Brompton suspension block (title changed from 'newbie questions ')

[a.twiddler]

Mine is a standard block and doesn't bob or squeak though I'm only 80 kilos. To make up for it the 3 speed rattles and a strange clucking sound appears and disappears at random. The hub generator makes irritated sounds from time to time too. Everything works, nothing is loose or has fallen off. So if it ain't broke I'm not going to fix it. I'll just accept that it's just one of those Brompton peculiarities, and live with it.

 

[Tenkaykev]

Mine is a standard block and doesn't bob or squeak though I'm only 80 kilos. To make up for it the 3 speed rattles and a strange clucking sound appears and disappears at random. The hub generator makes irritated sounds from time to time too. Everything works, nothing is loose or has fallen off. So if it ain't broke I'm not going to fix it. I'll just accept that it's just one of those Brompton peculiarities, and live with it.

I had a noise that puzzled me for ages. I used to become aware of it when cycling along quiet country lanes. It can be best described as the faint sound of a turbine ramping up, heard in the far distance, one of those sounds that doesn't appear to come from any identifiable direction. It turned out to be the wind playing on the spokes of the wheel, the penny dropped when I realised that the sound got louder whenever I passed a wall or hedgerow.

 

[berlinonaut]

I have the Joseph Kuosac rear block (...) It is a LOT stiffer than the old FIRM block that was fitted to mine. I like it. YMMV.

The old standard blocks are too soft for my liking. Pre 2008 block got a jubilee clip around it, post 2007-pre 2018 standard block got exchanged for the "hard" version on the Bromptons I ride the most. The standard block works ok-ish, but I like the hard version better. Post 2017 factory standard block is fine for my liking. Joseph Kuosac block is way to hard for my liking.

 

[robjh]

Just changed the title of this thread as it's now developed into a useful discussion of the compression block, of various hardnesses.

 

[rogerzilla]

I had a jubilee clip around the Brompton "firm" block (two clips around the 2008 standard block) but the JK block is noticeably harder still.

 

[berlinonaut]

I had a jubilee clip around the Brompton "firm" block (two clips around the 2008 standard block) but the JK block is noticeably harder still.

I think it was Steve Parry who invented the use of a jubilee clip on the old Brompton suspension block, back in the 90ies (see i.e. here: http://www.foldsoc.co.uk/spnews.html). I cannot imagine that a jubilee clip would work well on the newer blocks between 2008 and 2017 (and @Kell reported back after trying that they would indeed not make any difference) So I am interested in what you noted.

 

[Fab Foodie]

I found with my new 2 speed that the block firmness simply didn't work with my Brooks saddle in thet it felt like a suspension system that was set-up all wrong. Stuck a firm 'Spoon' saddle on the bike and all feels well.
The Brooks works a treat on my 6 speed where I have some kind of rock-hard titanium spring thingy....

Hi @robjh long time no see, hope all is well?

 

[Kell]

I think it was Steve Parry who invented the use of a jubilee clip on the old Brompton suspension block, back in the 90ies (see i.e. here: http://www.foldsoc.co.uk/spnews.html). I cannot imagine that a jubilee clip would work well on the newer blocks between 2008 and 2017 (and @Kell reported back after trying that they would indeed not make any difference) So I am interested in what you noted.

True.

I did try it after ‘some bloke on the train’ said that he used to do it on his.

As mentioned, I tried it but my findings were…

1) I couldn’t detect a massive difference. I think in order for it to really work you’d need several. It just seemed to bulge around the clip.

2) Because it bulged around the clip I felt that continued use would eventually cause it to cut into the block and split it.

The Kuosac block does suit me better. But I’m also now of the opinion that making the rear end that hard may also have contributed to my seat post having a slight bend in it. If there’s no flex in the rear end, then I guess the seat post takes the brunt of it.

 

[robjh]

Hi @robjh long time no see, hope all is well?

Hi Fabs, I'm well thanks. I've just joined the Brompton club for a month of interrailing next year, hence my daft questions about these small-wheeled bikes. When I got it I couldn't even work out how to unfold it!
Hope you're both well too - I was enjoying (and sympathising with)your post about runaway whippets on another thread 😄

 

[Fab Foodie]

Hi Fabs, I'm well thanks. I've just joined the Brompton club for a month of interrailing next year, hence my daft questions about these small-wheeled bikes. When I got it I couldn't even work out how to unfold it!
Hope you're both well too - I was enjoying (and sympathising with)your post about runaway whippets on another thread 😄

Ooo lucky you! Sounds a great trip!

All good here thanks, slowly getting the house sorted, finding some cycle routes, and still searching for my climbing legs!

 

[mitchibob]

JK Super-firm suspension block with cheap titanium seat-post has been great combination for me. But going back to OP, that block definitely looked like it'd done some work, and spongier than it should be, so even standard firm block might be better. Thankfully, these are cheap easy replacements. But you can get exotic with them too ;-)

 

[robjh]

An update on this thread. I've just fitted a new 'standard' firmness block, and the improvement is striking, and just what I was looking for. It no longer feels like the bike is trying to fold up underneath me at every bump in the road.

 

[mitchibob]

An update on this thread. I've just fitted a new 'standard' firmness block, and the improvement is striking, and just what I was looking for. It no longer feels like the bike is trying to fold up underneath me at every bump in the road.

Great news! Cheap and simple!

 

[robjh]

Great news! Cheap and simple!

Indeed. CycleChat to the rescue again!