Need help fast valve shim

My 82 xj650 was running rather poor so I decided to check the valve clearance after I did I found out that cylinder 3 if you start from the left is measuring at (0.50mm) for the exhaust and (0.25mm) for the intake can they be that far off with out somthing breaking the reason I ask is because all the other valves are off but only by a little

 

Valves having too much gap on them it's not as big of an issue as valves being too tight.
Exhaust which is the front of the motor should be .16 to.2 mm
Intake back of the motor should be . 11 to . 1 5 mm.
So your valves are not opening as far as they should be which would have kept the valves from being pushed into the top of the piston and bending.
It sounds like whoever adjusted them last mixed up the shims.

 

See the post in the do-it-yourself forms by big fitc 52 or the remake of that post by hog fiddles it explains how to do valve adjustments

 

If you wish, post all numbers here, and we’ll verify figures for you.

also, I run a shim pool too—

dfox

 

Thank you so much I was just wanting to make sure nothing broke I've adjusted valves before but never on a motorcycle and never with shims

 

I appreciate that I believe all the other cylinders are pretty much right but it goes as follows cylinder number 1 exhaust 0.18 mm intake 0.13 mm cylinder number 2 exhaust 0.18 mm intake 0.13 mm cylinder 3 exhaust 0.25 mm intake 0.50 mm cylinder 4 exhaust 0.18 mm intake 0.15 mm

 

So cyl3 is a mess. Pull those two shins out so we can find out what sizes they are. The size is stamped on the bottom side of the shim

 

I also have another problem in cylinder 3 the Piston hit the spark plug and it's making a tapping noise now don't know if it's related to the valves or not could the valves being that far off be making a noise

 

What spark plugs are you using that it would have hit the top of the piston? An XJ with correctly adjusted valves sounds like an old sewing machine. It should be tapping hi

 

to answer a previous question cylinder 3 intake shim is 280 cylinder 3 exhaust shim is 270 and they were the correct spark plugs my throttle got stuck at 10000 RPMs and I had piston slap just not sure if the noise is the valves all because of the Pistons now

 

10K isn't much over red line. I wouldn't expect valve contact at 10K. But at, say, 12K... Bent valves won't close correctly, and will have a lot of lash.

I'd bet you get low compression on #3 as well.

If you have a compressor, you can try setting the engine to #3 near TDC on compression and stick the air gun nozzle in the spark plug hole. If you hear a bunch of air blowing out the exhaust and/or out the carburetor, instead of pushing the piston down, then you can be sure you've got some bent valves.

 

I’d look close at a couple bent or stuck valves......there’s almost no way that a 270 and a 280 could have you THAT side open on clearances. If ANYTHING, you should be too narrow, and needing smaller ones.

 

Well I appreciate it I was hoping it wouldn't be that but it was stuck in the back of my head

 

yes it has zero pounds of compression on that cylinder do you know how the cam on those Motors time up or where the timing marks are I'm planning on taking the motor apart but wanted time before I do so

 

Setting the timing is with marks on the cams, and that’s all detailed in the factory manuals.

 

Do you know of a place where I can view the factory manual

 

You should buy one for yourself on eBay—-

otherwise, when you are ready to reassemble, we can show you the correct sections

 

On the timing rotor, under the left side end cover, there's a T mark to line up with the pointer for 1/4 TDC. Turn the crank CCW to align this. #1 cam lobes should be pointing out, IIRC, at #1 TDC for compression. I think there are some markers on the cam sprockets that you can check for alignment, too. You'll need to remove the cam chain tensioner at the back of the block before loosening the cam cap bolts.

 

www.xjcd.org has online manuals but you should get one

 

Well thank you all so much for the help I really appreciated it I pulled the head of the motor off and found the problem that made me want to cry what's the best place to buy a motor seeing this world I don't want to pull the Pistons

 

Is there damage to that piston, too? I guess I would expect there to be. Can you see it not aligning with the deck at TDC? Or is it just chewed up from bits of valve?

Shipping on an engine is going to be the killer. Finding one you can pick up near you would be better.

On the other hand, removing the jugs and pistons once you've got the head off is pretty easy on these bikes... so maybe just install a used head, pistons, and jugs.

 

With the amount of dings and dents all around that chamber, I bet the piston isn’t too great either, but can you show us the piston and cylinder first?

 

Is that cylinder 3. You're two hours from Atlanta Georgia XJ4ever may have a motor for you

 

I believe I could clean it all up and make it work but I want the power that I had I don't believe it's going to be there and ya I can go to Atlanta who do I need to talk to

 

you can email our supporting vendor from his web site www.xj4ever.com. that would be Len, or start a conversation with him here his name is chacal

I looked on creigs list and there is also a add for parts from a yard

you may also want to go to a 750 motor

 

I looked at it and they're not that much faster from what I was looking at am I wrong

 

So. How do the walls look

 

Its not unusual for the bore to be fine - in which case you need a head and piston - no biggie really. The question about the cylinder walls is relevant one.
Pistons are cheap, so are heads - if you buy a motor, can you be sure its good?

 

Since you have the head off already, it’s just a matter of sliding the cylinders section off, and then the piston is right there to replace.

 

The cylinder walls look really good for the bike having 40,000 miles on it and I believe I can clean up the cylinder head and just put new valves in a piston in it

 

Thank you so much I do believe that would be the best option so I can have the most power for my bike if possible

 

Make sure to have new gaskets on hand

 

Besides the full gasket kit pistons and valves what else do I need to put this Engine Back Together and have it near-perfect being that I haven't worked on a lot of these engines I don't know what useless your place and what you're supposed to keep

 

Well, that;s where you start, and as you put finish taking stuff apart, and then start re-assembling, don’t be afraid to post a pic and say “now what?”, Etc........ we’re right here and as long as you are willing to ask, listen, learn, do.........we have the answers and WILL guide you through, tiny step, by tiny step. You’ll get it done.

here’s the thing.......these bikes were “built by simple people using simple tools but with a GENIUS idea”. You can do it. We can help you.

dfox

 

I appreciate that so how do I pull the Pistons

 

There is a wrist pin that holds the piston on the rod. Don't forget to replace those nasty studs.

 

Should be a spring clip holding the wrist pin in place. Pop that out and slide the wrist pin out.

 

I don't see any Clips or retaining pins is there may be a place in the manual that will tell me how to take it apart that I can look at

 

I haven't removed pistons from this engine, but that's the way they are in other motorcycle engines I've worked on. Also, the factory manual, on page 36, says "Remove piston clips, piston pins, and pistons." and shows a photo of the spring clip being removed with needle nose pliers.

 

There are two circlips, one on each side of the wrist pin. Once you pull remove them, the wrist pin will slide out. I’d recommend replacing the bearing while your right there. When you install the new pin, make sure you use NEW circlips. DO NOT REUSE OLD ONES.

once the wrist pin is out, the piston will lift right off.

 

Okay well I can try to find that thank you yeah I've worked on a good many car engines never tackled motorcycle engines except for a Kawasaki CSR and I didn't go to in debt to it so I'm sort of treading on new water here really appreciate the help

 

That’s ok, you’re doing fine

 

Your circlips may just be like a C without the two extensions. You may need a needle pick or super fine screwdriver to hook one edge and start lifting it out. Wear eye protection because they WILL go flying somewhere. Last thing you want is for it to fly into your eye. Trust me, it’ll fly, you won’t see it or find it. You just want to make sure that you don’t see it because it flew too fast, rather then not seeing it because you just went blind.

dfox

 

that chart worked like a charm it was sort of hidden I didn't see him at first

 

Now the final question do you think it's worth spending the extra money to replace all the Pistons or just that one I've already decided to replace all the valves none of them look good

 

I think you should buy a good set of used jugs and pistons and install that. It will probably be cheaper and easier to find than one new piston, and the pistons, rings, and sleeves will all already be matched/set to each other.

 

Ashley the judge look pretty good there's hardly any snoring or where at least for the miles is on it but yeah I found used Pistons who was the about $150 a piece and that's crazy

 

Y’all got a strange sense of beauty....Ashley the Judge is ugly and she snores TERRIBLY. She’s got two blew eyes..... one blew this way and one blew that way. She needs a cpap machine. But to each his own. If you like her, keep her. Thinking about it, maybe it’s just the nice jugs.....

I bet mattiThundrr pops up now....

 

Stuff some clean rags around the connecting rods so nothing falls in to the engine. That would be hart breaking.