Bogged down, now it won't start

I checked the oil level too make sure there wasn't fuel getting into in, and the level is right where I had it. When I took the carbs apart for a quick clean, the screen on the needle seat stayed in the hole. I was able to get it out with put damage, but I was a bit concerned that it stayed in the hole.

 

How many miles have you covered since doing the valves. They have to be checked ever 8000 miles according to my Haynes manual for my 900f.

 

You should do a fuel level test with the float bowls on the carburettors. This diagram is for illustration only as l am taking the photograph from the Haynes manual for my 900f.

 

Worth doing if you have not already.

https://www.xjbikes.com/forums/thre...312-tool-and-adapter-for-mikuni-carbs.129884/

https://www.xjbikes.com/forums/threads/can-someone-explain-the-wet-set-in-a-simpler-way.63243/

This test will show if extra fuel is getting into the carburettors because the float valve, or valves are not sealing properly. Old ones can leak.

 

You are doing all the right things. Have you checked all your electrical system, cleaned ground connections, cleaned coil to harness plugs etc, bit of WD40 sprayed into them. Fuel out means the mixture is not being ignited and fouling the plugs. Tighten the plug caps on the leads turning them clockwise. I would remove the plugs, dry them with a cloth and clean with a soft wire brush, connect it to another battery and try starting the engine.

Oh do you have the original fusebox? That causes a lot of electrical problems on our bikes, better with a blade type fuse box. If you have the original one change it asap.

 

Would love to figure this out.
I have the tank off the bike right now, so when I go to hand crank the engine I won't be adding any more fuel to the plug hole.

 

Yes will we persevere. It is to see if you get any fuel out. I hope you don't. Use a torch to see if the piston crowns are wet with fuel.

 

It will be something simple, it usually is. A bit of detective work

 

I haven't checked the electrical yet, and not sure where to start. Brand new coils. Changed the fuse box

 

Maybe 2000 km

 

No fuel there that I can see.

 

Try car battery to make sure if you can.

 

I don't have an extra car battery, and it's raining out, so I'm not going to take the one out of my car. Should I be testing the coils even though they are only a year old?

 

Check coils but l would be surprised if they were faulty. Once it's dry you can use jump leads if you have them no need to remove battery just get bike alongside car. Just if you want to.

 

That might not be until Tuesday the way it's raining here.

 

So I checked the spark plugs with multimeter, and the one that had the gas coming out was a lower reading than the other plugs. Could this have caused the issue?

 

Possibly do you have a spare plug to try?

 

Yes. Going to see what it does. It stopped raining here, but my son has my jumper cables. I'll try with the battery on the bike.

 

. Started the bike. Checked the plug hole. No gas coming out. Synced, and when I started the bike with the color tune on, flames shot out the exhaust and gas was dripping out of the plug hole again.

 

Your engine is flooding so it must be a carburettor issue. I have never seen flames coming out of an exhaust or fuel coming out of a spark plug hole. I have heard popping from an exhaust system but never this.

 

I'm going to check the valve shims. I just did them last year, but when it starts, it runs so rough. Ya it backfires like crazy now.

 

Post a video if you can when you are trying to start it. Slightest spark plug fouling will stop the engine running properly because the TCI produces a weaker spark than a CDI but the former has a longer duration spark I was told. But I am far from having in depth knowledge about electronic ignition systems.

 

Checking the valve clearance first.

 

Here's what I get.
Intake1 -.007
Intake 2 - .006
Intake 3 - .004
Intake 4 - .006
Exhaust 1 - .013
Exhaust 2 - .009
Exhaust 3 - I can't get the gauge in. Too tight.
Exhaust 4 - .009

Something is out of whack

 

Cold engine clearances.

Inlet 0.11mm to 0.15mm

Exhaust 0.16mm to 0.20mm

Yes l am surprised it runs at all.

 

It was a little warm. Maybe I should take the readings again tomorrow.

 

Yes it's got to be cold leave it overnight. Carburettor balancing is futile if valve clearances are out. You are settling the carburettors to the vacuum in the cylinders. That's what sync is. Too narrow clearances valves open early too wide clearances valves open late.

 

It seemed to be running fine until this last week. I'm always syncing just a little.

 

You should not need to sync often do it at the service intervals. My manual states 4000 miles for carburettor synchronization and 8000 miles for valve clearances. If they are synchronized after the valve clearances are done what is the point in doing it more often?

 

I might have taken the readings wrong. Going to follow Hogfiddles "how to"

Rotate the crank (forward, CCW) so that each cam lobe in turn is pointed "skyward" away from its bucket at a 90 degree angle from the surface of the shim, and check the clearance between the heel of the cam lobe and the top of the shim.

I thought you have the lobs pointing away from each other, or at least that's how I measured them.

Note to self, Youtube isn't always right. LOL

 

Yes follow the guide.

 

I followed the instructions and measured with the lobs away from the bucket, and here are my results.
Intake 1 - .004 Shim inside - 265 Replacement - 255
Intake 2 - .006 Shim inside - 275 Replacement - 270
Intake 3 - .005 Shim inside - 275 Replacement - 265
Intake 4 - .005 Shim inside - 280 Replacement - 270
Exhaust 1 - .010 Shim inside - 255 Replacement - 245
Exhaust 2 - .007 Shim inside - 265 Replacement - 255
Exhaust 3 - .0015 Shim inside - 260 Replacement - 245
Exhaust 4 - .005 Shim inside - 260 Replacement - 245

Not sure how things got so out of alignment.

 

So have you changed your shims? If so is it running better?

 

Parts on order

 

Those sure look like readings taken with SAE feeler gauges, if so only exhaust 1,3, and 4 are out - all four intakes are good to go

Intake spec .004 - .006 in (.11 - .15 mm)
Exhaust spec .006 - .008 in (.16 - .20 mm)

Per the FSM you can use either metric or SAE gauges, most prefer metric, but I prefer SAE because you don't have to stack individual gauges.

 

OMG, did I order the wrong parts now! FFS!

 

Thinking I should go and put the original shims back in and measure again. I might have screwed this up from the start. I'm definitely not a mechanic. Lol

 

Are all your shims removed??

 

No. I kept a recording of all shims I originally had and the ones I had replaced. I'll put the originals back in, take readings and figure out where I'm at then.

 

So if the numbers were SAE you look good on the Intake side, I would just worry about the Exhaust:

Ex 1 has 255, needs 260
Ex 3 has 260, needs 245
Ex 4 has 260, needs 255

Just swap Ex 1 and 4, and find a 245 for Ex 3 -

 

Wouldn't I need to take readings from when the original shims were in? If I made the same mistake when I did the original shim replacement, the readings would be off, or am I missing something?

 

If these readings are accurate and SAE then no you don't need to start over, you just need to correct the one's that are truly out of spec - Ex 1, 3, and 5. You can always measure again while you are there, but just be sure to calculate any shim changes based on whether the measurements are SAE or metric

 

Finally got a chance to work on the bike. Had it running. Synced, color tuned, synced again. Still back fires, now it happens when I shift into first.

 

Checked the clearance again, and I switched 2 exhaust shims and 2 intake shims. Switched them, turned the crank about 4 times and measured them again. Now all are correct. I'll start it up tomorrow.

 

Have the bike running. Still not quite right, but it's running. More fine tuning over the weekend. Many thanks Franz, Rooster53 for the help. Still wondering why the shims went out of whack, because the bike was running fine last year.

 

You should be able to get the carburettors synchronized properly now with the valve clearances right.

 

Went to start it this morning and with 3/4 choke, it was idling at 700. Wouldn't get any power. Shut it off and took my car. Try again tomorrow.

 

Had the bike running today. Put new spark plugs in. Checked the spark plugs after running for a bit, and 1 was a little wet, 2 was white, 3&4 looked good. Went to use my colortune and it slipped out of my hand and the glass broke. Going to have to set the air fuel mixture bit by bit for now.

 

I was looking through some old posts and I might have the main jet and air jet backwards.