1985 XJ700 X Looks like blowen head gasket

On some models Yamaha did stagger the jetting.

The K&N will lean the mixture out almost as much as running pods will. You might need to bump the pilots up too.

 

K-moe,

I have also worked on a few different bikes that had different jetting, but none of them were in line fours. Most of the jetting issues from heat were from the V twins. Not a pro here just the shade tree wrencher so I am sure there are some out there. I have to admit that seeing is believing though, so today I will do some searching and she what I can find.

So with the K&N filter you are thinking #40 pilots on top of the 105/107.50 mains? I will have to jump back into Len's area and do some more reading on that, I think most recommend bumping the main and pilots up two. Thanks

Wow should never started to read up on this topic...I see way too much info and that gets into the super science of it. Just want the bike to run well and not carbon up. I will play a little but not go too crazy. Understand the heat issue with the air cooled engines and the 2 stroke, but that has got to me for race environment. or at least more tuning then I am looking for. #40's are on order though, just to make up for the main jet change.

 

You're going to have to jet, check the plugs, and jet again if needed. The K&N shouldn't need as much of a bump as pods will, but the guidelines are just that; your bike, in your town, with your gas may need slightly different jetting.

 

K-moe, sounds good to me, once I get the rings seated again that will be the next step, unless she falls on her face.

Any word on using "colortune" I have read some different articles and there seems to be two sides to this. I know that is only for setting the Pilot jet setting but it seems to have good science behind it. It is great to see "dowski68" making some vids of the xj700 X, great to see.

 

So while I am waiting on parts, I thought I would measure the valves with the head off. My idea is to put the shims, buckets and cams back on with the head off the bike and then see if I can get the measurements. Is this a crazy idea or one that might work? Any feedback would be good.

 

I think that would work. You might want to measure them again after the final assembly just to make sure nothing changed.

 

You can use a colortune for setting more than the idle circuit, but you do need to be good at holding the throttle steady.

The only hary thing about measuring valve clearnaces with th head on a bench is making damned sure that the head is held securely and the valves have room to open without hitting anything. Best practice is to build a jig. You can cobble together a suitable one out of scrap lumber pretty easily.

 

....and making sure the carrier is torqued to the correct specs so that there's no false clearance

 

Cool thanks for the verification that it is a valid plan. Yes the wood jig is also the plan so that nothing gets damaged and scratching surface areas. Good weekend job...thanks again guys.

 

I made a mistake again....
You aren't going to build a jig. You will be building a fixture.

Long, long, long week.

 

Do not fret, we all have those . . . .
Anyhow after Tim builds his fixture he can do a jig (aka happy dance) as he will have over come another victory on his 'rebuild road'.

 

Jig "A jig is a type of custom-made tool used to control the location and/or motion of parts or other tools"

Fixture "a piece of equipment or furniture that is fixed in position in a building or vehicle.
"a light fixture"

The above pulled from the Wed.

LOL you guys crack me up...I get the idea either way, (clarity of writing/speech) A thing you make to hold a thing you have so you can work on that thing in the thing

 

I am quite anal about language. Ask my wife, she loves when I correct her!

 

So that did not go as planed, I will wait until I put her back together to check valve clearance. By the book after I get it running. Turning the cam and then trying to get a accurate reading was not happening.
I did have to do some grinding and polishing of the cam holder cover. The intake shim covers/sleeves on #3 when I first started this came out very hard. When I was putting in all the shims and the shim covers I was not able to put three of them in from the top. There was a definite rim around the top of all three intakes on #3 that was blocking the shim cover. I had to file down and then micro hone that ridge down. This had to be done as the shim sleeves have to be able to come out from the top when the cams come off to be able to change out the shims when needed. There was a little wear on the #3 intake cam journal too, cam looked good with no groves or wear.

 

My dad was a machinist. A fixture is used to hold a part for repair or machining. A jig is used for holding separate parts while welding them into a completed assembly.
Some shops may use those terms interchangeably; my father did not.

 

Seriously. I was going to say this.

Gary H.

 

Garry H,
Yes that job would take some serious "fixture" work to get the head to stay in place. About the first time it moved on me I didn't want to damage it, so that was that. I did take one intake measurement and it was so tight nothing would fit. Once everything is back together I will attempt it again, this time I am hoping at least a feeling gauge will fit, but I am thinking not. Not too sure what shims came with the factory setting, guessing they are all different by a bit. I don't have the specs off my bike at my pc but I can post them later.

This should be the week for lots of parts to come in the mail. Got the new jets on Saturday, gaskets and rings should be here soon.

 

Whichever shims were needed to get the clearnaces in spec. There are lots of parts in the head assembly, and each part has a production tolerance. No two assemblies will be identical, therefore there are no set thickenss of shims that a bike comes with.

Chacal sells very thin shims for just the problem you have (0.00 clearance). Get one so you can swap it around and find out what shims you need. Royal PITA on a X, but necessary. The alternative is guessing (guess two sizes thinner) and hoping you're right.

 

When you get the parts use the same approach as you did with the others...
Be meticulous, organized, take notes as necessary and ask as many questions as needed to correctly complete each task. Guessing should not be a option; knowing is.

Gary H.

 

Got the rings in the mail, tested for tolerance. .015 across the jugs, that is a good thing. Now just waiting on the gaskets to get here and she will go together. Getting the itch as the weather is getting nicer but still snow and ice on the ground. Spin off oil filter kit also came in so that will be going on soon. Sure will be nice to have that on the bike, ease of oil change is a must. Thanks again Len.