1982 xj650j valve clearance question

so im sort of confused, i see conflicting information on the clearance numbers.

i have the haynes manual, and it says they are the same (both intake and exhaust) and i also have a side cover (dont believe it was the original though) that has the clearances different for ins and outs.

can anybody give me a straight answer on if they are both .006-.008 or if they are .004-.006 and .006-.008?

i have looked around and i see people talking about a misprint, and i couldnt tell if they were suggesting that the misprint mostly concerned the euro 650 seca.

any and all info would be great as i have my numbers and clearances all checked just dont know what shims to order, or move around yet!

thanks

ps:

my numbers are as follows

#1e #2e #3e #4e
.1524 .0762 .127 .17779999
y270 y275 y270 y275

#1i #2i #3i #4i
.0762 .1016 .1524 .0762
y290 y290 y290 y290

 

Service manual for XJ650J gives different clearances for ins and outs.

Intake: 0.11 to 0.16 mm
Exhaust: 0.16 to 0.20 mm

The only place I saw the same numbers and consequently a single valve clearance chart was in the Euro style XJ650G.

According to your readings: exhaust 1, 2, 3 are too tight, so are intake 1, 2 and 4.

According to the chart, you would need three 265 shims for your tight exhaust valves and three 285 shims for your tight intakes valves.

#3 intake valvles is a bit loose but you shouldn't worry about that, it does no harm.

Others will tell if I'm wrong, I'm not used to the chart, I'm sort of practicing, lol!

 

ah, ok the numbers you give from the service manual you have (obviously you must not have the haynes workshop one i have ) are what i have on my side panel, which like i said, may or may not be the original one...tough to tell, but it seems like it might be correct.

so it sounds like i wont be able to do any swapping of my shims then? thats a bummer, but hopefully hogfiddles has the ones i need. thanks for the repy

 

Actually, I can't remember of any other bike that would have the same numbers on both sets of valves. My understanding is that exhaust valves need more clearance so they are in contact with the head for a longer time thus allowing them to transfer more heat to the head.

So same numbers don't make sense, unless these Euro exhaust valves are made of an alloy that is tougher on heat.

 

yeah, i mean idk i only have the haynes and it def has a chart for at least 1 model of bike (although it says my bike and the euro version) that has the clearances the same, but i agree, theoretically it doesnt make a ton of sense to me but im also quite novice when it comes to mechanics *shrug* so im relying on you all

 

Web....Look closely at the number I am typing here: These are directly off of the correct chart:

Intake valve clearances (engine cold) 0.11-0.15mm
Exhaust valve clearances (engine cold) 0.16-0.20mm

You need:

intake 1, 2, 4 - 285 for each. intake 3 is ok, though on the NARROW side of ok, not the loose side. That one will get tight sooner than the rest, so just make sure that you do check that one when it's time for the next check.

Exhaust 1, 2, 3 - 265 each. Exhaust 4 is fine and dandy.

I have the 285's for you, but I have NO 265's.......seems everyone needs them right now, I can't keep them in the box for more than a couple days. the last several I got went right out in the mail and never even got into the pool box. Let me see what I can do about getting a few of those in for you..........pm me.

Dave F

 

I typed the intake specs wrong, Dave did it right. The specs are between 0.11 and 0.15 mm.
So , Dave, why did you say the valve with the 0.1524 is on the narrow side of OK? My understanding is that 0.115 would be on the narrow side or tight side of OK, and 0.145 on the loose side of OK, but any intake valve clearance wider than 0.15 is not OK, it is just loose.

 

Because when I typed that I was jumping back and forth between your post, and my list.....and I looked at the WRONG thing just as I type that. You caught THAT one..... Yup, that's to the FAT/LOOSE side of the range.....it's fine.

Dave F

 

That makes one thing wrong for each of us, that's fair! lol!

 

Yeah......

Two wrongs, don't make a right.

BUT--------

Two Wrights made an airplane.................

Dave F

 

*cue rimshot*

 

Back to the original question:

The Haynes has it wrong. Your sidecover is correct.

Spec for all of the "airhead" XJs is .11~.15mm intake; and .16~.20mm exhaust.

 

The exhaust valve stems are in the exhaust gas flow. Intake valve stems get washed with cool air from the carburetors. Because of the temp difference the exhaust valves will grow more, needing more clearance when cold.

 

I noticed they are a bit different for XJ1100s:

intake: 0.11 to 0.15 mm
exhaust: 0.21 to 0.25 mm

Is this another misprint?

 

Can't answer for sure. I was referring to the aircooled 550/650/700/750/900s. The XJ1100 is a different animal, one that I forgot about.

 

thanks for the help guys


next thread im sure will be carb related lol