Valve adjustment - what are your experiences.

I have an '83 XJ550K Maxim, that I've owned since new. It has 24K miles on it. The valves, if I remember correctly, were adjusted last around 10-12K miles. The book says every 5-8k miles if I'm not mistaken.

I have done a lot of neglected maintenance this year, and the bike is running better than a long time. I've not however, opened up the valve cover and checked to see if it is in spec. I have a neighbor that agreed to help me do it in the spring if I purchase the supplies (gasket, grommets and shim kit). The closest Yamaha dealer is an hour away, and wanted $400-$500.

My question is what is everyone's experience on how far out of specs things really get after 12-15k miles without a valve adjustment for this, or similar bikes. It isn't that I don't plan to do it, I'm just curious how often people find that everything really is ok. (My m/c mechanic neighbor drove it and suspects it can't be too far out of spec as it is running and starting well).

Also, can anyone recommend an economical shim kit? I don't want to wait until it is open, then order the proper ones, etc. Once I get the valve cover off, I want to be ready with whatever shims I will need. Maybe a dumb question, but are their likely shims to have on hand, if I don't buy a full kit?

Have a good winter. My bike was put away to hibernate yesterday. Winter storm today.

 

1. Yes, you need to inspect the valves, and at 24k some will likely need to be adjusted.

2. Don't buy a shim kit. You will very likely only need a few, and can move some of the others around to bring everything back into clearance. Check clearances, pull the shims one at a time to note what' there (make a table in a logbook so you have it for reference the next tme), and the only buy the shims you absolutely need. Member Hogfiddles runs a shim pool so you can trade shims with him as well.

3. Inspect the gasket and valve bolt rubbers. If they are hard (if your valve cover leaks they are likely hard; if they are original they are likely hard) then order new ones from user Chacal. The gaskets on the YICS engines (yours is one) can be reused several times, and the bolt rubbers can be used until they no longer press the valve cover down on the gasket firmly. Do not over tighten the valve cover bolts. They are of a shouldered design and do not provide the clamping force to seal the valve cover; the rubbers do that job.

Rubbers.

 

Then replace the shim. Do not turn the engine without having a shim installed at every bucket.

Use a ratchet wrench to bring them snug then use a allen wrench to do the final torque.

Gary H.

 

It's cool worry about it in the spring but not too much. Que sera sera
I am just back from the pub howeber

 

Yup, do check them

 

hardest part was getting the shim out of the bucket. used small screw driver then a junk feller gauge.

get a metric set K-D tools 2274 Metric Feeler Gauge

any auto parts store can order it for you

no way of knowing what shims you will need untill you pull them out and measure them or read the size on the back side.

29mm shims chacal sells them and Hogfiddles has a shim pool

and instructions on how to do it
AIRHEAD VALVE ADJUSTMENT with Pics

 

Our point is...you can't know this until you pull the existing shims and it's not cost effective to order a kit of shims and only use a couple of them.

Gary H.

 

chacal sells them his are supposed to work better than others
or google moto tool 90890-01245-00 bikebandits has then about 15$

 

Shim tool is optional. Search BigFitz's thread about the zip tie method. Many swear by it!

 

or single strand 12 gauge house wire.

bigger the zip tie the better sometimes you have to fold it to double it up
sometimes it is easier to do if the exhaust is off for the exhaust valves. access to valves is easier.

 

Pictures in this link using the solid wire:

http://www.xjbikes.com/forums/threa...tment-part-2-the-tool-vs-ziptie-w-pics.29209/

The valves basically pound into the seats on the head over time which reduces clearance

Another debate that might be worth noting - does valve clearance get tighter or looser as the engine heats. I used to be in the camp of they got tighter, as the expansion of the cams, shims, rockers, etc on the top end would reduce clearance. I was corrected by what I now believe, that valve clearance gets bigger on a hot engine, as the majority of the heat in the combustion chamber causes the valve and head to expand more than the top end, which results in a larger measured gap when hot.

 

The entirely depends on what clearance you are measuring (stem to valve-opening device, or valve face to valve seat), and what mechanisim is being used to move the valves. With shim over bucket (like we have) the valve shim-to- cam clearances generally get tighter as the engine accumulates more hours. Rocker's tend to get looser as the tappet pounds on the valve stem top. Desmos tend to get looser as their tiny shims wear, but can also get tighter early on as the valves wear in. Ther are a host of other valve actuation devices, and they all have somewhat different wear characteristics.

 

The shim sits in the bucket. The bucket sits on top of a seat which hold the inner and outer valve springs in place. When the cam lobe compress the springs the tool hold the bucket down from the top. As such the zip tie holds the valve/compressed springs open from the bottom which keep the bucket down. In both examples the lobe is then rotated to allow for measuring clearance. See Rooster and k-moe's explanation for how they get tighter.

Gary H.

 

You can spend $15 to get " the tool", or spend $2 for a pack of zipties, or spend $0 for a scrap piece of copper wire.....

You can use the tool, and spend an hour trying to get it to work---- and then do it all over when you find out that the notch isn't lined up correctly........ The go to the next valve-----

While, in the meantime, I'll have all my valves check with the ziptie by the time you get you second one out.....

I have two of the tools and use neither of them.

There is NO reason at all to remove the exhaust.

 

zip tie goes through the plug ole, when you remove the plugs you can see the open valve, the zip tie slips between the valve head and the seat
stu

 

The zip tie like a said go through the spark plug hole I used to tips and it holds the valve wide open and also allows the bucket to be rotated as needed under the cam. If you use the tool the dual holds the bucket in place and you cannot rotate it you have to guess how to position the bucket so it rotates to the right place first.

 

the zip-tie has to be doubled (for more strength) and folded like an L to go in the spark plug hole AND get under the opened valve. I think it is well pictured in one of Bigfitz's tutorials.

 

The link that Rooster posted has pics of the 'non-tool' procedure being performed with an insulated heavy gauge wire instead of the zip tie.

 

Imo learn it the "long tooth" way. Learn to use the tool, zip tie method and thick wire technique then choose which YOU prefer. In addition you'll always know it can be done and trip out some of your friends at the same time when you do it without the tool.

Gary H.

 

There's tutorials out here, read up on it… You'll get it quick.

Heck, I figured it out without a tutorial… It's simple:

Push the valve down with the cam, stick the zip tie and a hold valve open. then rotate the cam out of the way. Do your valve shim and swap, rotate the cam back down, remove the zip tie....go onto the next one. And it really only takes about as much time as it took to read this......

Or maybe about as much time as it took to correct the typos.....

 

camera and camp, really? lol

 

Guess that's what I get for trying to reply when I was that tired.

Hopefully it's all corrected now---- lol

 

I had mine off when i did the adjustments was just easier access to the exhaust valves than through the spark plug holes of a 550

i got the tool and its just a paperweight to me now got it to work properly once.
get the wide zips

 

I've no idea when or if a PO did this before me but I found only one of the values to be in-spec. I think the worst one was out by about 20.

I found the process to be fair easy once I got the hang of it. I used the tool, had a new gasket and compound from chacal and found a local shop that has a shim bank.

Here's 2 things that I wish I'd been told before I started.

1) The cam buckets have a small notch on them that allows you to put a small flat-head screw driver in and lift up the shim --- the buckets sometimes rotate as you turn the engine so if you pay attention to how each bucket rotates it's possible to position the bucket in such a way so that the notch will be accessible when the tool is engaged.

2) Once you figure out what your measured clearance is and what existing shims are - there is a chart in the book that tells you what shim to change to. You don't need to do the math

 

Thanks everyone. However, I wasn't really asking about procedure to adjust, that is well documented. What I was wondering is what people's experience was in terms of:
- mileage between adjustments
and what did this result in experience of:
- how much the valves were really out of spec

Thanks!

 

Well then--

Out of spec is out of spec.. Doesn't matter how far. If its out, it's out.

In spec is in spec; out of spec is out of spec.

 

I guess many of us mis-understood the question. When you put the clearance in spec if it is at the farthest (wide side) of the spec scale it will take a while before they are too tight. Iirc most models get checked every 5k miles. The 5 valve per cylinder 700s even longer.

Gary H.

 

And just cuz it's time to check them doesn't mean they have to get changed.... Only the out of spec ones

 

At least every spring,,, or every 5k miles.
And ditto to setting it to the far side of the spec scale, but always in spec!


and I use 'the tool'.
It is cumbersome, but I have used it often enough that I know it's evil ways. I'm a scaredy cat and fear The Fitz's warning of breaking carbon loose , blah blah blah.

It takes a bit longer, but on a nice spring day why not spend a little extra time rubbing on the XJ?

 

My experience - my 82 XJ650 has 17K miles when I bought it. Several clearances were out of spec. Correcting the clearances as well as stripping and cleaning the carbs and performing a vacuum sync transformed the bike from crappy acceleration to a rocket. It required two weekends to learn how and to perform the tasks.

 

as far as in in/out of spec, (say 15/20) you find clearances at 14,14,14,16. so you need +1,+1,+1,none.
but
I'd change the , none to a +1 and let the clearances be 19,19,19,21 rather than 19,19,19,16. the lash on all four is closer and the 16 will soon be out of spec.
i think it's called mean deviation
if you have the "tool" in and accidentally turn the motor the wrong way?

 

Polock , are you suggesting to put one valve out of spec? Bad boy !

 

Watchya gonna do?

 

35k miles on bike all valves were tightexcept 1 intake which sita at the middle of the spec. now all valves except that one are on the top end of spec
i will expect to only have to change 1 shim next time a shim needs to be changed
bike ran well tight runs alot better properly adjusted. put 3k miles on it will check valve clearance when i stop riding and compare to my records.
gonna be 43 degrees tomorrow see if i can burn through another tank of gas.

 

yup the way to do it . if the valves had piston clearance when tight will have it when loose (100th of a mm)

 

If you turn it too far you are FUBAR.
It's one of those situations where you must be focused.

 

Pretty close to 77 000 km, all valves in spec but one on the tight side of the spectrum when I checked 2 years ago. Haven't ridden the bike a lot since for many reasons. It was the first time I checked valves in my life so I was a bit anxious, with no reason actually.

 

These were my measurements before my motor teardown:

Cylinder One

• In - .000mm
• Ex - .076mm

Cylinder Two

• In - .102mm
• Ex - .165mm

Cylinder Three

• In - .076mm
• Ex - .102mm

Cylinder Four:

• In - .063mm
• Ex - .127mm

50,000 miles and I highly doubt those shims have ever been replaced.

 

Clearance chking is similar to capacity rating on equipment. It's to prevent the clearance from getting to tight. You can probably chk them every 6k miles and as long as they're on the wide side of the spec scale as Dave stated you shouldn't have to replace them for a while.

Gary H.

 

you might as well replace them all using Polocks suggestion
look for bmw shims they go out with more digits 2.625 instead of 2.60 or 2.65 for your marginal one

 

I'm going to have to remeasure everything. I'm in the middle of a total rebuild from the head gasket up. I sand blasted the head, cleaned out all the ports, lapped the valves, installed new valves guide seals, etc.