Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Pump feels like it engages only near end up stroke - whats up? (Lezyne alloy floor)

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Pump feels like it engages only near end up stroke - whats up? (Lezyne alloy floor)

Old 05-15-15, 10:02 PM
  #1  
mattkime
Senior Member
Thread Starter
 
Join Date: Jul 2006
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Pump feels like it engages only near end up stroke - whats up? (Lezyne alloy floor)

I have a lezyne alloy floor pump that i've had for about two years. when i go to pump, there's very little resistance at the top of the stroke (no air going in?) and then resistance increases near the bottom (finally engaging?)

what the heck could cause this? is there any maintenance that could be performed to fix the pump?

thanks,
matt
mattkime is offline  
Old 05-15-15, 10:03 PM
  #2  
corrado33
Senior Member
 
Join Date: Jun 2013
Location: Bozeman
Posts: 4,135

Bikes: 199? Landshark Roadshark, 198? Mondonico Diamond, 1987 Panasonic DX-5000, 1987 Bianchi Limited, Univega... Chrome..., 1989 Schwinn Woodlands, Motobecane USA Record, Raleigh Tokul 2

Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 1125 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Depending on the pump, it'll take a few inches for the seal to flip around and "engage" in the correct direction. That's my guess.
corrado33 is offline  
Old 05-15-15, 10:18 PM
  #3  
Ball Bearing
Senior Member
 
Join Date: Dec 2013
Location: South Coast of Western Australia
Posts: 254
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 150 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
My Lezyne alloy floor drive acts oddly, too. I took the thing apart and re-greased the plunger and made sure that the valve at the bottom was not fouled of blocked. After putting it back together I put a little silicon grease on the chuck O -ring. After all that it still is a bit dodgy. Next, I'll try a new chuck. I'm really disappointed because the pump has been used only weekly for a year and a bit.
Ball Bearing is offline  
Old 05-16-15, 01:44 PM
  #4  
Wheever 
Senior Member
 
Join Date: Jun 2014
Location: Stamford, CT; Pownal, VT
Posts: 1,145

Bikes: 2015 Trek Domane 6 disk, 2016 Scott Big Jon Fat Bike

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 147 Post(s)
Liked 3 Times in 3 Posts
Same thing happens to mine. I took it apart and swapped around the bumper O-rings for the seal O-rings and that fixed it. Then went out on bought some O-rings of the right size just to have around for when it happens again. (I think one of the O-rings had developed a flat spot.)
Wheever is offline  
Old 05-16-15, 02:23 PM
  #5  
Jed19
Senior Member
 
Jed19's Avatar
 
Join Date: Oct 2004
Posts: 4,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Wheever View Post
Same thing happens to mine. I took it apart and swapped around the bumper O-rings for the seal O-rings and that fixed it. Then went out on bought some O-rings of the right size just to have around for when it happens again. (I think one of the O-rings had developed a flat spot.)
Ding, ding, ding, we have a winner. Yes, the o-ring is probably done. You need to take the pump apart, take off the o-ring, replace it with the spare o-ring that always come with the pump, then all is gonna be well again.

And I also use silicone grease on my rubber o-rings too.
Jed19 is offline  
Old 05-16-15, 06:01 PM
  #6  
Wheever 
Senior Member
 
Join Date: Jun 2014
Location: Stamford, CT; Pownal, VT
Posts: 1,145

Bikes: 2015 Trek Domane 6 disk, 2016 Scott Big Jon Fat Bike

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 147 Post(s)
Liked 3 Times in 3 Posts
Not to pick nits, but that's not a "spare" O-ring, it's a bumper to keep the metal bits from slamming together. But yes, take the bumpers and swap them into the seals and you're good to go!
Wheever is offline  
Old 05-16-15, 06:25 PM
  #7  
digibud
Senior Member
 
digibud's Avatar
 
Join Date: Oct 2009
Location: Further North than U
Posts: 1,993

Bikes: Spec Roubaix, three Fisher Montare, two Pugs

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 37 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Lezyne will send you new O rings if you ask. At least they did for me. It seems a common problem with their pumps which are otherwise quite good. I have recommended the pump to two friends who both had issues.
digibud is offline  
Old 05-16-15, 08:16 PM
  #8  
rmfnla
Senior Member
 
rmfnla's Avatar
 
Join Date: May 2005
Location: La La Land (We love it!)
Posts: 6,330

Bikes: Gilmour road, Curtlo road; both steel (of course)

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 268 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Stupid me; I bought an Aieron pump from Performance for $13 about ten years ago and have never had a problem with it.

Of course, it's not a fancy alloy pump so I must be missing out somewhere...
__________________
Today, I believe my jurisdiction ends here...
rmfnla is offline  
Old 04-04-18, 07:00 PM
  #9  
cbike
Senior Member
 
Join Date: Apr 2008
Location: Iowa, USA
Posts: 255

Bikes: Surly LHT (weekend ride & touring), GT Outpost (commuting), Brompton M6R (Weekend tours that involve flying), Co-Motion Periscope Torpedo (family weekend ride & touring)

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
FYI: The Lezyne o-ring size is 22mm (inside diameter) x 28mm (outside diameter) * 3mm (thickness)

Advanced Autoparts sells that O-ring. The item number is 64622.1 and cost just a little over a dollar.
cbike is offline  
Old 04-05-18, 09:20 AM
  #10  
pdlamb
Senior Member
 
Join Date: Dec 2010
Location: northern Deep South
Posts: 5,141

Bikes: Fuji Touring, Novara Randonee

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 934 Post(s)
Liked 17 Times in 11 Posts
Originally Posted by rmfnla View Post
Stupid me; I bought an Aieron pump from Performance for $13 about ten years ago and have never had a problem with it.

Of course, it's not a fancy alloy pump so I must be missing out somewhere...

I've thought about doing something like this, but since I'm 200 miles from the nearest Performance shop, it seems foolish. Any warranty issues would cost me twice as much as the pump to send it back.
pdlamb is offline  
Old 04-05-18, 04:29 PM
  #11  
rmfnla
Senior Member
 
rmfnla's Avatar
 
Join Date: May 2005
Location: La La Land (We love it!)
Posts: 6,330

Bikes: Gilmour road, Curtlo road; both steel (of course)

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 268 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by pdlamb View Post
I've thought about doing something like this, but since I'm 200 miles from the nearest Performance shop, it seems foolish. Any warranty issues would cost me twice as much as the pump to send it back.
Well, it's three years since I posted that and the pump is still going strong, so I'm not really feeling too foolish about it...
__________________
Today, I believe my jurisdiction ends here...
rmfnla is offline  
Old 04-06-18, 07:44 AM
  #12  
pdlamb
Senior Member
 
Join Date: Dec 2010
Location: northern Deep South
Posts: 5,141

Bikes: Fuji Touring, Novara Randonee

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 934 Post(s)
Liked 17 Times in 11 Posts
Originally Posted by rmfnla View Post
Well, it's three years since I posted that and the pump is still going strong, so I'm not really feeling too foolish about it...


Perhaps I should have added to my original post that a couple of the recommendations I've seen for Performance house-brand pumps were from people who'd had two or three warranty replacements. After my disastrous experience this winter with "faux suede" gloves, I'm ready to put Performance into the Walmart bin: OK for brand names, house brand apparently made as cheaply as possible.
pdlamb is offline  
Old 04-06-18, 09:28 AM
  #13  
rmfnla
Senior Member
 
rmfnla's Avatar
 
Join Date: May 2005
Location: La La Land (We love it!)
Posts: 6,330

Bikes: Gilmour road, Curtlo road; both steel (of course)

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 268 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by pdlamb View Post
Perhaps I should have added to my original post that a couple of the recommendations I've seen for Performance house-brand pumps were from people who'd had two or three warranty replacements. After my disastrous experience this winter with "faux suede" gloves, I'm ready to put Performance into the Walmart bin: OK for brand names, house brand apparently made as cheaply as possible.
Yeah, a lot of their stuff is sub-standard.

I got lucky with the pump...
__________________
Today, I believe my jurisdiction ends here...
rmfnla is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.