My friend has a 650 V-Strom. The front cylinder's exhaust pipe is a 1/4 inch at the bottom from the oil cooler.
We decided to wrap the pipe with fiberglass heat wrap. We used gloves to avoid the glass fibers. We put the black fiberglass in water first and then wrapped. What a mess. We used pipe clamps to keep the ends of the wrap from unraveling.
The next day he took the bike out and the gauge registered hotter. We cut the fiberglass off after that. We're not sure why the bike didn't run cooler.