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I first came across this idea on here a year or so ago on this thread, where forum member Mrlinderley came up with a clever way to fit a small Lezyne pump into his steerer tube.
I loved the idea, but it was a bit too high effort for me to ever do it myself...
However I’ve now come up with a simple (and cheap) alternative to this idea, so I thought I’d share it.
Recently I saw that Lezyne had released a new even smaller pump, so I thought I’d see if this had made it easier to store it in the steerer...
In short, yes it had, and the pump fitted nicely inside my steerer tube (fork is a 2018 Pike) with no need to fiddle with the star nut.
So all I needed then was something to plug the hole and keep it in there. The first obvious idea for this was the Fork Cork, but although it looks like a good product it seems a bit overkill to me - surely a well-sized rubber bung would do the job at a fraction of the cost…
After some searching around online I discovered these rubber kayak bungs on eBay, and with a bit of modification to fit the fork nicely it was looking good.
Finally, I was getting a little rattle from the pump but that was solved by simply wrapping an elastic band around it, and it now fits snuggly with no movement.
Here’s some pics:
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I was of course a little worried the bung might move over time, but it’s a tight fit and a full day of testing at BikePark Wales has confirmed that it does not move at all even on the roughest terrain.
Also, worth noting that if you prefer to carry CO2 rather than a pump then a standard cartridge will also fit in there, as long as you have a compact inflator head on it.
Hope someone finds this useful, P.
Like!
Love it.
Great idea! I'll have to see if my pump fits.
The pump has to be pretty tiny - I've not seen any other models that will fit.
Bookmarking.👍
Neat idea.
Does it sit like centered in the plastic cup(what about the top) so it doesnt rattle about in there 😕
The pump is almost the same diameter as the inside of the tube, there's probably 1mm gap all round at most, and the elastic band takes this up perfectly so it fits quite snugly with no movement or rattling.
That's really clever 👍👍
Daft question are kayak bungs all the same size? Or did you order a specific size?
The pump has to be pretty tiny – I’ve not seen any other models that will fit.
Yup, it's the Lezyne Pressure Drive I have so too big sadly.
Might be an idea to write out a few birthday cards; you'll be a long time out in the wilds with such a tiny pump.
Solution looking for a problem given that most mountain bikers take more luggage than I would take to the USA.
I’ve got a co2 cartridge and inflated up mine. Wrapped a couple of strips cut from an old esi grip around the cartridge and it doesn’t rattle or move.
When I first did it I just raped over the bottom of the steerer but now it’s got a fork cork fitted and I’ve added a plastic tenner and a quick link. Along with Saumarai bar end tubeless repair kit and a Swat tool on my bottle cage for quick blasts it means I don’t bother carrying any other tools or spares.
When I first did it I just raped over the bottom of the steerer
Ooft, make sure you deburred it first.
I've just ordered some to fit a 18650 battery for my commute light in the steerer.
Section of inner tube might look a little tidier than an elastic band
Daft question are kayak bungs all the same size? Or did you order a specific size?
Yeah there are a few sizes, I ordered 38mm which seems to be the most common size.
I had a similar idea, didn't like the price of the ForkCork so after a few measurements went for a 32mm drain plug from a boat for £7.
https://www.ebay.co.uk/itm/153650497785
Flipping the handle 90deg causes the bung to expand in width to give a very secure fit. Probably a little bit heavier than your kayak bung.
I had a vague plan to give it a good name, some marketing spin and little bit of engraving and flog them as the next must have accessory for less than the price of the competition but never got round to it.
Sounds like a good idea!
Great idea, but only if that tiny pump is any good. I got a 100cc oneup pump after discovering that my little pump was utter crap when trying to inflate a wide MTB tyre.
Super!
v2.. imagine a thread in the "+" part of the bung that the head of the pump screws into.
Pull the plug out and the pump is fixed to it.
Piece of roadie innertube to replace elastic band as they can deteriorate, apart from that it's a genius hack or bodge, send it in to GMBN.
Nice one, I have the pump and I thought it was surprisingly good for the size.
I approve of this hack. good work
Great idea
Have you used it to actually pump up a tire? I love the idea but worried the pump would be a bit useless
Lots of questions about the pump, so I just went and tested it out...
I let down my tyre completely, which is a Specialized 29 x 2.3 (not the biggest 2.3 out there, but pretty chunky).
It took me 2mins 20secs to pump it back up to the pressure I would want to ride it at.
I was pumping fast but it wasn't hard work at all as there's very little resistance on a pump this small.
My conclusion is that it's totally useable as an emergency pump on the rare occasions I need it (which is thankfully very rare these days since going tubeless). I'm actually pleasantly surprised by its performance.
If I was doing a race I'd simply swap it for a CO2 inflator for the day I think.
That doesn't seem too bad at all.
I've been at it with the rubber kayak bungs again... this time with a smaller size bung which can fit in the axle.
I've butchered a tyre repair tool and combined it with the bung to make a quick-access tubeless repair tool.
Works really well for this!
I'm thinking the same for my seat post (benefits of not having a dropper). Hmm...
Presumably this would work on a straight steerer as well?
That is a good idea.
This is a good idea..but... What's wrong with using a strap (MANY, many are available...BPR, Dakine etc) and simply strapping a (cough) better) pump to your frame?
Or even getting a one-up pump/tool, and just clipping that next to your bottle cage?
DrP
My main complaint with strapping things onto my frame is that they get caked in mud and require regular cleaning.
They also aren't particularly aesthetically pleasing 🙂
I take your point though - it's only a marginal improvement really. But an improvement none the less.
Top hack 👍
Strapped stuff also has a tendency to fall off when you don't notice and as pointed out gets caked in crap.
One-up is the same solution but £££
What's wrong with Lezyne pumps? Last one I got a shot of was brilliant.
Hmmm...anyone tried the "pump stashed in the steerer tube" hack on a road bike?
I have no idea of the internal diameter of my Giant TCR steerer but I'm now curious!
Great idea. I’ve toyed with the idea of a bing but always been too lazy to try. Imaging how much more useful the space would be if we’d stick with 1.5 head tubes?
I have no idea of the internal diameter of my Giant TCR steerer but I’m now curious!
You’re going to be disappointed when you go looking for a hole in the bottom of the steerer
Can't wait to try this as I doubt I'll ever not carry a pump due to worrying about messing up a co2 fill lol.
This would be a way of carrying an emergency pump without taking up space in my bags or on the frame
Cheers, great hack
Interesting idea.
Is the bung just held in place by friction?
What happens if the bung works its way out and the pump drops - could it get jammed in the tyre knobs and effectively act as an instantaneous brake? If so this is extremely dangerous. If not it's brilliant.
If it's a possibility i'd be looking to add some form of positive retention - zip ties or similar maybe?
It was these ones for the cranks, in the smaller size.
As you can see from the pics I had to trim them down quite a bit to fit the Sram dub cranks.
Is the bung just held in place by friction?
Yes. It's a really tight fit though, and the pump is really light so there's very little force trying to move the bung.
As I said I rode it hard at Bikepark Wales for a day and it didn't move a mm, so I am confident it won't move.
Don't think there's any risk of the pump jamming the front wheel, even if it did fall out.

