Brompton Seatpost Sleeve - Full procedure

How to replace the Brompton seatpost sleeve from start to finish with close up view of reaming tool and process. This is typically a service centre job.

[@capeman10]

Very nice of you to share your knowledge here with the community, Thank you.

[@bromptonair3126]

Thankyou, appreciate your feedback. I hadn't realised that viewer comments were being queued for my review ! I have activated them to appear automatically now

[@kjm-ch7jc]

Looks like Brompton made it that way so only a dealer could do that job, looks easy but the cost of the reamer makes it uneconomical.

[@bromptonair3126]

I agree about the official Reamer but most workshops have a set of reamers which could be used

[@iant5222]

liked it... you are a quick, clean, clear, efficient worker covering a subject I needed to know about .I wish there were more chunks of meat like this in the thin youtube soup

[@bromptonair3126]

appreciate the positive feedback, wish I had more time to do videos it was a fun

[@chrislabish]

Thanks, we’ll done video. I may try using a regular shorter industrial 32mm reamer and attach it to a home made extension to keep it aligned. What size diameter is the mandrel?

[@bromptonair3126]

Eyeballing it I would say 31mm . It appears to be a 32mm tube that has been turned down to 31mm for most of its length. I will update when I find my calipers !

[@javiervaldivieso83]

Can you put the website where you bought the complete tool? The reamer and the piece that you turn by hand. I can not find it anywhere. Thank you.

[@bromptonair3126]

I bought it from www.rjmstar.com in Dubai (QSTSLV-REAMKIT)

[@uvvos7837]

At the end of the video you mention that you will be doing more vids, what are you planning to cover ?

[@bromptonair3126]

I am building Brompton e-bikes and will cover the process. My main project is to create an e-Brompton Air , an electric Brompton that can travel on an aircraft, it needs to be less than 23kg in a case and the batteries acceptable for cabin. Probably I will use power tool batteries. The second project is to create a 50km/hr e-Brompton using a home made 52v battery pack.

[@Spludda]

Do you know the diameter of the mandrel? Assuming it’s not tapered any tube of the same diameter could be used?

[@bromptonair3126]

It appears to be a 32mm tube that has been turned down to 31mm for most of its length .

[@Spludda]

Do you know where I can buy the reamer tool in the uk? A web search didn’t show anything.

[@bromptonair3126]

the original manufacturer is www.metalbor.com (its a Trubor brand) , or any Brompton dealer can order for you QSTSLV-REAMKIT ) or I suspect you can get any 32mm reamer that is long enough to fit through the bottom tube

[@Teslawaverunner]

is there a way to replace the sleeve without having to use the special tool ?

[@bromptonair3126]

Brompton don't seem to offer pre-reamed sleeves any more. I did see some for sale on ebay, typically from Hong Kong sellers. I have several Bromptons and am experimenting with different seatposts, so decided to buy the special tool ('reamer') and some spare sleeves, that way I can always have a good fit. Many years back I damaged a frame because I overtightened the clamp rather than replace the sleeve, had to replace the frame !