I'm looking at the stock air cleaner on my 2016 RG and it looks big, as in it blocks airflow to the rear cylinder.

I've read the reports about 150k + miles on bone stock Harleys, and I also understand these machines are overbuilt and they can take the heat.

I'm just thinking I can maybe increase the intake airflow just a little and drop the temp in the rear cylinder just a bit.

Is this a good idea or should I just leave it alone?

 

I’ve always went to a stage 1 air cleaner, pipes, and appropriate tune to make the flow better and reduce heat. I say go for it.

 

working in the bike is always a good idea

 

Why fix it if it ain't broke?

 

The BIG influence on cooling the rear jug is the FRONT jug. It blocks most of the airflow AND pre-heats the air going to rear jug. If you want a different air cleaner, go for it, but rationalizing improved cooling for the rear jug is pretty fanciful. Actually, so is a low restriction air filter. The airflow through the engine is pretty well balanced. Improving the flow in the air filter does nothing to improve the flow through the exhaust. Modify both and you will eventually reach the flow limit on the throttle body and VALVES. At sea level, atmospheric pressure is just under 15 psi. That is the maximum "push" you will get to force air through the various holes in the engine. When you reach the flow limit for that sized hole, any money you spend beyond that will do no good.

 

Mount it on the opposite crash bar from where you moved your oil cooler. Jus kiddin, but you are going over board with the heat issues IMO. I live in So Cal (Hemet) and soon it will be triple digit temps though September. I have had no issues with my 14 FLHTK or my 04 FLHRP in heat up to 115 degrees. As said before, "if it ain't broke, don't fix it."