cs1

Did a search and couldn't come up with anything. I'm looking to paint an old Zefal frame pump hpx and need a little help on disassembly. Any diagrams or instructions out there?

Tim

jacksbike

At the pump handle end, you have a black or silver threaded piece that holds the shaft into the body. Under that, I believe you have a long spring. At the valve stem insertion end: First a large black or silver approx. 1/2 wide medal threaded cap. Under that,if you are set up for presta , there is a black rubber 1/2 " thick spacer, followed by a short spring and washer. Schraeder is the black rubber spacer, a small black cone shaped spacer , than the spring and washer. Not sure if the lever comes out, but if it does there should be a small threaded nut on the end holding it in. Best thing to do, obviously, is to disassemble everything in order , and draw a picture of all as you take it out. I may not be 100% on this, but I hope that this wll help.

cs1

I've figured out the black plastice part on the main body. I was wondering how to get the pump head off the other end of the main body. It looks like a screwdrive would do but it would have to be 14"-16+ long to fit into the body.


Tim

jtdehait@qwest.

Yes, a long screwdriver or a 1/4 in ratchet, extensions, and flat blade screwdriver head. You could make one out of a rod with a flatted/filed end.

Anyone know how to disasseble the handle end of the HPx?

cs1

You are late to the party @jtdehait@qwest. But thanks for getting back. I just want take it apart to paint it.

Homebrew01

You've had 9 years to work on it. Any luck ?

jtdehait@qwest.

So, do you know how to disassemble the handle of an HPX?

jtdehait@qwest.

So, do you know how to disassemble the handle of an HPX?

leob1

The last time I saw my HPX it was about to go under a truck tire. I had to cover my eyes. Good bye old friend.

jtdehait@qwest.

Do you still have the pieces? Could you take a look at the handle and see how it comes apart?
Thanks
Jack

fietsbob

handles are on the plunger there is a threaded ring to remove the plunger.. from the barrel

as I recall the handles were fixed to the plunger in the factory while it was manufactured ..

though the last one I've seen was 25 years ago so memory has faded some..

79pmooney

I too would like to be able to take the handle end apart because one of my HPXs and my new Classic both have handles that rattle on less than perfectly smooth roads, sounding just like loose headsets. Or maybe someone here knows how to stop that rattle.

I make the rattle a little better by reducing the vibration transmitted. Both pumps are mounted on brazed on headtube pegs. I cut a say 10" x 3/4" strip of inner tube and stretch the strip over the pum end, holding the handle and stretch strip with my left hand as I put a 1" wide tight fitting innertube ring over the last inch of the handle. Last, I cut the stretched strip with scissors and let it slide back out of sight under the ring. With black pump handles, you don't even see the innertube and it makes the mount much more secure and quieter.

Now if I could just get the pump itself to shut up!

Ben

fietsbob

Pour in epoxy? use a padded pump strap or 2 to secure the pump to the frame..

I use a twofish strap to keep my Silca Impero from falling off ..

add some inner tube sourced tubing over the pump , that will slide off easily when you need a pump to pump.

leob1

Sorry it was a few years ago, and I was not going into traffic to retrieve the, very flat, remains.

Miele Man

I just looked at my Zefal HPX and i see 2 notches on the inside of the pump handle. i don't know if that unscrews (I think it does) or if it's a press fit.

Do you really need to take it apart (and risk breaking something) just to paint it/

Cheers

jtdehait@qwest.

The two notches inside the handle don't seem to allow it to unscrew. The plastic pieces inside the handle are split in two, so they may be a press or snap fit. As you say, I don't want to break it, so I'm looking for someone who has disassembled it or has a broken one to inspect.

I'm in the process of turning a #4 into a #3 length - in polished Al. I have the option of shortening the inner rod at the seal end, or inside the handle. Inside the handle would be neater, and give me the option of dampening the vibrations of internal parts to stop the rattles.

Removing the pump head was easy with a homemade long screwdriver made from a 3/8 rod with the end ground down. The front grip removes easily with GooGone dribbled into it. It softens the glue (after about an hour), allowing it to be pulled off.

Next up is shortening the barrel, but saving the rounded end and hex hole, and machining a sleve plug with the same internal volume as the rounded end (wich sets the max pressure it will reach). Then it gets JB Welded together. Sounds like a lot of work for a $40 pump, but the engineering challenge is where the fun is.
Jack

cs1

LOL, don't feel much smarter!

JaccoW

Time to necro this thread with an update and some pictures!

I bought an old HPX size 4 a while ago for very little money and I too wanted to dissasemble it to polish everything.
So let's tear it apart to figure out how it works.

As several have mentioned before, the inside of the pump handle has two notches. Don't bother with those. My guess is they use two parts to slide it in there instead of making it out of a single piece. No amount of turning seems to do anything.

What you should be looking at is the cap that switches between modes. It is made of a very tough plastic (probably nylon or something) and is held together with a small barbed piece in the switch itself.
The switch is a single piece connected to a long square rod that does the actual switching.

I decided going the heavy handed approach and grabbed a locking plier. Lock it around the switch tightly and just leverage it down, as if to break it off.
(Don't forget to put some protective layers around the plastic switch or you will scratch it up.)
I had the head at a 45° angle at some point and then it just popped off.

Do not twist it around. It will round off the square rod and make for a sloppy feeling switch.

The barbed piece will have popped out and you can use a small screwdriver or a corkpuller to take it out entirely.

Clean and polish everything you want and put everything back together. Push the barbed piece in using a screwdriver of something similar and you're done.
My suggestion would be to compress the pump in its X-mode or to scratch something to make it clear where to put it. Then again, it probably doesn't matter where you put it as it is a square switch anyway.

Pictures:




Good luck!

P.s. I have a brand new HPX on the way and I will try repeating these steps on that one. See if the steps can be reproduced.
I can make a short video of it if people are interested.

cs1

JaccoW

And yet I found numerous people interested in doing this. Some ended up polishing just the tube, others combined it with classic chromed parts but in the end nobody made an actual guide out of it.
Since I have a tendency to buy brand new stuff and take it apart to do some foolish thing with it this was a perfect opportunity for me to get my hands dirty.

I just hope some lost soul runs across this thread in the future when they have the same question.

SurferRosa

I recently saw a youtube video on this pump.

JaccoW

For those interested:

Disassembled head. The silver screw in the bottom is what you have to unscrew with a long flathead screwdriver (or extensions) to take off the handle.



With the exception of the plastic switch and the replaceable plastic inserts on the pump head everything is basically metal (aluminium)

I'm not done yet but I have a brand new one that I want to properly dissasemble and polish (+clear coat) so I'm not putting too much effort into this one.

jspicker

Does the handle come any further apart? The weight seems excessive and I would like to remove whatever is in there and just have a compression spring in the handle like and old Silca frame pump.

seedsbelize 

Timely
Mine pumps just fine, but when I compress it to mount on a frame, it sticks in compression mode. It needs more space and a more violent pull to unstick it. Have you figured out how to get that part out? Just inside the handle at the end opposite the switch.__________________

JaccoW

Doesn't seem like it does. It is a sandwich of aluminum and plastic that houses the mechanics to slide it into HPX or compression mode. I might be curious enough to saw it open and take a look inside but I don't think so. Besides, it would mean it was permanently stuck in compression mode and that's not great for pumping.​

You could try pulling out the plastic bit on the end that switches between modes. It might just be rounded off or something. Contact Zefal for a replacement if necessary.