CV running rich

[Jack Klarich]

I am leaning toward valve seals, a compression test may be of some help also
You said you changed air cleaner? Are you getting oil in the filter?

 

[dolt]

Plugs look good, mileage is good, motor starts and runs good; not sure I would be concerned about collecting some soot in the exhaust. My saddle bags show some exhaust soot on the back of the bags after a 400 mile ride but a sniffer up the pipes show that the AFR is good; after all, they are "exhaust" pipes. You have to give the motor what it likes and if that means you have to clean up some soot on occasion, touch wood and hope you don't have a real problem any time soon. You might consider completing the Stage I upgrade by replacing the OEM air filter with a hi-flow filter which should lean AFR a bit.

That said, checking compression and leak down never hurts.

 

[HDDon]

Dolt my concern is the statement the OP made about the black smoke when he gets on the throttle.

 

[dolt]

Dolt my concern is the statement the OP made about the black smoke when he gets on the throttle.

Compression and leak down test would be my next steps. The OP has not changed jetting, bike starts and runs good, plugs don't show evidence of a rich mixture, mileage hasn't changed. Only change has been a hi-flow exhaust replacing the OEM exhaust which should not have a measureable impact on AFR but possibly leaning out the AFR a tad. Nothing the OP has posted so far supports the assumption that the smoke is the result of a rich mixture. Not saying a rich mixture is not the cause, just saying that the information posted so far doesn't add up to a rich mixture. Could be the enrichener but if that was the cause, mileage should drop off and the OP should be smelling fuel.

I don't know what is going on but based on what the OP has posted so far, I would be looking elsewhere.

 

[fin_676]

There is perhaps too much oil being thrown up by the breather which is being drawn into the engine during induction and on 91 evo breather is from the crank case that would perhaps indicate that there may be some blow by so a compression test and leak down may be the best indicators of an issue in the cylinders

Brian

 

[Jack Klarich]

There is perhaps too much oil being thrown up by the breather which is being drawn into the engine during induction and on 91 evo breather is from the crank case that would perhaps indicate that there may be some blow by so a compression test and leak down may be the best indicators of an issue in the cylinders

Brian

Assuming this is a plastic breather gear they have been known to crack and score the inner cam cavity, causing the returning cam chest to flood with oil, it has to go some where guess where? Leaking gaskets and too much oil in the top end

 

[fin_676]

Excess oil from a crankcase breather may not be evident in the air cleaner as the excess can run back down the pipe into the crank case as the pipe from case to air cleaner fits to the bottom of the air cleaner housing
but I need to dig out my original bits to be sure of that I have them somewhere

Brian

 

[ZZroadking]

Hi,
just a thought, are you using too much Seafoam? Perhaps a different measuring formula?
I understand just under 1oz per gallon.

 

[bus driver]

Sorry it took me to respond, but something got in the way of me playing with the bike. I had to work. I did pull the carb off just to recheck everything. Also I took the carb to Harley just to let them take a look at it. The said everything looked fine with it. Just for the heck of it I put new plugs and wires on it. I took a 60 mile ride today and it still developed black soot on the right pipe. When it cooled I checked the brand new plugs. They looked fine. I don't think the blow by is excessive because my air cleaner doesn't seem to get oil fouled. The Harley manual says I should have a 185 main jet and a 45 slow jet. My carb has a 175 main jet and a 45 slow jet. I honestly never noticed the soot until I changed the exhaust. That might just because the tail peice is shaped differently and now I can see it better. I don't think this matters, but when I was on a long road trip, the plastic/brass fuel inlet broke, and I had to do a roadside emergency repair. I drilled a hole in the plastic air cleaner backing plate a feed the extra fuel line I brought with me through the new hole and attached it to the. Brass bushing. I think a compression check might be in order.

 

[HDDon]

The only way to really check your plugs is to run the bike for 10 to 15 miles at full load (60 to 70 mph up hill is good) once you have the bike at full operating temp. pull the clutch and chop the throttle then coast to a stop and pull the plugs. Do not let the bike cool down first, this will give you a false reading.