Originally Posted by
noisebeam
Potential conflicting evidence to that model:
Of course it is possible check valve fails as it warms.
Or the seal increases resistance as it warms due to lack of lube.
I’ve had this kind of failure with a Lezyne Steel Drive. The pump started resisting pushing down and little to no air was going into the tire. I contacted Lezyne and was informed that the Steel Drive has a plastic check valve that isn’t meant for heavy or extended use…not that my using it at home was what I would call “heavy or extended use”. They suggested the Lezyne CNC pump which is rebuildable and has a more robust check valve. I suspect that part of the check valve is made of polyethylene which has a low melt point. Over a lot of tires, there is a lot of heat generated and the check valve may melt into place or deform.
Seals wouldn’t really cause an increase in resistance. Worn seals just let air blow by when pressure is applied…think old leather pumps