Had to pull the head on the Triumph today. Unfortunately, the right side spark plug blew out and stripped the threads. I figured I would post a couple pictures of the internals. Unfortunately, I didn't think to get a picture of the bottom of the head before it was was off to the machinist.
73 Bonneville - 66k. Most of it's life with 20w50 Castrol, the last 4 years on Mobil 1 5w50.
Soaking the pistons with MMO in the meantime to try and get a little more carbon off. We don't have ethanol in our gas at all in my state so it's interesting to see the effects compared to some e10 bikes. Not very much carbon. A little more so on the left side which makes sense because before I went to the electronic ignition, that side always had a weaker spark.
This bike has had some gasket overhauls but is still the stock bottom end.
73 Bonneville - 66k. Most of it's life with 20w50 Castrol, the last 4 years on Mobil 1 5w50.
Soaking the pistons with MMO in the meantime to try and get a little more carbon off. We don't have ethanol in our gas at all in my state so it's interesting to see the effects compared to some e10 bikes. Not very much carbon. A little more so on the left side which makes sense because before I went to the electronic ignition, that side always had a weaker spark.
This bike has had some gasket overhauls but is still the stock bottom end.
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