Smoke comming from ???

[Zin]

I've recently bought my second bike. ( never got to ride the first one... long story ) It's a 2005 Royal Star. I went through the carbs and still had an issue so I had a shop soak and put in new jets. Now it runs like a champ ( minor popping but possibly from old crud still running through system, or so I hope ). But since I've had it, it has smoked, originally I thought it was due to running rich or a carb issue, but now that I have gotten all of that sorted, it's still a concern. I'll put a picture up of where I'm seeing smoke coming from and try to explain it as best as I can.

 

I originally thought it was some oil/crud burning off of the pipe, but we are way past that time range and should have burn off by now 10 times over. So checking further it still seems to be coming from the same area, and I'm thinking it's the head cover gasket needing to be replaced or ??? But before I have someone or try to tackle it myself, I wanted to get input from the experts who have experience with similar rides. It seems to be smoking from the red circle area, but I have not been able to determine the exact point, and I do not see any oil or other spills in the area. This is happening on BOTH sides at the same area.

 

Any insight is appreciated.

 

[MiCarl]

Unless there is a strong sweet smell to the smoke it's probably oil.

 

I don't think the cylinder head gets hot enough in the area you circled for leaking oil to smoke. Odds are it's smoking near the pipes and you just don't see it until the smoke is rising clear of the engine. It may be leaking well away from where it smokes. Oil tends to migrate along the fins until it finds a place hot enough to cook off.

 

The cover gasket is a likely culprit, particularly given it's probably 14 years old. If you successfully find the leak I'd be willing to bet it's near the center line of the engine.

 

If the cover gasket is leaking it's likely not the whole story. The cover bolts don't tighten the cover, they tension little rubber donuts that push down on the cover. With age the donuts lose elasticity and don't put enough down pressure on the cover. Unfortunately given the quantity needed you'll spend more on those buggers than you do the gasket.

[Zin]

Unless there is a strong sweet smell to the smoke it's probably oil.

 

I don't think the cylinder head gets hot enough in the area you circled for leaking oil to smoke. Odds are it's smoking near the pipes and you just don't see it until the smoke is rising clear of the engine. It may be leaking well away from where it smokes. Oil tends to migrate along the fins until it finds a place hot enough to cook off.

 

The cover gasket is a likely culprit, particularly given it's probably 14 years old. If you successfully find the leak I'd be willing to bet it's near the center line of the engine.

 

If the cover gasket is leaking it's likely not the whole story. The cover bolts don't tighten the cover, they tension little rubber donuts that push down on the cover. With age the donuts lose elasticity and don't put enough down pressure on the cover. Unfortunately given the quantity needed you'll spend more on those buggers than you do the gasket.

 

So head cover gasket AND rubber bushings/donuts likely needing to be replaced. Gotcha. I'll try to take a video tomorrow afternoon to give a bit better of a view to double check. Thanks for the info.

[cecdoo]

I just dealt with the same issue after my 2007 sat all winter. I took a rag and put some denatured alcohol on it, went in that hole and wiped everything off as good as I could. Cleaned the fins, just wiped it all off. Doesnt smoke at all now. Will keep after it till winter when I will do the valves, and gaskets. You could probably spray degreaser in there and hose it down, I didnt want to splash water all over the place.

 

Good Luck, Craig

[cowpuc]

IMHO Zin,, your getting the best of the best advice thus far,, could not agree more with the above posts!!

 

I did notice you mention exhaust popping.. Most, if not almost all, of the popping exhaust issues I have had the honor of dealing with have somehow come back to air getting into the exhaust system.. Even a tiny little rust hole or a leaky gasket of the smallest version can cause popping.. I can't help but now wonder if your scoot has a header pipe to head donut gasket leaking a bit and maybe contributing to the smoke you are seeing somehow.. Long shot but what the heck,, what the hay...

[Patch]

IMHO Zin,, your getting the best of the best advice thus far,, could not agree more with the above posts!!

 

I did notice you mention exhaust popping.. Most, if not almost all, of the popping exhaust issues I have had the honor of dealing with have somehow come back to air getting into the exhaust system.. Even a tiny little rust hole or a leaky gasket of the smallest version can cause popping.. I can't help but now wonder if your scoot has a header pipe to head donut gasket leaking a bit and maybe contributing to the smoke you are seeing somehow.. Long shot but what the heck,, what the hay...

 

On this we disagree Puc. The air is simply the missing ingredient, the question must be why is there uncombusted fuel in the pipes..

Just encase you think I mellowed

[MiCarl]

On this we disagree Puc. The air is simply the missing ingredient, the question must be why is there uncombusted fuel in the pipes..

Just encase you think I mellowed

 

I've never tried to sort out the mechanics but air leaks into the exhaust are a well known cause of popping on deceleration.

[Patch]

I've never tried to sort out the mechanics but air leaks into the exhaust are a well known cause of popping on deceleration.

 

Yes but no that is actualy a low pressure cause weird one to explain. See the plate is closed so the thingy drops extra fuel.. we can get into it if y'all want

[cowpuc]

On this we disagree Puc. The air is simply the missing ingredient, the question must be why is there uncombusted fuel in the pipes..

Just encase you think I mellowed

ipt

 

Yes but no that is actualy a low pressure cause weird one to explain. See the plate is closed so the thingy drops extra fuel.. we can get into it if y'all want

 

IMHO,, this is what you may be missing.. As a natural/normal part of the internal combustion engine, in carbueetor equipped engines even more so the EFI if the injected engine is tuned properly as they can be tuned to more perfection, there is always an element of carbon build up.. While this is mostly noted for taking place in the combustion chamber (head, top of piston, deck and so on) due to the issues the carbon causes with performance (such as creating spark knock and misfiring), there is always a build up of carbon inside of the exhaust headers and exhaust system.. When heated by the exiting exhaust, carbon deposits will emit highly combustable fumes of their own that can and do create explosions (popping) if air is introduced into the exhaust system via and air leak in a cracked/pin holed pipe or thru a bad exhaust gasket.. I discovered this many many years ago while using a torch and a coat hanger to patch up an exhaust system.. I am sure you can replicate my experience simply by putting a plug in the end of your bikes exhaust and taking a torch and heating up the header pipe next to a known exposed small opening in the system ..

By the way,, for many years my lop eared gearheaded friends never believed me when I explained to them what I had experienced.. Their thought was always that there was no way that exhaust, passing thru the pipes, could possible get the carbon within the pipes to that kind of temp. This thought completely disappeared though when the first Titanium exhaust pipes came out and we were all riding dirt bikes one night with Ti pipes on them.. It was a beautiful site to see the looks on some nay sayer faces as the looked down at the brightly glowing red header pipes as the bikes were setting there idling..

[Patch]

There are many discussions within the points you make above Puc.

But remember assumptions are the mother of many a disappointments.

 

Sue carbon deposits glow around the edges, but the should only be a lite smooth layering of, so more that that we need to look deeper.

 

Sure we have a % of unburnt fuel in the pipes whether it be vapor or condensed.

Also there exists a potential for improper mixing of air/fuel reducing a more efficient combustion.

Yes that can be pushed thru into the pipe and yes air entering the pipe in sufficient quantity is the missing ingredient to allow for a second combustion; no argument there, and yes the closer to the exhaust port the greater the chance of said combustion.

 

But that is not my point. What I see often and I mean often is the answers is assumed to be un metered air not what is going on above it which creates the potential in the first place!

That is my point!

 

What is the existing conditions in regards to expected bench marks!

 

Lets remember some exhaust system have air injection for more than one purpose.

[Zin]

Sorry for the delayed reply, Work has kept me far too busy.

 

On the popping, it's not a major issue at this time but well worth a look once i start polishing the bike up. ( Only happens randomly when I twist and let off the throttle quickly)

 

Back to the original issue of the smoke, I'm going to follow all reasonable advice i can. I may not SEE any oil or gunk, but running some denatured alcohol and giving it a good clean wont hurt. If it solves, all the better. If not, I've got a quote for around 300ish for getting the rear head cover gasket replaced on it. I figured I'll have them do it when i have them put on new rubbers on front and back.

[cecdoo]

Been a few days, wondering if cleaning things up with alcohol helped with smoking? Curious minds:fingers-crossed-emo

 

Craig