A lot of unexpected movement can be traced to the rear triangle clip set up as there is quite a bit slack in it. I soon learned that this is normal for Bromptons. I have several times thought that my headset has loosened when pushing it then applying the back brake. Usually when I start using it after a spell of using my other bikes. Pushing it then applying the front brake soon reassures me that all is well.
An actual bit of wear has existed in the rear triangle hinge since I bought it though a small amount of play seems to be considered acceptable. After all, it was bought used, with an unknown history. It's not something that was noticeable when riding. More recently though I've been thinking that for peace of mind, I'd like to get it done, as though my Brompton isn't immaculate, it's nice to know that all the mechanical parts are sound.
As I was looking at a non-Brompton folder in a branch of
Halfords I brought the subject up with a chap from the workshop. He was quite down to earth. He said that none of their customers had needed to get their rear hinge done yet. He admitted that it was quite possible that it was because they'd not been a Brompton dealer for long enough for there to be a demand for it. ie, none of their customers had worn one out yet. The specialised reamer that Brompton recommends wasn't something that was part of their tool kit, in this one or any other of their 400 stores.
I said that I thought that was a rather circular argument, if you couldn't do the job then you wouldn't get customers asking you to do it. He said that was their position at the moment, it could change in the future.
After looking into it on line and looking for the specific tool the best I could find was on Amazon for £50 or so. The parts kit seems easily available for £24.00. Normally I would have a go at something like this myself but in this case I'd rather leave it in the hands of someone who'd done a few previously. After ringing round I realised that I was living in a bit of a Brompton dealership desert but eventually got a response from The Bike Factory, Chester. (I have no connection with this company. I just include it here in case someone else in the area is in the same situation). Booked in about a week in advance, done the same day. Cost, £47.00 which seems reasonable to me. I asked if they got many of these rear hinge jobs in. The reply was that they came in batches, they might have nothing for months, then several in a short time.
Interesting to see their stock of Bromptons, including the 12 speeder. Ooo! shiny bikes! Must. Resist. Temptation. Readers will have realised by this point that I obviously don't get out much, certainly to bike dealerships, anyway.