XJ650 4K1 Oceania Valve Clearance advice

Hello All,

Was hoping to get some advice on valve clearance for an XJ650H Oceania Engine
Engine Shorty VIN - 4K1-001780
Engine Full VIN - JYA4K1008BA001780

Service Manual (XJ650G - which I believe has the same engine as the XJ650H)
specs
intake 0.11 - 0.15
exhaust 0.16 - 0.20

I measured clearance and got the values for all the installed shims and here are my results based on the shim replacement charts from the service manual, noting I used 2 decimal places for the measured value rather than the three decimal places indicated on my feeler gauge.

Code:

Yamaha XJ650H (4K1 Oceania) — Valve Clearance Check
Date: 30/05/2026 | Engine cold
Spec: Intake 0.11–0.15mm | Exhaust 0.16–0.20mm
New shim sizes per XJ650G service manual (same engine as 4K1 Oceania)

INTAKE
Cyl 1 | Measured: 0.20mm | Installed: 2.65 | Loose  | New shim: 2.70
Cyl 2 | Measured: 0.15mm | Installed: 2.65 | In spec | —
Cyl 3 | Measured: 0.13mm | Installed: 2.60 | In spec | —
Cyl 4 | Measured: 0.20mm | Installed: 2.60 | Loose  | New shim: 2.65

EXHAUST
Cyl 1 | Measured: 0.20mm | Installed: 2.60 | In spec | —
Cyl 2 | Measured: 0.20mm | Installed: 2.65 | In spec | —
Cyl 3 | Measured: 0.13mm | Installed: 2.65 | Tight  | New shim: 2.60
Cyl 4 | Measured: 0.15mm | Installed: 2.65 | Tight  | New shim: 2.60

Shims needed: 1x 2.70 (int cyl1) | 1x 2.65 (int cyl4) | 2x 2.60 (exh cyl3 & cyl4)

My question is, for cylinder 1, 2 and 4 on the intake side, and cylinder 1, 2 and 4 on the exhaust side.

Both before and after shim install they are all right on the edge of specs.

e.g. cyl1 intake after shim install should be 0.15 (on the edge of spec)
also cyl2 intake is right at the edge of spces, and if I look at it from my feeler gauge at .152 it is actually outside. Im just wondering if im being too pedantic.
Do I just stick to the service manual and do what it says from the charts?
Thank you!

 

Yes, "in-spec" means just that. In your case, just remember that clearances get "tighter" (the clearance gets reduced over time) so an intake clearance of 0.152mm....while technically "out-of-spec"....will soon be reduced to "in-spec".

Although clearances that are too "loose" (too big) will cause a decrease in performance/ power, they are not going to "harm" the engine, mechanically speaking. Valves that are too "tight", however, are a problem waiting to happen.......

 

Thanks Len! very much appreciated and understand your reasoning.
New shim order incoming, stand by