On Tue, 31 Dec 2019 16:19:30 -0800, Mark J. wrote:

On 12/31/2019 12:55 PM, AMuzi wrote:
or your burning wheels maybe

https://www.bicycling.com/repair/a29...rack-might-be-
damaging-your-carbon-wheels/


Although you might not expect your average human to be so dimwitted,
this has been going on for as long as I've been around bicycles. And
the surprised looks are just precious.

Huh! Does anyone know, is it supposed to be just the exhaust
temperature that causes this, or some chemical reaction to the exhaust?

An easy Yes and mre. There is whole host of chemical componds coming out
a car/MV's exhaust. The heat warms stuff open and "opens the pores' so to
speak.

(I wouldn't have thought exhaust could get a rim that hot unless the rim
was within a very few inches of the tailpipe - and I assume hitch racks
don't hold rims that close to the pipe - but then, I don't use hitch
racks).

Depends on the hitch, frame size and mounting methods, but can be an
easily overlooked future problem.