# Brompton M2R New owner - Questions about QR on seat post and folding



## bence8810 (23 Oct 2018)

Hi all,

I am brand new to Brompton's and brand new to this forum - 1st post here, sorry if I may sound silly.
I've been riding a Dahon Metro 2010 for about 3 years now, the reason why I bought it was so I could bring it with me to the small islands just south of Tokyo where I frequently go fishing / camping. The Dahon served me right but I always had my eye on a Brompton, not sure if it was the hype or the small fold that I wanted it but I am glad I got it. 

p.s. I am also a film shooter and went through a few cameras before dropping the extra $$$ on a Leica and never looked back - I expect the same will happen to the Brompton.

So - the 2 questions I have - again if I overlooked something please bear with me. I watched videos and read threads / manual etc, still unsure what to do.

First of all the seatpost clamp, the QR thing. It is plastic and looks surprisingly cheap for the amount of $$$ (or Japanese yen rather) I dropped on this bike. I am having a hard time finding the balance between the clamp not tightening down the sleeve strong enough so the seat post goes in gradually over bumps and over-tightening the nut so that even with the clamp open, the seatpost won't slide in for folding.

I noticed that the plastic clamp sort of rotates beyond the central nut, I assume the plastic isn't strong enough and when the nut is tight, it starts slipping / over-turning. Picture below. 
What do you guys do to sort this out? I read that adding an extra QR on the post will work but isn't the charm of the brompton simplicity and things just working out of the box? I read people sanding down the seat post etc, really not something I'd like to do as long as there is a better way like adding on a stronger lever / clamp that won't slip etc. 





Second is the bumper / damper in the back between the main body and the rear triangle. I got the firm block and I am happy with the way it rides, I am 190cm and 82kg so it is under a heavy load but still feels firm and sporty, not at all wobbly. What I don't like / don't understand is the little play between the frame and the rear triangle even when in the locked position. If I lift the bike by the seat, there's a little play and the body moves first - a small gap is formed between the frame and the damper and then the back moves as well. It is perhaps only 5mm but still annoying, if i forget about it and just want to move the bike a little, it makes this clicking sound. I took two photos, first with the bike firm on the flat and the second with me lifting it, you can see there the gap. Is this normal?

Flat on the ground:




Lifted and showing gap:




Thanks a lot,
Ben


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## ukoldschool (23 Oct 2018)

Hi Ben,

I bought my S6 a few months ago and have experienced exactly the same 2 'issues' so you are not alone 

For the quick release clamp, yes its plastic, but its a thick, quality plastic IMO so i'm not bothered about changing it, but mine did start to slip a bit.. I just tightened the nut up a qtr turn at a time until i hit the sweet spot between easy locking and tight post (its easy to tighten it too far so that its hard to close)

I also have the 'play' in the suspension block mechanism, and have thought a fair bit about reducing this but have come to the conclusion that there really is no need. Its there only when no weight is on the bike, and you cant feel it when riding, its also not unsafe as the mechanism is clearly 'locked' into place, so I've stopped worrying about it


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## rogerzilla (23 Oct 2018)

The efficacy of the clamp varies depending on how well the factory reamed the seat tube sleeve, or if they even bothered. The sleeves are also sensitive to how much glue is used - too much in between the sleeve and the seat tube, and they are effectively smaller. Take the bike back to the dealer and ask them to sort it out. Officially only the factory can ream seat sleeves but it's not rocket science. A new sleeve fitted to a well-cleaned out frame with an appropriate amount of glue often doesn't need reaming anyway. I did my own and the action of the QR is perfect. This is the part I'm talking about: https://brilliantbikes.co.uk/brompton-handlebars-and-seat-posts/503-brompton-seat-pillar-sleve.html

Your bike has the latch to prevent the rear triangle hanging down when the bike is picked up. It has no function when riding - don't worry about the gap. I remove the latch completely - earlier Bromptons are free to swing anyway.


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## Pale Rider (23 Oct 2018)

I fell off my Brompton with the latch open.

The bike ended up in the parked position, upright, resting on the carrier.

I was starfished on the road and recall looking up at my bike and a confused passer-by who had stopped to help.

He thought the bike had snapped in two.


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## bence8810 (24 Oct 2018)

Hi all,

Thanks for the replies, I understand the back part has a little play and I won't worry about it since it sounds like it is normal. Indeed no issues with it what so ever when riding, I just didn't like the clinging sound it makes when picked up. Interesting to know that old ones didn't even have that latch holding the back in the locked position...

About the QR, I will keep looking and will also try to investigate which dealer sold the bike, I bought it 2nd hand. 

Currently, I have the nut very tight so even with the QR open, I can't push the seat post back, yet with QR closed the post is still slipping under my weight. Perhaps it's time to go on diet . I'll clean the post first with alcohol and let it dry, clean the sleeve and see if that helps in any way. 

If I don't manage to locate the dealer and I still have the problem, I might just go for a 2nd QR on the post and be done with it.

About the QR clamp, I am still worried about it despite non of you mentioning this as an issue. 






Is this normal that the plastic slips on the nut? When I am tightening it down, the plastic keeps moving but the nut no longer turns. This isn't under extreme force or anything. 

Thanks,
Ben


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## FolderBeholder (24 Oct 2018)

My 3 month old S6L also has seatpost “creep” but my wife’s does not. I am about 215# so I put the hurt on it.
She weighs significantly less!

I have been unweighting my saddle over bumps, transitions, and drainage shallows etc., which has minimized that. 

I wish to avoid adjusting the QR bolt as there are plenty of horror stories of people over-doing that and damaging the seat post and the seat-tube (ovalizing it). I’m an over-doer! So before the warranty period is expired I’ll ask for an adjustment, but at the end of the day unweighting the seat over rough surfaces has all but eliminated it for me.

The suspension block “play” as you call it (I call it a rattle) is typical of both of our household’s Brompton’s and I consider it normal by design fwiw. 

Enjoy your Brompton...I sure am enjoying mine.


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## lazyfatgit (24 Oct 2018)

As posted upthread, get your dealer to sort out the seatpost clamp. I'm 96kg and mine has never slipped.

The clip on the rear is just to make it convenient to lift the bike. I rarely have mine locked as if I'm not riding it I'll either flip the rear under so it's self standing while doing something off the bike or it's being folded.


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## bence8810 (24 Oct 2018)

Thank you all for the answers.

I have now removed the seatpost, cleaned it as well as the tube with the insert where the post goes through.
I've also removed the clamping mechanism and cleaned it, checked and tried to understand it. 

After putting it all back together, - drumroll - nothing changed, same problem.
However, I now noticed that turning the clamp backwards all the way actually works a lot better and totally tightens the setup without any slipping etc. 
Is my clamp put together wrong? I didn't find a way to take it apart. I wish I could somehow turn it around, all my problems would go away immediately!

Any ideas?

Thanks,
Ben


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## CaptainWheezy (24 Oct 2018)

I had exactly the same problem on my wife's S6L. The seatpost clamp moulding doesn't fit tight enough around the nut, and when you tighten it a bit too much, the nut slips its original position and then doesn't apply enough clamping force to secure the seatpost afterwards.

You can see the problem if you look carefully at the photo you posted with the red line drawn around the nut. In your photo, on the bottom inside edge of the plastic that surrounds the hex nut, there is a little notch that protrudes towards the nut. This should be lining up with a notch that is cut into the nut, however on your clamp you can see the nut has slipped / rotated and the notch is now at the 1 o clock position.

I managed to get the nut back into its original position on my wifes bike, and tried all sorts of things (shims in the gap between the nut & plastic, epoxy resin etc), but nothing would fix it / prevent it rotating when tightening the clamp. I ended up having to buy a new clamp. Not expensive but also not impressed considering the bike had only done about 100 miles.

If your bike is still under warranty, get that part replaced.


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## rogerzilla (24 Oct 2018)

Bromptons are the smallest folder and parts availability is better than for other makes, but I'd never pretend they are particularly well made or good value. It's a £200 bike sold for £1000.


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## ukoldschool (24 Oct 2018)

what a load of bollocks /\/\/\


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## rogerzilla (24 Oct 2018)

I've owned three over the last ten years and still have a S3E-X. The components are cheesy, the frame is hi-tensile steel and the price has doubled, without justification, mainly because Cyclescheme facilitates it. But thank you for your insightful contribution.


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## ukoldschool (24 Oct 2018)

ok, could you please:

Explain then how they could be better made?
Show me a brand new British made £200 folding bike.......

You cannot justify whether something is good value as the concept of 'value' and how it relates to you is completely different to how it relates to me and to everyone else, therefore a pointless statement. As is the statement that the components are somehow 'cheesy'? like a bag of wotsits??

I would also love to hear why you believe that the frames should be made of something other than hi-tensil steel (the most commonly used material for bicycles to be made from across the globe), perhaps your engineering and/or road safety qualifications can assist with this? Perhaps your insight can outline the many benefits of why a company successfully making a product out of one material should change the way it does it to suit your wishes?


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## bence8810 (24 Oct 2018)

CaptainWheezy said:


> You can see the problem if you look carefully at the photo you posted with the red line drawn around the nut. In your photo, on the bottom inside edge of the plastic that surrounds the hex nut, there is a little notch that protrudes towards the nut. This should be lining up with a notch that is cut into the nut, however on your clamp you can see the nut has slipped / rotated and the notch is now at the 1 o clock position.



This is it, right on the money!
I managed also to turn the nut back to its place and now the clamp really is working but like you said, it won’t last for me either. It’s already made half a turn and if it does another half, it will lose its grip again. 

I’ll just buy another clamp. What a shame indeed, poorly designed part I think. 

I don’t know who the dealer is or if I had warranty, I got it second hand. I already emailed brompton to try and find out who sold the bike, I will then enquire there. 

Thanks a lot, this really nailed it!
Ben


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## ukoldschool (24 Oct 2018)

I dont think the part is poorly designed, it looks like its been overstressed by poor maintanance?


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## chriscross1966 (24 Oct 2018)

That looks like a clamp that has been overtightened I'm afraid. There are some aftermarket clamps that are stronger (and a lot that aren't, but are pretty).


In response to the person claiming the Brompton is a 200 quid bike, it's made by hand (including a lot of the actual frame welding) from a pile of almost entirely proprietary parts (which it needs to achieve the tiny fold) in a part of London where you could spend 200 quid on lunch and still be hungry to tolerances that have demonstrated that it's the quality of manufacture and not the overall design that counts whenever someone has tried to copy it in the last decade (since the patents ran out).... I'm mildly amazed they can do it as cheaply as they do.


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## FolderBeholder (24 Oct 2018)

Surely there are more of that same qr part correctly doing its intended job, than not. That tells me it’s design isnt flawed, nor is its execution. Could it be improved? Perhaps.

This product is more than the sum total of its (many) parts. Therein lies its value and it’s commanded price and those willing to pay it.

We are buying an entire Brompton...comprised of it’s many parts. Some of those will wear out, some will fail, some may not be perfect. Show me any machine thats any different. 

I like funky machines, warts and all. The Brompton is indeed a funky machine.


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## CaptainWheezy (24 Oct 2018)

ukoldschool said:


> I dont think the part is poorly designed, it looks like its been overstressed by poor maintanance?



I disagree here. This is a cheap part that when it fails, lets the whole bike down (makes it unusable). Like I said, this part failed on my wifes bike, it had done less than 100 miles and had NOT been over tightened. The part is just plain poor design. There is too much slop around the nut to hold it securely, and once it does slip, its game over.

For what its worth, we have 3 Bromptons, all were bought new as S6L's. All have been of variable quality. I'm not saying its a £200 bike, but for the premium asked, there are certainly areas that could be improved, and quality checks seem somewhat lacking.


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## TheDoctor (24 Oct 2018)

The seat QR on my M6R has never needed tweaking in over a decade, and the only bits I've replaced are consumables - tyres, chain and sprockets.
It's not cheap, but it's the only bike I've got that I can take on Eurostar and then tour on it.
Planning on taking it to NZ next year *glees*


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## chriscross1966 (24 Oct 2018)

Ive gone back to the stock clamp on my daily rider, an 11-speed that is a riot of titanium and carbon aftermarket parts.. ive tried several aftermarket ones and not found one as good.


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## bence8810 (25 Oct 2018)

Maybe I was just unlucky then, will go to a brompton dealer here in Tokyo and get the part looked at and try my luck. This bike is nearly unused, totally spotless. I can’t imagine any abuse that might have caused that part to fail. 

I think the brompton is brilliant and I don’t regret the large amount of money I spent on it. There isn’t a bike that’s this versatile out there as far as I know. 

Having said that on my cheapo Dahon Metro 2010, the QR is much better. 

Thanks again for all the help, I’ve just ridden the bike to my station here in western Tokyo (Mitaka) and parked it at my usual underground bike parking spot. The small wheels meant I couldn’t store it in the designated bike racks as the chain tensioner got caught in the guard rails. 
No problem, folded the rear wheel under and parked like a boss at a corner that’s not utilized, the staff at the place was floored! Fantastic bike. 

Thanks for all the help again!
Ben


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## FolderBeholder (25 Oct 2018)

bence8810 said:


> Having said that on my cheapo Dahon Metro 2010, the QR is much better



Maybe the previous owner accidentally tried to ham-fist that QR in the wrong direction and caused that problem, who knows? But a new one....via warrantee or otherwise would likley put this whole issue to bed.

The QR/seatpost on MY $300 EuroMini folder hasn’t ever budged in quite regular use either. And I DON’T unweight the seat on that bike like I do on my S6L. 

BUT...it doesnt fold as well, hold some type of decent resale value, or....did I mention it doesnt fold as well?


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## bence8810 (26 Oct 2018)

So to bring this to an end, I took the bike to a local Brompton distributor who changed the clamp for me (albeit me needing to pay for it) and it works like a charm. There's no gap between the plastic housing and the nut and I haven't yet noticed the post slipping but I'll monitor that further. Most important is the clamp works and this new one indeed looks firm and is fit for purpose. I judged the quality based on the failed part, the new one looks good so far. 

While there I also bought an extended seat post which is much better for my height and the dealer quickly replaced the bottom bracket for free as my serial was in that pool that qualified. 

The dealer also inflated my tire saying it was too low, it is hard as stone now, put 100PSI in. I read that is the factory default, is that really necessary? The bike sure rides faster now but it gives an incredibly bumpy ride.

Thanks all for bearing with me with this issue, glad it is all sorted now!
Ben


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## rogerzilla (26 Oct 2018)

Generally you want to run high tyre pressures, yes, especially at the rear which takes more weight and has suspension to remove harshness. Check the tyre sidewall as 100psi is too high for some 16" tyres and you could blow it off the rim.


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## FolderBeholder (26 Oct 2018)

bence8810 said:


> So to bring this to an end, I took the bike to a local Brompton distributor who changed the clamp for me (albeit me needing to pay for it) and it works like a charm. There's no gap between the plastic housing and the nut and I haven't yet noticed the post slipping but I'll monitor that further. Most important is the clamp works and this new one indeed looks firm and is fit for purpose. I judged the quality based on the failed part, the new one looks good so far.
> 
> While there I also bought an extended seat post which is much better for my height and the dealer quickly replaced the bottom bracket for free as my serial was in that pool that qualified.
> 
> ...


All’s well that ends well.
Thanks for the update.


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## bence8810 (27 Oct 2018)

rogerzilla said:


> Generally you want to run high tyre pressures, yes, especially at the rear which takes more weight and has suspension to remove harshness. Check the tyre sidewall as 100psi is too high for some 16" tyres and you could blow it off the rim.



I checked the tire - it’s the stock brompton - and it says on the tire itself to inflate to 100PSI! I could never do that with the little hand pump. 

I have the firm suspension and with this high pressure, the brompton gives a very bumpy ride but it’s sure enjoyable. 

I hear a lot of road noise, is that normal for the brompton tires? Specially since it’s been inflated according to the specs. 

Another thing I noticed that the whole drivetrain in general is very noisy when comparing it to my old Dahon. Is that normal?

Thanks
Ben


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## TheDoctor (27 Oct 2018)

You'll want a track pump to get up to 100 psi in a reasonable timescale. The small pump that comes with Bromptons really is a get-you-home item at best.
Can't say I've noticed the drivetrain on my M6R being all that noisy - there's a ticking noise from the rear hub gear, but you won't have that.
Is the chain lubed?


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## rogerzilla (27 Oct 2018)

A track pump is a life-changing purchase.

The little pump, as mini-pumps go, is ok but not much fun to use. Kimble did some experiments to prove a 16g CO2 canister wouldn't blow any currently available* Brompton-fit tyre off the rim, so that's an option for roadside repairs.

*the old 28mm Stelvios would probably not cope


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## 12boy (27 Oct 2018)

There are several things that can cause noise ...you haven't said what your drivetrain is. If you have a 3 speed hub, they do make a bit of noise. I put a few ccs of 5-20 synthetic oil in mine whenever it gets noisy, and although it slowly oozes out it is much quieter. When it isn't I put another few ccs in. The polymer suspension block needs to be greased if it is the noise maker. I've noticed it compresses more with a vigorous push on the pedals than it does on a bumpy road. Hold the bike so it can't go forward and press hard on the pedal to see if it is creaking.The seat post will creak if it isn't tight, but only tighten it to the point it doesn't slide down. Too much can ovalize the post. I prefer leather saddles and they too can creak a bit. Finally, the hinge for the rear triangle can also make noise if the bolts are loose, the bushings shot or it isn't oiled where the nylon washers sit on the bike. Hopefully you keep your chain well lubed as a dry chain isn't quiet. I have in the past had trouble figuring out where noise is coming from, since it seems to travel up the seat post. BTW, I only put about 75 PSI in my tires as whatever speed I've lost is made up for by comfort.


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## TheDoctor (27 Oct 2018)

12boy said:


> There are several things that can cause noise ...you haven't said what your drivetrain is. If you have a 3 speed hub, they do make a bit of noise. I put a few ccs of 5-20 synthetic oil in mine whenever it gets noisy, and although it slowly oozes out it is much quieter. When it isn't I put another few ccs in. The polymer suspension block needs to be greased if it is the noise maker. I've noticed it compresses more with a vigorous push on the pedals than it does on a bumpy road. Hold the bike so it can't go forward and press hard on the pedal to see if it is creaking.The seat post will creak if it isn't tight, but only tighten it to the point it doesn't slide down. Too much can ovalize the post. I prefer leather saddles and they too can creak a bit. Finally, the hinge for the rear triangle can also make noise if the bolts are loose, the bushings shot or it isn't oiled where the nylon washers sit on the bike. Hopefully you keep your chain well lubed as a dry chain isn't quiet. I have in the past had trouble figuring out where noise is coming from, since it seems to travel up the seat post. BTW, I only put about 75 PSI in my tires as whatever speed I've lost is made up for by comfort.


The OP has an M2R - that's a 2 speed cassette and no hub gear.
Good call on the chain though - I was out earlier and someone cycled past with a chain that sounded like a very upset hamster.


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## Joe Brom (27 Oct 2018)

The moral of this story is a qr you know to have been used by a previous owner may not have been used correctly. You'd be amazed how often this happens on seat clamps *and* wheels. Good on ya for getting a new one only *you *have fiddled with.


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## bence8810 (31 Oct 2018)

Almost a week into the clamp upgrade, wanted to post back.

The seatpost is slipping but nothing major. A little annoying but I see this happens to a lot of users. I am a big guy and also ride semi-hard so I can't really complain - I try to de-weight the seat on bumps etc and like this its manageable. I also think (hope I am not dreaming) that it is getting better a little every day, perhaps the new seat post I had just installed had some oil / residue on it.

The drivetrain noise is not a problem, I watched many videos online and all bromptons are like this. My Dahon was a lot quieter, I guess it is just the different components being used. The Brompton is definitely of the better of the two systems, there is a lot less rolling resistance from what I can see.

Very happy with the bike, have put in about 100km's over the weekend and all is working well!

Thanks again,
Ben


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## 12boy (31 Oct 2018)

If you read this forum you have encountered an easy fix for seat slippage... a 31.8 seat QR with the lip filed off used on the seat post just above the seat tube. It will definitely keep the post from sliding down. Just release it too when folding the bike. The other cheap and easy thing is to use the seat post limiter that you cut so as to only allow the seat to up as much as you need. If you are frequently having to readjust for slippage this will make that a lot easier.


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## bence8810 (1 Nov 2018)

12boy said:


> If you read this forum you have encountered an easy fix for seat slippage... a 31.8 seat QR with the lip filed off used on the seat post just above the seat tube.



Yes - I have that QR thing added to my cart on a major e-retailer's site but really don't like the idea of having two clamps. I will see for a bit more if it improves on its own, I do believe in miracles. If not, I'll perhaps go for an extra QR.

Thanks,
Ben


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## Banjo (23 Nov 2018)

My seat post slipped a bit when new but after 6 months of regular use doesn't slip now.


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## steveindenmark (25 Nov 2018)

12boy said:


> If you read this forum you have encountered an easy fix for seat slippage... a 31.8 seat QR with the lip filed off used on the seat post just above the seat tube. It will definitely keep the post from sliding down. Just release it too when folding the bike. The other cheap and easy thing is to use the seat post limiter that you cut so as to only allow the seat to up as much as you need. If you are frequently having to readjust for slippage this will make that a lot easier.



I spoke to Brompton Junction in Hamburg and they didnt rate the seat post limiter at all.


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## Kell (28 Nov 2018)

steveindenmark said:


> I spoke to Brompton Junction in Hamburg and they didnt rate the seat post limiter at all.



I think it's really useful. 

Takes a bit of fettling to get it exactly right, but now I pull the seatpost as far up as it will go and just make sure the seat's pointing forwards. I can't see how anyone would think it wasn't a good addition...

(The only exception to this is when I hired a Brompton with an extending post. I pulled the bottom bit out to the full length, then set the top bit to the correct height. Then all I ever needed to do was leave the top bit clamped in place and pull the bottom bit right up.)


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## Nibor (28 Nov 2018)

I am luck in that my seat post appears to be exactly the right length for me without the limiter.


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## TheDoctor (1 Dec 2018)

The Pentaclip has some adjustment, including moving the saddle rails between top and bottom clamps. Playing with this can get your saddle so that raising the seatpost fully makes the length just right 
And it's always worth degreasing the seatpost as a first move.


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