Lafuerza

Pulled riser and elbows. Risers and manifolds look like new inside except for end. Pix attached. Everything is sitting in Barnacle Buster 20% solution to clean up. Noticed soot on the inside. Any ideas on what causes soot buildup inside riser/manifold. Good gaskets were used too. Sigh of relief when I saw the condition of the manifolds and risers since I thought I would need new ones. Rusted up thermostat may have been the culprit bit will see what happens when I put it back together.

AllDodge

Soot is from running a bit rich. Pic doesn't show how bad just that its black. The plugs tell the real story, if its a couple or all of them

Lafuerza

I pulled plugs earlier to lube cylinders. Noticed they werent original spec but may be used. I ordered the correct ones amd will be installing. They didnt look too bad.

AllDodge

Not bad but are rich, and not having correct plugs can cause it among other things. There is a nice color chart in the link

https://motorizedbicyclebuilder.com/...ur-spark-plug/