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Those fancy plugs will go 100 to 150,000 in a Honda car with everything perfect.
They will glaze over in a heart beat on a bike or old carburetor car. They foul up a tad around town and then a high heat down the interstate and they have a insulated glass coating on them.
Interestingly, they don't even look bad. They get a miss on a car or won't start with a two cylinder.
That oil on the backing plate is pretty normal. It just runs down. Only atmosphere pressure pushes in or as most say drawn in the carb, so little oil is sucked in engine.
Last edited by Jackie Paper; Aug 24, 2025 at 12:31 PM.
ok alot of contributers said the same on the iridiums. Damn $14 a piece but you learn as you go. As for the breather it has some sort of tube and what looks like a 3" round air filter that hangs down from the OEM carb. Oil level was brought into question. I will definatley use your advice thanks!
Last edited by 97SpringerResto; Aug 27, 2025 at 01:04 PM.
I think your motor is completely done, cooked, burned up. Save yourself the heartache and by a new bike. I will take that one off your hands for free, no charge! Go ahead and sign over the title, I will be over shortly to pick it up and get that head ache out of your garage [/QUOTE]
All I ever got into my soft tail was 2.5 quarts of oil..
Sounds like somebody vented the breathers to atmosphere, which is good, but damn, that sounds like an awful big filter for that... I'm running 2 individual lines from each head breather down to the ground, no canister, no nothing.. If your umbrella valves are in any kind of decent shape and your return ports are not plugged, you shouldn't have any real issues and no need for such a big canister...
Last edited by 98hotrodfatboy; Aug 27, 2025 at 02:17 PM.
Hey group need some insight. i just put in new NGK BPR5EIX-11 iridium plutgs a week ago. Yesterday the bike wouldnt run. I pulled the plugs and the front was foul and the badk was caked. I have never seen plugs do that in a week. the ones i took out looked ok just no idea how old they were. Wire brush, some WD 40 and a gap tool i got it running just like new. i will pull them after cool down every time to see whats going on. There have been no carb adjustments. I did pull the filter and did a recharge on it. There was alot of what looked like oil on the backing plate. Open to the thoughts of the group.
Thx
JJ
Update. Reduced the oil in the system. Solved the front plug still fouling the back. Had to do a starter motor replacement and low and behold the rear cylinder intake had a leak. That problem solved now the result. Drastic loss of fuel mileage. Went from 34 MPG to 24. Suggestions for the next approach. Jets?
Absolutely...
Did this just start or was it like this since you became the new owner?
I picked it up in may what i noticed was it fouling the rear plug i ended up needing the starter replaced and my guy that put it in noticed an intake leak in the front which he repaired. i do see that it starts smoother, but since then im getting 23 -26 mpg where i was averaging 34. plenty of power at all RPMS and the rear plug is still fouling and the front is still fine.... Im baffled
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