valve clearances way too tight

Hi guys.

thanks in advance for any help.

My carbs are out on a xj750, waiting for some replacements parts. So I thought while I'm waiting I mind as well check the valve clearances.

Every valve is extremely tight, can't even squeeze the smallest feeler gauge through.

Could this be because the bike has not run for a few years? Or it doesn't matter, and they should they all be changed now?

 

yes the shims need to be corrected, you may be able to swap some around

 

1. No, it's not because it was sitting for a few years. Valves recede into the head from RUNNING, not from not-running

2.I question how you did your measuring....... It's highly unlikely that every single one is out. What gauges did you use? What procedure did you use? How many miles on the bike?

 

+1 what they ^ said.

Gary H.

 

I did an XS1100 yesterday. It has 16K miles and it wouldn't surprise me if they've never been done before. The intakes are all still in spec, though on the tight side. All four exhaust valves were out. One shim size brought them all back in. I only had to use two shims that weren't in the head.

Do a compression test before you adjust the valves. If they're as tight as you say, the compression will be low. It's going to be tough to know what shim you need without a measurement.

See post #3.

 

I took the measurement with the cam lobes pointing directly away from the shims (i.e. pointy part of the cam lobe opposite to shim)
I used a .005 in feeler gauge, i think only one exhaust it fit under.

But I haven't had the bike run yet. I inherited it from my late father, I know he had the bike running, but hasn't in atleast 8-9 years.

The clearances being too tight means the valve is not even fully closing during power stroke right?

 

Not necessarily.

Too tight simply means too close to the cam to be in-spec. It means the valve opens too soon, and closes too late, causing lowered compression and lowered power. If the shim gets to where it rides on the cam all the time and there is literally zero clearance, then yes, the valve is not fully closing. But we need to know what your clearances are so that we can get the right shims in to get you back in spec.

Is that .005" or .005mm? Big difference.......measure in mm, please.

 

.005 inches / .127mm. My feeler gauge is imperial. That's the smallest one on the tool. I should probably buy a thinner gauge (if they sell them thinner?)

Bike has about 35,000 miles.

I understand why the gaps would get bigger, from the valve head slowly wearing out and receding into the cylinder head . How the heck would it get smaller?

thanks guys

 

The gaps won't get bigger. They get smaller. As the valve recedes into the head it is moving farther away from the piston, which mean's it it getting CLOSER to the cam.

Your feelers are too thick to begin with.
Your intake clearance in-spec range is: 11-.15mm
Your exhaust clearance in-spec range is: .16-.20mm

So your exhaust ones may be all tight, but you aren't thin enough to tell whether. Your intake ones are out of spec or not......

Now, that all said, if you're talking about a 750X, then that's a whole different ballgame.....

 

Be sure to buy true metric feeler gauges. You will be glad. I tried to use "English" feeler guages that were marked for "metric", and too frustrating. Bought a set of true metric feeler gauges, much easier and more precise.

IMHO the good old USA should just switch to metric and be done with it....

 

OP is in Toronto

 

I also recommend buying an extra, thin shim. I keep one in my valve shim kit. That way, if anything is that tight, you can just swap it out and take the measurement. I can get them for about USD $10 at a local dealer. Cheap investment to avoid long waits in the future.

 

OP is from Toronto, but we are just as imperial as you guys. I went to this auto/hardware store called Canadian Tire, and literally all they have are imperial measurements tools..

First i'll buy a proper feeler gauge and take it from there.

Do you guys know what the diameter is for the shims? So i can buy them after i measure before i take the out!

 

29mm.... but before you buy, check the shim pool.

Funny-- I can buy metric feelers as easily as SAE feelers in the middle of NY

 

Whats the shim pool? I hope there is a shim hot tub as well

 

GearWrench - Metric Feeler Gauge Part # 2274

KD tools part #2274 any auto parts store can order it for you using the KD tools part number

 

yup you just jump right into a tub full of shims...

there is a shim pool where you swap out your unneeded shims for shims you need.

post your clearances and shim size you have

 

Uxcell Metric feeler guage for $5.75 ...if you have Prime shipping it will be there in 2-3 days.

 

No. We. Are. Not. What's the speed limit on the highway. 100 miles? Nope. What does gas cost, $1.16 a gallon? I am surprised that your Crappy Tire didn't have metric, every tool set I have ever bought had both metric and imperial.
Sorry, I seriously dislike imperial. With all my 5'10", 200 lb body. Dammit.

 

So update, I bought some thinner gauges, still imperial. And I mean imperial as the nice round numbers are imperial, it has metric too, but not at nice intevals. (Not ideal, but I hate waiting for shipping online)

Most my intakes have clearence of 0.06 mm, most the exhausts about 0.08mm.
I wrote down everyone valve clearence though, everyone is way out of spec.

How would I do this pool thing? I can't take all the shims out at once can I? I heard you're supposed to do one at a time and replace. Not good to have the love press down on the bucket.

 

Depends on the size of the bucket and how desperate the love is....

 

right, chacal has blank shims for this very thing or if ship time bothers you, cut strips of 2 liter Pepsi bottles but watch they don't slip out

 

at any parts store
GearWrench - Metric Feeler Gauge Part # 2274
KD tools part #2274 any auto parts store can order it for you using the KD tools part number usaly 1 qay wait if not in stock.

first you need to remove shims 1 at aa time and record the size.it is on the back of the shim. then you will know the size you have and the size you need and if you can swap any of them.
then you post all the info and contact Hoggfiddles

this thread tells you how remove the shims. I use a 12 gauge solid insulated wire instead of zip ties.
Bigfitz's AIRHEAD VALVE ADJUSTMENT with Pics - parts I & II

you may only need 1 or 2 shims when all is said and done. your dealership may have some in stock if oem 28$ if aftermarket 8$ .
one is all you need to start moving them around or get a couple of plastic place holders or make some

 

Tell me exactly what each clearance is, and what each current shim size is.

 

What Hogfiddles will do is double-check what you need, send you the shims, then you mail back your old shims once the job is done.

 

Hey hogfiddles, sorry for late reply!

So if I tell you what I need, you'll send me shims, then i send you what I replaced? That's actually pretty sweet!

heres what i got...

(millimeters)

Intake 1 2 3 4

shim size 275 275 280 280
clearance .09 .05 .08 .08

Exhuast 1 2 3 4

shim size 270 275 270 275
clearance .15 .07 .10 .08


much much thanks

 

Ok, I did the math.....

You need:
4- 265's
1-260

I don't have any of those sizes right now , so you'll have to buy some--I'd recommend Len Chacal at xj4ever (resident parts guy....right here in the forums)

I'll draw out a chart for you if you need,, but here's what you need to do:

Ex1: install a 265, move the 270 to In1; In1 275 is removed

Ex2: install new 265,the 275 goes to In3;In3 280 is removed

Ex3: install new 260, 270 is removed

Ex4: install new 265, 275 goes to In4; In4 280 is removed

In2: new 265 is installed, 275 is removed.

Done, button it back up and go ride--find out how much power you have again. You will probably want to re-sync the carbs.

Dave

 

ok no worries. I found a yamaha dealer close to where I live, I can order from there.

thanks for the math.. you guys are the best on this forum!