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Black Pistons??

Here's a pic of a piston out of a 2010 flhr with only 5k miles. Swapped out for big bore last week. Seems to me that every engine i take apart has a decent amount of carbon/oil build up on them, High mileage or not.



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Pretty nasty for 5k miles bet the pipes are sooty too wonder what oil was in that motor, seems to me with better oils and leaner engines we should not be seeing this unless we are having alot of ring and oil leakage past the valve seals IMO of building a lot of heads and lower ends
 
Pretty nasty for 5k miles bet the pipes are sooty too wonder what oil was in that motor, seems to me with better oils and leaner engines we should not be seeing this unless we are having alot of ring and oil leakage past the valve seals IMO of building a lot of heads and lower ends

I just changed the oil in this bike yesterday, he is runing hd std. 20w50

What do you think about the amount of oil/assy. lube used at assembly. I know that all engines are run at the factory before crated and shipped. We get them with 1-2 miles on odometer and they smoke a bit at initial start up after PDI is performed. just a thought
 
I just changed the oil in this bike yesterday, he is runing hd std. 20w50

What do you think about the amount of oil/assy. lube used at assembly. I know that all engines are run at the factory before crated and shipped. We get them with 1-2 miles on odometer and they smoke a bit at initial start up after PDI is performed. just a thought

That could do it, tho I am leaning towards looser tolerances in the valve guides to let a bit more oil drip on the valves to help keep them cool JMO Ford has done this for years and it always leads to premature wear on the valves and seats, GM used roto caps on the exhaust valves, they would spin the valve each time it opened a very good deal, I have buckets of them and I think the next heads I play with I might try them just because:s
 
This is just a thought but could the gas we are all using cause this. everything I read say that E10 does not burn as clean as stright gas. We all can feel that the engines do not pull as strong. Just a thought.
 
Wow...normal??? Fuel injection, 14.7 to 1 lean fuel mixture and engine was/wasn't burning oil? Somethings wrong there. Maybe after 15 or 20 thousand miles.
wilks3
 
DynaBob, did you have the habit of filling your oil level to the "full" line? When I did, I always had oil in my air filter. Could it be engine oil was just being pulled in through the air cleaner as a "slow drip".

I now run 1/4" below the full mark (Hot) for that reason. It was a hard habit to break. That would also explain why BOTH pistons were the same way.(if they were)
 
DynaBob, did you have the habit of filling your oil level to the "full" line? When I did, I always had oil in my air filter. Could it be engine oil was just being pulled in through the air cleaner as a "slow drip".

I now run 1/4" below the full mark (Hot) for that reason. It was a hard habit to break. That would also explain why BOTH pistons were the same way.(if they were)

Makes sense Hoop. Also if anyone is running the S.E. high flow AC with the snorkle tubes (as i call them) that directs the air/oil mist directly into the throttle body/carb, will possibly have more oil directed back into the engine vs. the stock AC or some others.
I really dont think this is a "problem" as every engine ive taken apart has had buildup on the piston crowns
Remember back in early 05 when they switched to the 7mm valves and were having a huge problem with valve seals leaking. Some would leak so bad it would close the gap on ur spark plugs after 1000 miles. Still have a few of these come in today. Guess some folks would rather change plugs and keep the oil topped off vs. Having the seals replaced.
 
Carbon build up should not have been that heavy, but then did you an engine break in procedure to seat the rings? The other thing is, if not done and bike was only run in town and never highway driven that would be normal, especially if the oil level was too high to start. As Hoop said, check to see if oil remnants are in the air cleaner and heavy carbon deposits in the exhaust. Just my 2 cents...
 
Like I said earlier, the oil was from tha factory. I did not change it until the 1000 mile service (same time I had the 103 kit installed) and it is syn 3 now. When I checked the level it was at the full line but not over. I attached the pics now. Also, I did break in the bike for the first 500 miles. Never went over 65 or full throttled it for more than a second or two occasionally. I varied my speed and kept the rpm's low and mid-range. Then, I rode it like I stole it. Bike always ran fine. No sputtering, east staring and quick response.
 

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Much better lighting & focus...now seeing them both, I would say that is definitely normal, no concern needed, those deposits are normal...

If you had just come off the freeway and immediatly shut the engine off, both piston tops would have been cleaner still.
 
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