC/AE/AEC (ABS) - 1992-1993
FJ 600
FZ 600
XJ 550
XJ 650
XJ 750
XS 400
XS 750
XS 850
XS 1100
YX 600

Kawasaki:

KL 600
KL 650
KLX 650
KZ 900
KZ 1000
KZ 1100
KZ 1300
ZN 1300

You guys are awesome! Thanks

Unfortunately there aren’t any bike dealers of any kind in my little town of Lake Havasu. Going to have a look at the valves today after I get a spring compressor.

One of the best tools I in my box. No way I’d have been able to get this screw out clean without it. Sure enough a broken guide.

I was surprised to see that these sleeves aren’t pressed in. I thought they were. So if I go to a 1015cc piston, it’s the sleeves that get bored, correct? Sorry, probably a stupid question but I’ve never built a street bike motor before.

Yes, the sleeves are bored.

motomisfit wrote:

I was surprised to see that these sleeves aren’t pressed in. I thought they were. So if I go to a 1015cc piston, it’s the sleeves that get bored, correct? Sorry, probably a stupid question but I’ve never built a street bike motor before.

 

The sleeves should be an interference fit. They should not come out unless heat is applied to block!!

You do your boring and honing with the sleeves installed in the block.

That broken guide (part # 12053-019) is common when camchain gets loose. Very common problem in these motors.