Seat post sleeve

I broke the old one out with a screwdriver. There will be bits of old glue left behind, and you need to remove as much as possible with a scraper of some sort. If you can actually buy the new seatpost sleeves - Brompton don't allow many parts to be sold to the public these days* - you get two in a pack. One has a locating lug and the other doesn't, and you need to use the one that fits your frame best. I used Unibond Extreme Power Glue to stick the new one in and it worked perfectly without reaming..

*to maintain profit margins for dealers, I assume,but a very customer-hostile approach, especially as people who live outside London probably need a car to take the bike to their nearest dealer, if there is one within reach at all
 

chriscross1966

Über Member
Location
Swindon
I find a great tool is an old seatpost. Takes out the old sleeve if you invert it and tap it in from underneath as the flair on the post gets behind the sleeve and pulls it evenly off the frame. Then when you need to hold the freshly glued but unreamed sleeve in place you tap the seatpost in top down from the top. Cross drilling it about six inches down makes it easy to judge if you are in far enough and allows the use of a longish bolt or a bit of steel bar as a handle to get it in and out.
 

Schwinnsta

Active Member
Should not the first sentence read that the seatpost pushes out the old sleeve? Or rather tap it out all the way? I was lost completely on the second sentence. Some one should do a video of this.
 
Just Replaced mine. After some advice from a Bike shop, they advised that seat clamp bolt was a tight as it could go. next time round I would need a new sleeve. But that they would need a months notice before they could book it in. So when the time came, I had a go at the job myself! After chiselling out the old sleeve. I used a piece of course emery cloth to clean all traces of glue, rust and loose paint from the seat tube. Placed the new sleeve in, without any glue. Then tried the seat post upside down. It would not even fit. So I took the sleeve out and sanded the OUTSIDE down and replaced the sleeve. Repeat this process, until the post fitted, but was tight. I will shall run it around for a few days, without any glue, to see how it goes. I shall remove again and sand any 'high spots'. I am looking to use Gorilla type super glue to glue it I place when I am happy with the fit. I suspect that gluing it to the tube ensures that the sleeve does not 'jam' when the seat is raised.
 

roley poley

Senior Member
Location
leeds
I broke the old one out with a screwdriver. There will be bits of old glue left behind, and you need to remove as much as possible with a scraper of some sort. If you can actually buy the new seatpost sleeves - Brompton don't allow many parts to be sold to the public these days* - you get two in a pack. One has a locating lug and the other doesn't, and you need to use the one that fits your frame best. I used Unibond Extreme Power Glue to stick the new one in and it worked perfectly without reaming..

*to maintain profit margins for dealers, I assume,but a very customer-hostile approach, especially as people who live outside London probably need a car to take the bike to their nearest dealer, if there is one within reach at all
if you watch the vid on youtube by Brompton air called.Brompton seatpost sleeve-full procedure ...you will be in a better place
 
Ok didn't watch the video. But a weeks commuting and the sleeve is no longer tight. Does not exactly fall under its own weight. But is workable. I have owned the machine for 3 years. The ODO states 4500 miles, 4th Chain coming up to 1% stretch, wheel rims are very grooved. My next job is the annoying rattle from the rear frame. Which I believe is the rear hinge bushes. I have a few mm of lateral play at the rubber suspension block. I have acquired a 3/8 reamer and a set of bushes on order. It looks like at this age, the whole machine it pretty much needs a complete refurbishment. Any thoughts?
 

12boy

Veteran
Location
Casper WY USA
Perhaps some parts do, most likely the rear hinge bushes. If your headset cones and/or cups are worn you may like a Chris King Gripnut cartridge headset. Not cheap but pretty much maintenance free. If you haven't already, check the bearings in the front wheel. You haven't yet said what you have...1, 2, 3 or 6 speed...I buy sprockets 3 at a time since the 12 and 13 tooth ones need to be replaced every so often and I must order them on line and it saves on shipping. I've also found Jagwire Elite cable housing best for my brakes since it is made with both straight and spiral steel reinforcement and seems to allow for easier cable movement.
I've not worn through any rims yet, but I live in the high desert and the roads are much drier here than yours. Good luck with the rear hinge bushing, since it seems you will be doing that yourself.
 
Finally took the time out to do the bushes. Tools: 4 mm hex key. Torque wrench. Range of screw extractors pipe wrench, tool to extract pedals from shaft. Standard 3/8 reamer. Threaded rod nuts and washers. Some sort of work bench also useful. The technique is to remove one screw. Jam a screw extractor in its place. Remove other screw. Use a bigger screw extractor to remove bushes. Use the threaded rod to press. The new bushes in. The trick with the reamer. Is to get it to both ends of the tube before reaming to size. The new shaft should be 'gas tight' in the new bearings. Apply thread lock. Tighten to torque.
 
I did it all except the pressing in of the new bushes and the reaming. The local dealer did that for a tenner (using the special Brompton reamer) since I'd done the hard work already.

He said not all bushes actually need reaming. He always tries the spindle in them first and sometimes it's just right.
 
The technique is to remove one screw. Jam a screw extractor in its place. Remove other screw. Use a bigger screw extractor to remove bushes. Use the threaded rod to press.
I drilled the heads off the old screws. It takes low revs and high pressure as they are stainless steel. Buy a few cheap HSS drill bits, use a hand drill (the egg whisk type). Put all your weight on it and turn the chuck by hand, not the handle. This avoids hardening the screws even more!

I got the old bushes out with an M10 tap and a drift from the other side. That was the easier bit.
 

Gunk

Über Member
Location
Oxford
Finally took the time out to do the bushes. Tools: 4 mm hex key. Torque wrench. Range of screw extractors pipe wrench, tool to extract pedals from shaft. Standard 3/8 reamer. Threaded rod nuts and washers. Some sort of work bench also useful. The technique is to remove one screw. Jam a screw extractor in its place. Remove other screw. Use a bigger screw extractor to remove bushes. Use the threaded rod to press. The new bushes in. The trick with the reamer. Is to get it to both ends of the tube before reaming to size. The new shaft should be 'gas tight' in the new bearings. Apply thread lock. Tighten to torque.
Sounds a doddle 🙄
 
On the Bushes. We are up to April and I can hear an annoying tapping noise from the bushes and spindle thingy. Perhaps I should have used the proper reamer. Not changing them just yet. 4700 miles.
 
How much sideways play is there at the dropouts, where it's magnified? A surprising amount is considered acceptable (1/4").
 
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