Cam MTB - the Cambridge Mountain Bikers' Forum

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DISCLAIMER. MOUNTAIN BIKING CAN BE DANGEROUS. YOU JOIN US AT YOUR OWN RISK.

SAFETY BRIEFING.

  • Wear a helmet. Despite recent advances in medical science, brains still cannot be mended nor replaced.
  • Wear gloves or mitts. Hands often hit the ground first. Cuts and grazes invite infection and a hospital visit.
  • Wear eye protection, it only takes a twig or thorn to lose an eye. Crud catchers are a good idea in mucky weather.
  • When downhilling, for your own protection, allow plenty of space behind the rider in front.
  • Bring a bare minimum emergency tool kit and a spare inner tube.
  • Breakdowns are a bore. Plan not to have any by ensuring your bike is in perfect working order.
  • Punctures are also tedious. You can minimise them by fitting latex tubes, slime tubes or running tubeless tyres.

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Dropping Seatposts - paging Pat

Looking at getting a dropping Seatpost for the Zesty. Choice seems to have boiled down to infinite hydraulic type, or cable operated 3 position type. Understand Pat has done a fair bit of research on these so glad of any advice.
Thanks

Re: Dropping Seatposts - paging Pat

Rock Shox Reverb

Re: Dropping Seatposts - paging Pat

I have a reverb. Ask Dom, he's got a different one (KS Lev) and I expect he did days of tedious research and will tell you all about it.

Re: Dropping Seatposts - paging Pat

I have the Rockshock Reverb too.
Awesome piece of kit and it has improved my confidence on the bike so much.

There are varying size of post option, as you would expect.
Two different height options 4 inch and 5 inch, and a choice of internal frame routing or external, and left or right remote leaver.

It is important to measure your seat rails to seat clamp, then add about 18mm to the drop height to allow for the base of the post to protrude out of the frame.
Ok I went for the biggest drop height and to be honest this was a mistake, I only needed the shorter one. It is 5mm too tall
I do not have long enough legs with this bike frame to accommodate all of the height, and there is no way to limit how heigh it returns to (full extension or ages searching for the right point) but there is a clamp to limit how low it drops, being an engineering kind of person I suspect you could come up with something creative if need be. I have also limited how low it drops as the 5inch drop is too much for Cambridge.
As for the routing of the pipe, it is ugly on the outside and flaps around when the seat is down, and I suspect long term it will be susceptible to wear and tear.......but it is either that or drill a hole in the frame to accommodate the pipe. I went for the external.

One thing to note is that there is a small amount of play in the bushing on the post, this gives a couple on mm play in rotation as well as rock back and forwards as well as side to side. I do not notice it while riding but for some people it is a real turn off.

The reason I chose this kind of post is because it had got 10/10 for 3 consecutive tests in MBR, so it can't be bad, also it is so easy to adjust your seat height on the move, you don't need to stop to sort it out.

This helps on descents, but also single track and when you stop at the traffic lights.

I believe Dom did buy a KS Lev with a leaver under the seat, but I also believe he has put that on Alison's bike, and gone down the reverb route himself now. Correct me if I'm wrong Dom.

Last thing to say about the Reverb, the handle bar leaver is very fragile and £110 to replace if damaged. This can be done while fixing a puncture or in a crash. Comments on the web suggest you buy the leaver version of the other side to where you want to mount it, and then put it under the bars for protection. I.e. If you want it on the right buy a left hand option an then flip it upside down on to the right.

Hope this helps you decide.

I have been using mine for about 18 months now and it still works fine......just keep it clean, use a mud guard.

Pat

Re: Dropping Seatposts - paging Pat

Hi Pat,

Thanks very much for exactly the info I was after.

I'm tempted to go for the internal hose/pipe version. But will keep studying the market as I think a cable operated one would be lighter, and easier to fix, and still do what I need it to do!

Thanks

Pete

Re: Dropping Seatposts - paging Pat

Pat,

Are you pitching for this years most geeky post of the year award? I thought that I would never see Dom's thesis on sock and shoe selection ever being beaten in my lifetime but hats of to you - I think you have come pretty damn close!

Inviting Dom to contribute to your post is a true master stroke as he will surely weigh-in with additional facts pertaining to drop seat posts which will delight the insomniacs amongst us and strengthen your claim to Geeky post of the year.

My money is still on Dom to have a late solo attempt on some obscure cycling topic that no one is interested in (unless you find socks interesting in which case you should stay at home surfing sock porn rather than riding a bike)

Personally, I'm gunning for the most sarcastic rider of the year but realise I have stiff competition from Mark T.

Re: Dropping Seatposts - paging Pat

LMFAO!!!
Mike, you must be up for best comeback of the year with your "mistaken identity"post.
Master stroke.

Re: Dropping Seatposts - paging Pat

Hi Pete

Alison and I have both got KS Supernaturals. I've got one with a remote and Alison has one with an under-saddle lever, which I don't think they do anymore, although you can get them on eBay. The latest one has a different (and I assume better) cable to seatclamp assembly than mine. In terms of Pat's comment about keeping it clean, it's that bit on mine that needs attention - I've made a DIY cover out of a bit of old inner tube that looks terrible but seems to do the trick.

Pat's right about making quite sure you get the right length. If you get one that's too long for you and/or your bike, the fully extended position will be higher than you can or want to ride. Part of the attraction of the post is that when you raise it after riding with it down, it goes back to exactly the right position every time, and you don't want to lose that functionality. I know that included in the price of a service, TF Tuned will adjust the travel on a Reverb to give you a reduced maximum height. I don't know if they do it for any other post.

I got my KS because, to be blunt, it was cheap! I couldn't bring myself to spend 300 quid on a Reverb - which is what they were at the time. The Supernatural was a lot cheaper than the Reverb anyway, and I got a good deal because the UK importer had recently stopped bringing them in or supporting them, so it was a bit of a gamble. (There is now an importer again.) It was also cheap because I got one with an under-saddle lever rather than a remote.

We then got Alison one with a remote (bought in the US and even cheaper - spot a theme?), but she found the remote lever stiff for small hands, so we swapped. I wouldn't now go back to a post without a remote, but on the other hand Alison really likes her set-up - the lever under the saddle has a very smooth action and takes very little force to activate.

Hydraulic vs spring internals?
- Weight is not really an issue. This comparative review is recent and seems quite comprehensive and well written. Comments suggest that it should have included the Gravity Dropper. That one does appear to be a bit lighter than most.
- Maintenance and reliability - if the hydraulics fail, you'd have a post stuck in the down position, which wouldn't be the case with a spring. I wonder how often that actually happens? I don't think I've ever seen any mention of it on forums.

Hydraulic vs cable remote?
- I've no idea. Cable a few grammes lighter? Mine is cable and I can take it off and clean it and it would be much cheaper if I had to replace it. On the other hand, you don't need to clean a hydraulic cable, and I can't see that they're likely to fail much.

Infinite vs 3-position
- I really really like the infinite adjustability. I'm still amazed a year on at how much I adjust it, how often, and at the difference a couple of cms can make, vs five cms, vs ten cms, vs the whole travel... Also, from what I read (no personal experience) the 3-position posts can be hard to 'find' the middle position. For me, this is really important. If you're mucking around trying to get it into the right position or to lock in place, you might as well get off and use a seatpost clamp. The whole point is being to make really quick changes on the fly - get to a gnarly bit and drop the post - bam!

Saddle clamp layback
- Watch out for inline vs layback. For me, a layback clamp would put the saddle too far back on the bike.

Travel
- I've got 125mm, which is about right for me - I do use the full travel sometimes in the Peaks or Wales. 100mm would still be good, 75mm wouldn't be enough for me. Alison's is 75mm because that's all she could have with her frame that would allow the right highest position (see above). She finds that, because she's shorter and on a smaller bike, 75mm is enough.
- It depends where you're planning on using it and what for. Although I do use it round Cambridge, if I didn't have it I can't honestly say I'd miss it. For me, it's all about 'technical' terrain, particularly going down - so Peaks, Wales, Lakes, Cannock...

Play
- Mine has the same sort of play as Pat mentions. Minimal, and I absolutely don't notice it when I'm riding. I do when I pick the bike up by the saddle, and it annoys me! :-)

Lever
- I've heard the same as Pat says about Reverb lever position on the bars and vulnerability. The KS lever is small and protrudes very little. I can't see it getting bust in a crash (famous last words!). I've read that the Fox lever is enormous and vulnerable as well.

Hope that helps! And that I've written enough to live up to my reputation. I'm not sure I got enough hyperlinks in there...
Dom

Re: Dropping Seatposts - paging Pat

Absolutely brilliant, thanks very much Dom. Its now just down to dimensional analysis before specifying the Reverb. And the good news is that it looks like Pat could get his maximum height reduced for the price of a service

But I did think you could have got an FMEA in there. However, I remain convinced this thread will win TGOTYA.