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Discussion Starter #1
I have no idea what to look for. My track day got cut real short when I started to lose all power on my bike.

I got it back into the pit, and it was very hard to start. When it did start, It did not rev very easily at all. Even when the throttle was twisted.

After a few throttle twists, the revs did go up, and then oil started spraying out a tiny hole in the bottom of one of my exhausts.

Could this just be a bad plug, or am I looking at something serious?
 

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Sounds like you have a serious problem. If you actually have oil coming out of your exhaust, I would say you'd have a pretty major valve guide leak and you are losing compression. Are you getting a smoky blueish exhaust when it does run? First thing I would do regardless is a compression / leakdown test.
 

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Mexican Hard Shell Taco
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To me it sounds more like bad rings as it all started with the engine running, valve guides are more of a problem at startup. Anyway it looks like some big engine work is needed.
 

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From my experience, ring trouble tends to "go away or diminish" after startup because the oil in the cylinders helps seal the combustion chamber better. However, the rings are real bad, or even broken, absolutely. Get a compression and leakdown test done on them and let us know of the results. They will almost always point you to the direction of the problem. Good thinking susser.
 

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Here's my thoughts....


$$$$$$$$$$$$$$$$$$$$$$$$$
 

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Discussion Starter #6
I've checked and replaced the plugs. There was a black residue all over them. When I do get the bike to start, it sounds pretty for about 10 seconds, then the problems start. No idle, I've got black smoke comming out one pipe, and blue white smoke out of the other. Also, one exhaust output is warm, and the other seems to come out cool.

I'll go get a compression test kit today....Im going to try to do the work myself.

I just listed the bike for sale too......
 

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Check your oil for gas!!!! Do you have carbs? You could have a stuck float valve in the carb For that matter if it is FI you coulod have an injector stuck open
 

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If you have blueish and white smoke coming out of the exhaust, that sounds like you might have a blown head gasket. Your waterjackets and oil passages are leaking into your combustion chamber and is being burned. Let us know what the results of the compression test are. You should also take it to a shop and have a leakdown test performed too. That will point you in the direction of the problem.
 

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Discussion Starter #9
Ok, all ya'll giving input, thank your very much....


I ran the compression test...(this is pretty cool stuff)

SparkPlug Hole number 1 (Left side)
This one came out to about 125 at the end of each cranking session. Each cranking session was about 5 "cycles" of the engine turning over. The first "cycle" it only went to about 60, than the second woudl get close to 120, and then it stayed around 125.

SparkPlug Hole Number 2 (Right Side)
The first set of sessions went up to just over 160. Subsequent sessions hovered in the 130 range.

Im trying to locate my Clymer manual, Im sure it has the ideal compression pressure...but do these numbers mean anything to ya'll?

Im considering taking off the carbs just to look in them...probably a bad idea huh?
 

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Discussion Starter #10
Found The Compression Standard for my model:
Its 128 - 196 psi. So I think its low.

I think I've got a combinatin of problems.

The first thing is that my fuel mixture is to rich;indicated by the new left spark plug is already showing signs of blackness. I guess I have to adjust the carb to fix this. I hear its an artform to properly adjust a carb, I guess I'll find out.

The second problem with the gas spitting out of the exhaust, must be a gasket of some sort. I assume this is will be easy to identify with the engine taken apart?

I hope Im not getting over my head with this....
 

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When you performed the compression test, did you hold the throttle wide open? You want as much air as possible in that combustion chamber. Also, take off your gas tank and carburetors and pour a bit of motor oil into the combustion chamber. See if this makes any noticeable change in your compression test.

As far as adjusting carburetors, it is really not that hard. It is simple if you have an EGA machine. When doing blind tuning, it's good to start with the factory settings for your location. Call your dealership to find out these settings. From there, when you are tuning, if the motor RPM's go up, the motor is reacting positively to what you are doing. If not, go the other direction. Blind tuning will require lots of test rides, and a lot of patience.

As far as I am aware, there are no real gaskets in the Fuel system that will cause fuel to be coming out of your exhaust pipe. Fuel is fed by line from the tank, directly into the float bowls of the carburetor. From there, the fuel is atomized and sent into your combustion chamber. Fuel leaks could only be around the tank lines, or the caburetor itself. If you ACTUALLY have fuel coming out of your exhaust, you have a mis-firing cylinder, or an extremely rich running cylinder/motor. I would hardly think your bike would start or even run consistently if you had raw fuel coming out of your exhaust.

Again, compression tests are used only to identify a compression problem with your motor. A leakdown test is required to figure out where that problem lies and what component is causing it.
 

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The blue smoke is definitely oil, black/gray means rich, white means coolant...


The black plugs can be related to the oil burning. It also sounds to me like a blown headgasket.


Are you 100% sure there is gas coming out of the exhaust and not a mixture of gas/oil??? The gas/oil mix would be expected from a blown headgasket (the oil gets in, mixes with some gas, and that crap isn't burned, so it gets to the exhaust).

I really find hard to believe that there is coming gas out of the exhaust, the only time I have seen something like that was in a car with a stuck float, and the engine wouldn't start, as it was flooded but not hydrolocked.
 

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Discussion Starter #13
I ran the compression test again, this time with the throttle wide open. Left side was 187 and the right side was 190.

I also took the cylinder cover off. (that was a bitch, had to remove throttle and clutch cables). There was a rubber liner, and that looked to be in good condition. Is that rubber liner my "head gasket?"

I didn't get much further than checking the valve clearance with the cover off. I also tried to do a leak down test, but all the air just went out of the exhaust. I'll have to figure a way to plug that I guess.

Susser: yes, there was a gas/oil mixture spraying from one of the exhaust cans. I know for sure that there was gas, and I really think there was oil mixed in with it. At least it tasted like oil/gas. I thought it just might be gas mixed with the deposits in the can, but after a taste and rubbing it between my fingers, Im quite positive it was a gas/oil mixture.

It should be important to note, that I did wreck my bike several months ago. I've been in the process of repairing the fairings, so I just now started to run it again.

Does anyone have a link to how to adjust the carbs for a rich mixture. Im sure ya'll can tell, I don't know to much about engines in general. I think I shoudl first address the rich mixture. This will at least allow the bike to run better than it is now, and allow me to figure out where the second problem is coming from.
 

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Discussion Starter #14
Redstar11 said:
If you ACTUALLY have fuel coming out of your exhaust, you have a mis-firing cylinder, or an extremely rich running cylinder/motor. I would hardly think your bike would start or even run consistently if you had raw fuel coming out of your exhaust.
Ayeup, its fuel.
 

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The gasket on the cover over the valves is NOT the head gasket which is sounding like the problem. The head gasket, among other things, keeps the oil path and coolant path separated. Try to look at the oil and see if there is any coolant in it. Also look in the coolant for oil.

Did the engine overheat recently? That's one good way to blow a head gasket. You may actually have 2 problems. Head gasket plus something that's allowing oil into the combustion chamber (only one though?).
 

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Discussion Starter #16
The coolant reservoir is clear of oil. The engine has not overheated, or at least the temperature gauge never showed symptoms of it running hot.

Do I need to take the engine out to check the headgasket?
 

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first off, what bike is it?

I think your headgasket is fine. i don't see a need to get into the engine unless it is totally needed.

your compression is fine, so your headgasket is fine and no need to worry about that. since you said your bike was wrecked, that means it was laying on it's side, which is one way oil got in the chamber and now the engine is just burning up the oil that was in the chamber and that leaked into your exhaust pipe. is it smoking on the side that it was laid down on?

if you have gas coming out of a pipe, that is your problem. either your airfilter is put in wrong or got knocked out of place and is chokeing the gas, or a needle fell out of place in the carbs. I would check the air filter first, then the carbs. check your float levels and for any kinked fuel lines.

then check out your coils to make sure you are getting enough spark. make sure your plugs are gapped correctly also.
 

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oh, and you wont find oil getting in your coolant resevior, you will find coolant in your oil. I also suggest one of the things you do is an oil change and filter change because you can tell a lot about an engine by the oil(how dirty it is, if it smells like gas, etc)
 

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Discussion Starter #19
its an 2000 ex500, less than 4k miles.
its smoking out of both cans..ones black smoke, the other is bluewhite smoke. I can't remember which is which....but....and what you said does make sense.

I've just been fighting the problems so much, I didn't step back and take a look at the obvious.
 
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