Wisper 705SE seatpost

[ruy lopez]

Mrs Lopez has got a 705SE, but the saddle doesn't come up high enough for me. If I could get a seatpost of say 500 mm (the existing one is 350 mm) then I could do a quick saddle swop if I fancied a go on it while she was not looking.

I've measured the diameter as 27 mm, although seatposts in general seem to be specified as 27.2 mm. But I can't find any 500 mm seatposts for sale on the Internet anyway, either at 27 mm or 27.2 mm diam. Do such seatposts exist anywhere? I wouldn't need the tilting sort, just standard.

 

[Mussels]

I'm interested to know what you find as I find the seat post a little short and I have it over the max line. I thought about one of the Thudbuster posts until I saw the price!

 

[Danny-K]

... I've measured the diameter as 27 mm, although seatposts in general seem to be specified as 27.2 mm. But I can't find any 500 mm seatposts for sale on the Internet anyway, either at 27 mm or 27.2 mm diam. Do such seatposts exist anywhere? I wouldn't need the tilting sort, just standard.

The seatpost almost certainly will have the diameter stamped on the post, (usually below the minimum insertion markings), as I doubt you'd get an accurate reading between 27.0 and 27.2 by eye alone, (micrometer needed) - no, instead look for the stamped measurement - it should be there.

Also, I doubt very much whether you are going to get a seatpost longer than 400mm anywhere. And remember although it's 400mm in length, measuring from the minimum insertion point, to a point midway between the saddle rails is going to be considerably less than 400mm, (about 100mm less), due to the length of post required for grip and safety reasons be below the minimum insertion point that must be inside the seat tube and therefore, to all intents and purposes being the 'unusable' portion of the seat-post.

An LT Extra Long Thudbuster is longest at 450mm in total I believe - but you'd be paying well over a hundred pounds - got my 400mm seatpost, (ETC brand), off eBay for £12.49 all-in delivered. Beautifully light it is too.

Loads on eBay so 400mm should be readily available quite inexpensively from your local bike shop - it'll be much longer than the stock item you have at present, that's for definite.

Raleigh 400mm seat-post for comparison -

 

[ruy lopez]

Well, here's an idea. But it means you have to use a unicycle saddle, I assume.


Nimbus Steel Seat Post (25.4mm)

£5.00

25.4mm diameter standard seat post. Four bolt fittings to fit Nimbus, Viscount, Dodger, Trainer, Kris Holm, Velo and the majority of unicycle seats.

Six lengths available - 220 mm to 700 mm.

Unicycle.UK.com - Product Page - "Nimbus Steel Seat Post (25.4mm)"


Seatpost adjustable shim for 25.4mm post.

£3.99

This seatpost shim is designed to accept a 25.4mm seatpost and the adjustment ranges from 26.4mm to 28.0mm diameter frames tubes.

Raleigh Seatpost adjustable shim for 25.4mm post.

 

[ruy lopez]

Hi Danny-K. Just seen your post. Yes, you are right. Thanks. I looked on the seatpost and it does indeed say 27.2 mm. So I know that a seatpost specified as 27.2 will do. However, the actual diameter is 27 mm measured with a micrometer and with a vernier caliper - well 27.05 anyway.

I know about the usable length, etc. What I did was put the saddle in at the max safe height and measure saddle to pedal, which was about 36 inches. Then I measured saddle to pedal on my Ridgeback, set up how I like it, and that's about 40 inches. So I need another 100 mm of seatpost. Since the current Wisper one is 350, I could manage with 450. Of course 500 would be better, so I wouldn't have to put it at the max setting.

 

[Mussels]

I found increasing the seat post preload helped as the seat wasn't at the bottom of it's travel all the time. Although it won't help Ruy if anyone else wants to try then use a 5mm hex key (Allen key) from the underneath, the large nut on the outside just holds it all together.

 

[ruy lopez]

I see that for under a tenner I could get an long seatpost of the unicycle variety - up to 700 mm.

Unicycle.UK.com - Product Page - "Nimbus Steel Seat Post (25.4mm)"

That's 25.4 mm diam, but a shim would take it up to the required 27.2 mm. Questions are:

Can you put a normal saddle on it?

Can you feasibly ride a bike with a unicycle saddle/seat?

 

[ruy lopez]

I tried to edit that last post to acknowledge the fact that I'd said much the same thing earlier. I was getting confused by posting a similar thing on another message board.

But my edit didn't appear (not yet anyway). I expect it will appear now I've posted this.