#4 Plug fouling again, need advice

[Escobarclan]

'82 GS1000 Kat, pods, MTC open headers, Dyna coils.

Hey guys, I noticed #4 exhaust wasn't getting as hot as the others. I pulled the plug (OEM plug), re-gapped and grounded it, no spark.

I put on a new (OEM) one and got a fat blue spark. This is the second plug that's gotten fouled recently and in the same cyl. the others are burning nicely. This cylinder has decent compression but uses some oil, which is the source of the fouling.

How can I keep this from happening? Should I lean out the carb a little? How about a hotter plug?

Any advice helps.

https://www.escobarpolishing.com

[Escobarclan]

Thank you, the carbs are sync'ed.

I leaned the cyl 1/4 turn and she stiff hasn't fouled yet, gonna take her out again, she should have fouled by now. but as said above the rings in that cyl may not hve seated yet or are seating again now, knock on wood.

[Dave8338]

How long since the rebuild? I'de steer clear of the hotter plug just yet. What is the compression in that hole?

[Escobarclan]

was rebuilt several years ago. 3 cyls show 150-155, the #4 shows 115 so you can see where i'm coming from.

I'm at a store right now, still ridin', she's still not fouled fingers crossed.

[Dave8338]

gott-ch-ya... 115 isn't horrible but would explain the oil consumption and fouling. In that case, a hotter plug may be needed, time will tell.