1990 TE510 valve clearances

Hi anyone know the correct valve clearance for my bike? Read somewhere the newer one's are about 5 and 7 thou or so I think, is this about right for mine? Think my exhaust one was 6 thou and the inlet was quite tight, about 2-3 thou. Been told if it's too tight it can burn oil, is that true as I've never heard it before? Went out on it today and it was smoking quite a bit so trying to figure out what's causing it.

Cheers

.004 Int .005 Exh.

Book calls for little looser but that opened up clearence errodes top of valve quicker.

Later George

OK thanks, I'm guessing having them set wrong wouldn't cause it to burn oil though? Are the valve seals likely to go with an older bike?

Valve seals could cause oil consumption yes, by allowing oil to bypass into the compression chamber & be burnt. Stretched valves & incorrect clearances cannot cause this. And yes, the older your motor is (age=hrs running) the more likely the seals will be to leak. Do a compression test & a leak down test if you're suspicious of them.

Of course even if either test shows evidence of wear, the issue could still lie with your piston & rings/bore wear or cracked head or head gasket.

To be sure, pop the head off, replace valve seals (not expensive), check piston & bore for scoring, check bore for uneven wear (oval shaping-see manufacturers specs),

check rings for wear/sticking, & inspect head for cracks.

Note that when removing used valves with intent to re-use, you should re-seat the valves & adjust clearances accordingly. You should use a dial guage to check bore wear but if you have good hands & eyes a good set of verniers can do.

Thanks for the info, I'm more of a 2t person so not really done much 4t engine work lol. Suppose if the rings are worn it'd be fairly obvious though, would it just be a case of checking for blow by on the piston? Head gasket seems ok, there's no evidence of water in the oil, think the valve seals sound most likely.

Thanks

Put ring in bore of cylinder look at end gap then take it outside, holding it up to sun lite look for light between cyl and ring. If so put new ring in bore and repeat if still see light cyl is worn or distorted.

If valve guide seals are suspect replace them. Take valves out clean and dry clean and dry out valve guides check clearences on valve stem to guide if getting loose will wear out seals. Worse is if guides are loose valve will bounce around on seat loosing valve sealing and the flexing of the valve can cause it to become 2 pieces, this gets ugly quick.

Later George

Cheers, will try that. Think the rings are ok tbh, took the head off yesterday and it looks like oil has been passing through the valve so I'll change the seals/guides when I get a chance. Took the rest of the engine apart as well though looks like the big ends on it's way out and the mains are completely worn out. This is gonna get expensive lol.

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