# Seat post sleeve



## chris folder (2 Aug 2018)

Hi anyone ever fitted a seat post sleeve on your Brompton? My seat post keeps slipping i have tightened seat post clamp up very tight cant tighten it up anymore and still slips when rideing. So will have to have a new sleeve fitted in the frame if you have fitted one yourself how is it to fit and what glue did you use?


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## 12boy (2 Aug 2018)

I tried DIY but failed. Used superglue for the sleeve and that worked but the sleeve was too big inside to allow the seatpost to pass. So I took fine sandpaper on a thick dowell amd sanded until it would pass and then had to tighten it way too much. My rear triangle hinge was also toast so I made a box, sent the bike to a dealer in Minnesota and they reamed the new insert and replaced the bushings and sent it back. My overtghtening the seatpost had ovalized it so a new one was in order, also. Works great now. If there is one thing I do not love on the B it is that seatpost arrangement. I have owned a lot of bikes and have refurbished some that had frozen seatposts but this was the worst seatpost PITA I have ever encountered. Don't know if the ream was truly necessary but my suggestion is pay a reputable shop to fix yours. Just wasnt worth the aggravation to do it myself.


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## reppans (3 Aug 2018)

I found my seat post slipped due to skin oils from my hands when I grabbed the seat post to fold. Try removing the seat post and wipe it down with alcohol, including the mating surfaces of the plastic sleeve inside the seat tube. Then don't touch the seat post anymore and only fold the rear wheel by lifting the saddle.


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## Rooster1 (3 Aug 2018)

I used a cut up coke can on a road bike as a shim, it's still working two years later.


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## mitchibob (3 Aug 2018)

I think it's really important not to over-tighten the clamp, as on my first Brompton, putting a little too much into the seat-clamp stopped it working properly at all, and was replaced a few days later. I actually bought a cheap titanium seat post for my newer brommie this year, and while it's Brompton 'compatible', it lacks the finesse of a decent Brompton part (i.e. you can pull it straight out as it's not flanged at the bottom), but it's 300g lighter, and little more comfy and doesn't tend to slide much, once about a half turn was added to the seat post clamp nut, although, perhaps due to super firm suspension (near non-existant), I do have to stick an additional quarter turn in about once a month perhaps.


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## chriscross1966 (5 Aug 2018)

It's a service spare that really needs the shop to fit. If its slipping your first thing to do is thoroughly clean and degrease the post and the liner. I go through a liner every 2-3 years or so.


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## chris folder (5 Aug 2018)

Hi guys ok  i see you can buy the seat post sleeves but hard to fit them yourself i spoke to a Brompton dealer he said they need to fit them as it needs to be reamed and they have the tool for doing it. Chris when feel you need a new sleeve fitted have you got your seat post clamp nut screwed on quite alot from when the sleeve is new?


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## chriscross1966 (7 Aug 2018)

Not really, i use knurled nuts and do not expect it to be more than hand tightwhen open and not to take a lot of effort to close. When it starts to drop when riding and cleaning doesnt fix it i replace it. You need a 32mm reamer and rubberised superglue that needs to be refrigerated, its also important to clean the old glue off too. If you know what you're doing it takes about an hour. My first one took nearly four.


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## TheDoctor (7 Aug 2018)

What others have said - try degreasing the seatpost first. I had exactly this problem, and a good wash with Mr Muscle did the trick.


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## smutchin (7 Aug 2018)

mitchibob said:


> I think it's really important not to over-tighten the clamp



This. Very much this.

As @chriscross1966 says, when the seatpost starts slipping, the solution is to get the sleeve replaced. Tightening the clamp will only make it worse in the long run. DAHIKT.


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## Beter Poutakis (9 Aug 2018)

It hasn't been quite a month yet since picking my Brompton. The seatpost recently began to slip. Reading this thread, I've only 'slightly' tightened my clamp. Problem resolved... for now.


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## chriscross1966 (12 Aug 2018)

Beter Poutakis said:


> It hasn't been quite a month yet since picking my Brompton. The seatpost recently began to slip. Reading this thread, I've only 'slightly' tightened my clamp. Problem resolved... for now.


Check it with a torque wrench once you've cleaned it ... most new owners don't have a visceral understanding of how clean the seatpost needs to be, I certainly didnt.


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## TheDoctor (17 Aug 2018)

Me too.
I try to avoid touching the sestpost for that reason.


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## rogerzilla (25 Aug 2018)

Easy enough job. Break the old sleeve out and clean up the seat tube. Get the new one (mine came as a pair;; if so,, try them without glue and use the one that works best).

The glue I used was Unibond Repair Extreme Power Glue (Wilko sell it). The sleeve did not require reaming afterwards.


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## dagtontv (28 May 2019)

rogerzilla said:


> Easy enough job. Break the old sleeve out and clean up the seat tube. Get the new one (mine came as a pair;; if so,, try them without glue and use the one that works best).
> 
> The glue I used was Unibond Repair Extreme Power Glue (Wilko sell it). The sleeve did not require reaming afterwards.



rogerzilla

My saddle is beginning to slip and move rather too easily and I need to get it replaced. It sounds as if you were able to remove the old sleeve cleanly enough, any special tools required? I have made other repairs to my Brompton how long will it take?

dagtontv


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## rogerzilla (28 May 2019)

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


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## chriscross1966 (30 May 2019)

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.


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## Schwinnsta (8 Jun 2019)

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.


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## Fields Electric (2 Jan 2020)

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.


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## u_i (2 Jan 2020)

If the glue that needs to be removed is a superglue, it dissolves with acetone.


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## roley poley (5 Jan 2020)

rogerzilla said:


> 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


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## Fields Electric (8 Jan 2020)

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?


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## 12boy (8 Jan 2020)

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.


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## Fields Electric (21 Feb 2020)

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.


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## 12boy (21 Feb 2020)

Good for you. That is a job I'd find intimidating.


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## rogerzilla (23 Feb 2020)

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.


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## rogerzilla (24 Feb 2020)

Fields Electric said:


> 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.


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## Gunk (24 Feb 2020)

Fields Electric said:


> 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 🙄


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## Fields Electric (6 Apr 2020)

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.


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## rogerzilla (6 Apr 2020)

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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## Fields Electric (8 Apr 2020)

Thanks, there may be about (1/16") just enough to make a tapping noise. But I know what the cause is now! That's measured at the top suspension bush. There was definitely (1/4") before I replaced it.


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## tribanjules (8 Apr 2020)

Big shout out to Brilliant Bikes.
Received my saddle height I sent with this lovely note !


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## Gunk (8 Apr 2020)

They always give you a smiley face doodle on the invoice, a genuinely nice business to deal with.


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## roley poley (8 Apr 2020)

I have had the same, they are my go to supplier and have an attitude and ability missing from many .Have a ewechewb channel to peep at too


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