I think they've switched between different designs of pump heads. The current one didn't appear to have that problem, and I cannot imagine why it would suddenly starting doing that any differently than a push-on pump. The outer threads don't unscrew from the tube, and it should be doing more than pushing in and out the middle part.

Joe blow sucked! Broke after a couple months.

Specialized Air Tool the best! Accurate gauge, pumps well. Dual sided head.

Lezyne? Gauge not accurate, pumps well, expensive, and the head is very sensitive. Only place it about 1/8 of an inch over the presta valve or it will get stuck. Also says so in the instructions but who reads the instructions nowadays?

Lol, you know, experiences and models vary. It's the the Specialized Air Tool (single head) that I've always had a problem with it grabbing the stem to tight and that leading to tube failure where the stem inserts into the tube. And yeah I've tried adjusting how tight it is, any looser and it won't grab the skinny valves well enough to fill the tire with air.

I agree with you on the Topeak Joe Bloe, I bought and returned one as it worked poorly as well.

Best Bike Pump = Lezyne Pump with a Hirame Pump Head. I have bought at least 6 different pumps and this combo is by far the best. Mine has lasted many years now.

https://www.amazon.com/KUWAHARA-HIRA...ustomerReviews

The Lezyne Steel Floor Drive was sent back for a refund. Gauge never worked consistently (for me), or, I never cracked the code in connecting.

Blackburn sent me a free Core Bike Floor Pump replacement for one that was leaking, and it works just fine. It even shows correct pressure right after I connect it to the valve / before I start pumping. Accurate too - checked with my Accu-Gage / Meiser gauge.

No experience with some of the models mentioned above, but can tell you this (pressure overdrive) works incredibly well for problem tubeless tires. You can pump it up to 200 psi then blast the air out.. I have found 180 psi is usually enough to seat a "loose" tire on the rim without having to remove the valve core.

Old thread, so I do expect the OP has made up their mind about what pump to get.

I agree with jrobe , Lezyne CNC with Hirame pump head is the best. The best, Jerry! THE BEST!

Throw away the stock CNC pump head, it's garbage. The Hirame is great. Maybe even the best!

It's the BEST.

I dunno about you, and I dunno what exact chuck it is because the none of the pictures I'm finding online seem to match it, but the chuck that came on my CNC Floor Drive maybe 3 years ago is a knurled thing that I just put over the valve and push to engage... and it is soooooo much better than every single flip lever chuck I ever used.

it's a dream. Especially as the flip levers tend to abuse tubeless valve stems, and the Lezyne takes almost zero force to engage and disengage, and none of that force is off axis creating torque on the valve stem.

I've been using a Lezyne for years. It's fine, well made, works every time. I don't really think about the chuck. I know how the chuck works, it works fine, I know how to hold the hose fitting while I screw it on. Three or four pumps, I'm back to target pressure. I don't really think about whether 85 lbs is accurate or whether it's not (smooth ride, no pinchflats, I'm good). Like, is this so friggin' hard? Screaming at the moon with pump hate? Hilarious. Maybe I need to be a millennial to appreciate the pump experience. Go ride.