I need to inflate my Brompton's tires. I tried to use my Joe Blow floor pump but it was pretty much impossible to get it to go over the valve due to the size of it and needing to get around the spokes. I've seen some people recommending a Lezyne Floor Pump, but there are lots of them out there and I'm not sure which one to get for a Brompton. Some forums recommend a Lezyne for Brompton but I can't find that anywhere. Does anyone have suggestions for specific products?

Also, I tried inflating the rear tire while the bike was fully unfolded and the bike kept slipping and crashing to the ground even though I had it propped against a wall (I don't have someone to hold it for me). I then tried folding in the rear tire so it's in the "kickstand" position, but then the tire keeps rolling forward when I try to attach the valve. Is there an ideal way to position the bike when trying to inflate the rear tire? I don't want to keep dropping it to the ground as you can imagine and am at a loss for how people are doing this. Videos on Youtube don't seem to address this.

Thanks in advance for any guidance.

First, chock the wheels, use some sticks or a couple of rocks it can't roll and fall over. I use a Giant branded floor pump air tower 0 or something..Silca Tattica works fine , Topeak road pocket rocket also.

On kids bikes (14"), I use a traditional flexi hose connected to the foot pump because I got tired of hitting my fingers on cogs of frame as I unplug the pump.

Alternatively, if you can fit schrader valved tube, then you can fit bent extension which make life easier

Are these presta or schrader valve tubes? If presta, are they extra long valve stems? I know the wheels on a Brompton are small, but with typical pumps having a 90 degree head, I can't see the difficulty you are having.

If the bike is not stable stood up, lay it on its side on the floor. Or fully fold it, both tire valves should be accessible.

My memory is faded a bit, but I once had a stroller/trailer/kids bike type tire that was too small for my pump to hook on to. I took it to the bike shop. They had to look around for the tool because they didn't use it much, but they found it and pumped up the tire. Once I saw what they used, I picked one up at Home Depot on the way home - it was some sort of adapter for a regular pump.

Brompton mount Schrader valve tubes.

They are Marathon Plus 16x35 so should be schrader. I was able to get a small Topeak hand pump to work to some extent but it was nearly impossible to get them fully inflated with that, and I can't see what the PSI is with that pump. I had a Brompton previously (that I later sold) that came with a pump but not this one and the Brompton pump is a little expensive at ~ $40.

Your comment was so helpful! I think I figured out what you're referring to. For schrader valves, it's called a "90 degree valve extension". This looks like what I need - thanks!

Gosh I'm looking online at a Brompton pic, and I can't see the issue, it looks like plenty of radial clearance (between valve stem and hub), unless it's laced with spokes crossing the valve stem? Or do you mean circumferential clearance (along rim) to adjacent spokes? Is the pump head that large? Those valve extensions are designed for truck and trailer tires, and may throw your wheel off balance, if left on.

The pump head on his pump may differ from what is typical. On some Bromptons have less vertical space due to dynamo or e-motor.

Ah. Front dynamo should be smaller flange than the rear hub, but a front motor on 349s, yeah I could see a lot tighter fit. Good call. I couldn't figure out for the life of me what the problem was. Pump heads aren't that big, unless no 90 degree head, the head is coaxial with the pump tubing?

This hose adapter works great for the Brompton:
https://www.amazon.com/gp/product/B07MXBYPT2
It is easier to use than the right-angle valve adapter.