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Discussion Starter #1
I was changing the air cleaner yesterday and there was a tsp or so of oil beneath it. I've been told the compression is low; is this oil just further indication that rings or valves are shot? At 44k miles? It runs strong w/no smoke whatsoever. What do ya think?
 

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Absolutely normal to have some oil pooled up in the bottom of the airbox.
 

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Since the bike runs fine, I wouldn't worry about a tsp. of oil in the air box, especially if it has taken quite a while to show up in there. I agree with Doughie, probably normal. By the way, what was the compression? If the cylinders are a little low, but close to the same, that may indicate some normal wear and you may be fine for another 44K and beyond. It's when there is a large difference between the cylinders that there may be a real problem.
 

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Discussion Starter #4
The dealer didn't tell me if the compression was balanced between the cylinders, and I wasn't smart enough to ask. He did tell me he believed it was heavily carboned and that a valve was probably staying open and that I probably needed an $1100+ or - top end job. (the bike was in there w/a starting problem--starter switch, he wrote it up as a performance problem, and the mechanic did a compresion check). When I picked it up he told me it was probably rings. I said, "at 44k miles?" He said that's not unusual w/a bike that's been driven a lot of short trips. The guys on this forum suggested several things I should try to get rid of the carbon (200 mile drives mostly at 70mph, Seafoam in the gas---I actually ended up using BK44G but will put a couple tanks of Seafoam through also). Can several tanks of gas w/that stuff in it damage anything in the carbs or anything else? Anything I need to know about running my own compression check, ie. when it's warmed up or cold? There is a pronounced ticking in the top end until it's warmed up--is that common--what might it be?
 

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jon lewis said:
The dealer didn't tell me if the compression was balanced between the cylinders, and I wasn't smart enough to ask. He did tell me he believed it was heavily carboned and that a valve was probably staying open and that I probably needed an $1100+ or - top end job. (the bike was in there w/a starting problem--starter switch, he wrote it up as a performance problem, and the mechanic did a compresion check). When I picked it up he told me it was probably rings. I said, "at 44k miles?" He said that's not unusual w/a bike that's been driven a lot of short trips. The guys on this forum suggested several things I should try to get rid of the carbon (200 mile drives mostly at 70mph, Seafoam in the gas---I actually ended up using BK44G but will put a couple tanks of Seafoam through also). Can several tanks of gas w/that stuff in it damage anything in the carbs or anything else? Anything I need to know about running my own compression check, ie. when it's warmed up or cold? There is a pronounced ticking in the top end until it's warmed up--is that common--what might it be?
First - the oil in the box is perfectly normal, especially if you run at high speeds frequently. MarkC can give you the low down but the design takes oil vapors and dumps them back into the air cleaner - a little over fill on an oil change can exaserbate the 'problem' which is why there is a drain tube on the air box.

If a compression check was done on your bike they should have logged the readings on the invoice.

I believe doing your own compression test is a good idea.
Remove one spark plug on both cylinders -attach the comression gauge, hold remove the spark wires from all four spark plugs and short them to ground, open the throttle wide open and spin the started for a couple seconds to get a good reading. Repeat and see if the reading is consisitent then change cylinders.

If you want to clean up the valve area you need to suck the seafoam or whatever product you chose, through the vacuum ports on the carb and let it spray directly over the valves and compression chamber. Let it sit for the recommended amount of time and then restart. Running it through the tank is fine for cleaning the carbs but the intakes valves need a direct splash of the stuff.

The ticking you are experiencing is pretty common in all 1100's. I wouldn't worry about it.
 

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Discussion Starter #6
If you want to clean up the valve area you need to suck the seafoam or whatever product you chose, through the vacuum ports on the carb and let it spray directly over the valves and compression chamber. Let it sit for the recommended amount of time and then restart. Running it through the tank is fine for cleaning the carbs but the intakes valves need a direct splash of the stuff.


Is it a fairly easy process to "suck seafoam" through the vacuum ports?
 
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jon lewis said:
When I picked it up he told me it was probably rings. I said, "at 44k miles?" He said that's not unusual w/a bike that's been driven a lot of short trips.
If you have worn rings, your bike will definately smoke (blueish smoke). I don't buy the carbon theory either. Just take it out on the interstate a couple times and rev it up. This will take care of any carbon buildup you might have. If the performance is acceptable, ride the wheels off it. Keep the oil changed and run a bit of SeaFoam through it.

Go for a second opinion or check the compression yourself before committing alot of money to a dealer.

Finding oil in the air filter housing is normal
 

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jon lewis said:
If you want to clean up the valve area you need to suck the seafoam or whatever product you chose, through the vacuum ports on the carb and let it spray directly over the valves and compression chamber. Let it sit for the recommended amount of time and then restart. Running it through the tank is fine for cleaning the carbs but the intakes valves need a direct splash of the stuff.


Is it a fairly easy process to "suck seafoam" through the vacuum ports?
Yes you just need port adapters - (5mm) you can order them through dennis kirk - or maybe pick them up from honda at higher price.

If you look at the Jetology sticky above, go to the third picture and find the numeral 4 - look up about two fins (about the 11o'clock) position from the numeral 4 and you will see a screw - that is an intake port screw.

Remove it (careful there is a little aluminum sealing washer that comes off too), put the port adapter in (one on each side) attach an 1/8" hose to each port (if you want to get elaborate you could put a 'T' in the line ), run the hose(s) in to the container of cleaner. You need to have them both suck cleaner at the same time.

Pinch the hoses shut start the bike rev it up a bit and unpinch the hoses and let the cleaner run into the ports until the bike stalls and you feel like several tablespoons have been delivered.

Let it sit (the cleaner should detail this procedure I know seafoam does) and then replace the port adapters with the original screws and start the bike, you may need to pull the plugs and wash them down with solvent, but it may start - just don't panic if it doesn't you haven't done anything beyond fouling the plugs to keep it from starting.

That is about the best you can do without taking it apart........and if it is running strong the plugs are not fouling with oil the gas mileage is good, and it's starting ok (now that the switch was fixed?), I would say you will be riding it when it has doubled it's current mileage.
 

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If you want to do a compression check yourself, go to Harbor Freight
and get a compression tester.
It's not the best one in the world, but hey, it's cheap and it works fine.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95187

The compression should be (by the book) 192 +/- 14 psi at 400 RPM.
I would say that if you can get 170 psi from the starter spinning it,
you don't have a problem.

Rings will absolutely cause oil blow by in the air filter.
However, there is ALWAYS some amount of blow-by that is present.
Due to the blow-by, this combustion pressure tries to force itself in to
the crankcase.
That pressure HAS to be relieved some how or it will blow the seals
right out of the engine and cause a tremendous amount of resistance
on the rotating assembly.
This pressure is vented to the air cleaner and it's known as PCV (Positive Crankcase Ventilation).
As the pressure is relieved, oil vapor travels with the air and condenses
in the air box... as others have said, this is perfectly normal.
If you go out to your car and find the PCV tubes on your car and remove
them, you'll see a slight oily residue in your intake tube where they connect. It's not a problem... it's a way of controlling emissions by
putting those oil vapors and fumes back in to the intake stream so
they can be burned... instead of releasing them to the atmosphere.
As DynoBobslick said, if the rings were worn that bad, you'd be puffing
some blue smoke AND you should also be noticing oil usage.

If you do the SeaFoam thing and let it suck it in while the engine is running, be VERY careful doing so.
Do it VERY slow. Liquid does not compress and if you suck too much
in you can bend a rod or hydro-lock the motor. You only want to put
a tiny bit in at a time.

If you go get a compression tester, like or similar to the one I posted
above, you can also do a leak test with that.
Instead of using the gauge, roll the motor around to TDC on one cylinder.
Screw in the compression tester hose to the plug hole and connect an air hose to it.
As air fills the cylinder, it's going to try to escape. A little air escaping noise is normal... you can't completely seal an engine.
But if you hear a lot of air rushing in to the crankcase, you have ring problems.
If you hear it trying to come back through the carburetor, you have an intake valve hung open.
If you hear it trying to come out the exhaust pipes, you have an exhaust valve problem.
If you hear it fill the cylinder and then the rushing of air comes to a real
light hissing sound, you don't have any problems with something not seating.
When doing a compression check or leak test, do as cbjr0256 suggests
and remove the coil or plug wires.
You don't want the engine trying to fire with the hose connected to the
plug hole. If it fires, it will blow the hose up.

One last thing, if you have a valve sticking, intake or exhaust,
you'd be having a tremendous power hit.
The bike would be VERY lazy...

If you haven't noticed any performance degradation and the bike
runs smooth, it's likely the dealer feeding you a line...
 

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Jon,
The vapors from the engine cases are routed to the stock airbox instead of to the outside world for pollution control. There might be an airbox drain hose with a plastic plug in the bottom that should be drained every service interval. If there is too much oil left in the airbox it might splash onto your paper air filter element, ruining it before its time.
A compression check would be good but a leakdown check tells you much more info. With the engine held at top dead center on the compression stroke, the cylinder is pressurized through the spark plug hole. The leakdown tester tells you what percentage of that air is leaking out (4% is very good). You can listen through the exhaust pipes, airbox and oil dipstick to see where it is leaking. You stealership should be able to do it for you. Do not try this at home. The tester limits the pressure so it won't ruin the gaskets.
 

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Rancor62 said:
The leakdown tester tells you what percentage of that air is leaking out (4% is very good). You can listen through the exhaust pipes, airbox and oil dipstick to see where it is leaking. You stealership should be able to do it for you. Do not try this at home. The tester limits the pressure so it won't ruin the gaskets.
Why should he not do it at home?

Very few people are going to have air compressors that go over 120psi,
maybe 150 max. Most people don't have 2 stage compressors at home.

120psi is less than the recommended specs for a compression test.

Doing it at home isn't going to ruin any gaskets.
 

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Discussion Starter #12
All thoughtful advice once again--I thank you all. Hope they hold a rally in Central Az one of these days so that I can meet ya. Unbelievable mountain roads and we've had 65 degree days lately.

Litnin's caution about the Seafoam procedure may scare me away from doing that--I've found that if something can be broken I probably will break it. A month or so ago a member-- I think it was Oliverman (or something like that) recommended misting water through the air box to "steam clean" the cylinder. Would that be safer and more effective in freeing up a possible Hanging valve? Is bad carbon the only thing that can hang up a valve? Jon
 

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jon lewis said:
All thoughtful advice once again--I thank you all. Hope they hold a rally in Central Az one of these days so that I can meet ya. Unbelievable mountain roads and we've had 65 degree days lately.

Litnin's caution about the Seafoam procedure may scare me away from doing that--I've found that if something can be broken I probably will break it. A month or so ago a member-- I think it was Oliverman (or something like that) recommended misting water through the air box to "steam clean" the cylinder. Would that be safer and more effective in freeing up a possible Hanging valve? Is bad carbon the only thing that can hang up a valve? Jon

As long as you do it very slow and don't put a lot in, you'll be fine
doing the SeaFoam thing.
Sometimes the way it's described, I think it can be read as
"stick a rubber hose down in the bottle of cleaner and let it suck it up".
That would be dangerous. If you get something like a 2 stroke oil mixing
syringe, while the bike is running, just dribble very slow the SeaFoam in,
you won't hurt anything. Just a drop or two at a time.
You'll run in to the same thing whether you use water, SeaFoam, mineral
spirits, etc..
It's liquid and you can't compress liquid. But if you do it in small quantities,
it will atomize in the air stream and will work fine.

No, carbon is not the only thing that can hang a valve open.
Buggered up valve guides, dry or warped seals, carbon, bent valves, can
all hang one up... Carbon is the most likely.

I doubt seriously you have a hung valve.
Like I said, if you had a valve hanging, your bike would be
really weak and low on power. It doesn't take a valve to be held open
much to cause a HUGE loss of power.
If an intake was hanging open, you'd likely some back firing also.

Does your bike use any oil between oil changes?
Does to puff blue smoke while it's running?
Does it have a lack of power?

If you answer "no" to all three of those questions, it's likely that nothing
is wrong with your bike and the dealer was just trying to get something out of you.
 

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I can't add anything of value more than what the expert above stated about how to test, but how long was it since you had changed your air filter? I think you have a normal case of oil blow back from what I have seen on my bike, which is at about the same mileage as yours.

Pros, would changing the air filter and checking it at some interval make the read easier? i.e. How much oil is normal in what timeframe?

I change my air filter every other oil change, and I ride about 80 miles a day at 80 MPH and it had some oil on it. No problems with the bike though.
 

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Discussion Starter #15
you know, mensa143, I changed the filter just yesterday. The mpg had dropped from 45 to 41 over the last couple of tanks and I thought it could be a dirty filter. It was blackish w/oil I think on the inside. We'll see what the change does for the mpg and I'll keep an eye on it. I have been changing it every 8k miles.
 
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